Confused about redshift and age of stars
Jan Panteltje
and did assume a big bang, and the redshift caused only by Doppler,
then the most redshifted stars would be the furthest away, but just
as old as our sun?
This is why I think that:
Origin of BB:
O
After some years, A and B are stars speeding away from the BB origin:
A O B
After even more years:
A O B
Now suppose we are on star B, then for us star A will move faster away
then any star in position O, so star A will be more redshifted.
So when we look at the most redshifted stars, we merely look at the ones
that are speeding away at the highest speeds, and that are those on
the 'opposite' (sorry 2D picture) of the BB origin.
But they often say: 'this (the most redshifted) is the oldest......'
So where am I wrong?
Scott Miller
Assuming you are looking past the origin of the universe (there isn't
such a data point) to a star farther away. Unless you understand the
actual model of the universe, you will remain confused.
At an earlier epoch, all galaxies were closer than they are now. Stars
born at that time begin to live out their lives and shine into the
universe. In the time that it takes the light to reach us, the universe
has continued to expand. The light is redshifted because of that
expansion and the light we detect is also from that earlier epoch, not
from the current one. So, we are seeing the stars as they were at that
earlier epoch, not as they are now.
The stars shine continously over this time and the light they emit
becomes even more redshifted by the expanding space-time. It now has to
travel an even greater distance to reach us, which means we are still
seeing those stars as they were at earlier epochs, not as they are today.
The end result of all this is that those stars that are farthest from us
as determined by their large redshift (galaxies rather than individual
stars, for the picky!!) have had their light traveling the farthest
amount of time to reach us, being redshifted along the way and revealing
us as they were, not as they are.
Note that in this explanation that we may be the center of observation
but located randomly within the universe, so that the same observation
would be made no matter where one was in the universe. There need be no
center of expansion, just an apparent expansion from the point of
observation.
OG
"Jan Panteltje" <pNaonSt...@yahoo.com> wrote in message
news:e3pkp1$4ma$1...@news.datemas.de...
Think of the image of the stars as photos taken out of a family album. When
looking at local galaxy (no redshift) stars, we can think of these as
recently taken images of your children. Images of Andromeda galaxy are
photos of your children as babies, Virgo group galaxy images are your own
wedding photos, Coma cluster galaxies are you as a child. As we look at
further distances we see images of your parents' wedding day, and further
back, your parents as children, your grandparents in their prime, your
grandparents as children and maybe even your great grandparents.
A picture of your great grandparent as a child will be older than a picture
of the same great grandparent's wedding day - which is why they talk as they
do.
By the way, the "A O B" view of the expanding universe is misleading,
because as the universe expanded the O also expanded and the A and the B
remained inside it! This is irrelevant to the main point of your question,
but it is something that you will appreciate as you read more about the
expansion of the universe.
Thomas Smid
the universe but with the finite speed of light. Whether or not an
object is moving relatively to you, you will always see it as it was a
time t=d/c ago (where d is the distance of the object and c the speed
of light). In this sense, you should actually say that an object at a
larger distance shows it at a *younger* stage, not an older (if you
look at a photo of somebody, then it will always show the individual at
an age younger than its present age).
Having said this, it is in my opinion actually more than questionable
that the redshift of galaxies is related to an expansion of the
universe (see my webpage
http://www.plasmaphysics.org.uk/research/redshift.htm ).
Thomas
Igor
Space is isotropic and YOU are at O.
Jan Panteltje
<jsfm...@netzero.net> wrote in <e3r3kn$116r$1...@news.louisville.edu>:
>The end result of all this is that those stars that are farthest from us
>as determined by their large redshift (galaxies rather than individual
>stars, for the picky!!) have had their light traveling the farthest
>amount of time to reach us, being redshifted along the way and revealing
>us as they were, not as they are.
>
>Note that in this explanation that we may be the center of observation
>but located randomly within the universe, so that the same observation
>would be made no matter where one was in the universe. There need be no
>center of expansion, just an apparent expansion from the point of
>observation.
OK, it is clear to me now.
I want to thank you and the other posters for the replies.
Much appreciated.
Jan Panteltje
<thoma...@gmail.com> wrote in
<1147250816....@v46g2000cwv.googlegroups.com>:
Hi, I have been at you webpage, and if i understood this right,
you say that the electric fields thayt exist around stars cause a
lightbeam to deflect, and that that is the reason for the Einstein Cross, not gravity?
It should not be too difficult to ionize some neon with a few kV or RF energy,
and beam a laser pointer through it.
has this been done?
If so did the ionized gass deflect the light and in what direction?
Or are you saying it is ONLY the electric field that causes this?
Experiments?
That is not mainstream, but why would the beam defelct around and for example not
away, what sort of electric fields (polarity and gradient) do you expect?
Your webpage brings up many many questions....
Thomas Smid
I am suggesting that it is *only* the electric field that causes this.
Otherwise, it would hardly be able to cause a redshift in intergalactic
space as the distance between two particles is larger than the length
of a 'photon'.
With regard to the deflection, which I specifically treated on my page
http://www.plasmaphysics.org.uk/research/lensing.htm : as mentioned
there, the electric field around the sun should have a strength of
about 10^-6 V/m (due to the sun being positively charged at a potential
of about 1 kV) However, it extends over about 10^6 km , so you need
correspondingly higher field strengths for lab dimensions. If you
assume a quadratic dependence (as suggested on my webpage), then you
find that you would need lab field strengths of the order of the
inner-atomic field, which are obviously impossible to create (as it
would tear the whole lab apart at the same time) . The whole effect is
thus very much associated with astronomical distances and it is
therefore not surprising that it is unknown in classical mainstream
physics.
Thomas
Jan Panteltje
<thoma...@gmail.com> wrote in
<1147339359.0...@j33g2000cwa.googlegroups.com>:
>With regard to the deflection, which I specifically treated on my page
>http://www.plasmaphysics.org.uk/research/lensing.htm : as mentioned
>there, the electric field around the sun should have a strength of
>about 10^-6 V/m (due to the sun being positively charged at a potential
>of about 1 kV) However, it extends over about 10^6 km , so you need
>correspondingly higher field strengths for lab dimensions. If you
>assume a quadratic dependence (as suggested on my webpage), then you
>find that you would need lab field strengths of the order of the
>inner-atomic field, which are obviously impossible to create (as it
>would tear the whole lab apart at the same time) . The whole effect is
>thus very much associated with astronomical distances and it is
>therefore not surprising that it is unknown in classical mainstream
>physics.
>
>Thomas
OK, my apologies, I did read it again (but full day of stuff was in between),
and did see you addressed all that.
Now for the question I hope you did not already address:
You know black holes have been detected by these passing in front of 'stars' and
causing us to see the Einstein Cross.
So, if your theory is right, also black holes would beam electrons outward?
Thomas Smid
> Now for the question I hope you did not already address:
> You know black holes have been detected by these passing in front of 'stars' and
> causing us to see the Einstein Cross.
>
> So, if your theory is right, also black holes would beam electrons outward?
A good point, but I don't think that it invalidates my theory.
First of all, 'black holes' in the strict sense as suggested by
Relativity are still very much hypothetical objects that lack
definitive observational proof (see for instance section 5 in
http://www.iop.org/EJ/article/1367-2630/7/1/199/njp5_1_199.html ). Even
if you assume they exist and that thus no electrons can escape from it,
the point is obviously that the object was not always a black hole and
thus electrons would have been able to escape before the black hole
stage was reached, which also would leave the latter positively
charged. Also, plasma surrounding the black hole would lose electrons
by the same mechanism and therefore would also produce an apparent
charging of the black hole.
Thomas
dlzc1 D:cox T:net@nospam.com N:dlzc D:aol T:com (dlzc)
"Thomas Smid" <thoma...@gmail.com> wrote in message
news:1147359658.0...@j73g2000cwa.googlegroups.com...
> Jan Panteltje wrote:
>
>> Now for the question I hope you did not already address:
>> You know black holes have been detected by these
>> passing in front of 'stars' and causing us to see the
>> Einstein Cross.
>>
>> So, if your theory is right, also black holes would beam
>> electrons outward?
>
> A good point, but I don't think that it invalidates my theory.
> First of all, 'black holes' in the strict sense as suggested by
> Relativity are still very much hypothetical objects that lack
> definitive observational proof (see for instance section 5 in
> http://www.iop.org/EJ/article/1367-2630/7/1/199/njp5_1_199.html
> ).
Try something current:
"Dying Star Reveals More Evidence for New Kind of Black Hole
(Forwarded)"
Posted by Andrew Yee here: Friday, January 06, 2006 11:23 AM
... and especially ...
"Scientists Find Black Hole's "Point of No Return" (Forwarded)"
Posted by Andrew Yee here: Monday, January 09, 2006 9:48 AM
David A. Smith
Jan Panteltje
<thoma...@gmail.com> wrote in
<1147359658.0...@j73g2000cwa.googlegroups.com>:
>Jan Panteltje wrote:
>
>> Now for the question I hope you did not already address:
>> You know black holes have been detected by these passing in front of 'stars' and
>> causing us to see the Einstein Cross.
>>
>> So, if your theory is right, also black holes would beam electrons outward?
>
>A good point, but I don't think that it invalidates my theory.
>First of all, 'black holes' in the strict sense as suggested by
>Relativity are still very much hypothetical objects that lack
>definitive observational proof (see for instance section 5 in
>http://www.iop.org/EJ/article/1367-2630/7/1/199/njp5_1_199.html ).
That is a very nice link, took me some hours to work myself through it.
It brings up that they think BHs are mostly electrically neutral, that
does not support your idea.
Also it made me think about 'asymmetry' in the accretion disk,
if your theory is right, the we should perhaps see asymmetry
in the Einstein Cross too, as electron emission form both a BH or NS
would not be the same in all directions (also look at the movies they
have on that site, Movie5.avi, Movie6.avi, showing the forming of jets).
Thomas Smid
> On a sunny day (11 May 2006 08:00:58 -0700) it happened "Thomas Smid"
> <thoma...@gmail.com> wrote in
> <1147359658.0...@j73g2000cwa.googlegroups.com>:
>
> >Jan Panteltje wrote:
> >
> >> Now for the question I hope you did not already address:
> >> You know black holes have been detected by these passing in front of 'stars' and
> >> causing us to see the Einstein Cross.
> >>
> >> So, if your theory is right, also black holes would beam electrons outward?
> >
> >A good point, but I don't think that it invalidates my theory.
> >First of all, 'black holes' in the strict sense as suggested by
> >Relativity are still very much hypothetical objects that lack
> >definitive observational proof (see for instance section 5 in
> >http://www.iop.org/EJ/article/1367-2630/7/1/199/njp5_1_199.html ).
>
> That is a very nice link, took me some hours to work myself through it.
> It brings up that they think BHs are mostly electrically neutral, that
> does not support your idea.
I didn't actually notice that statement, but the argument given there
for neutrality ("an astrophysical BH is not likely to have any
significant electric charge because it will usually be rapidly
neutralized by the surrounding plasma") is in fact incorrect. According
to this argument the phenomenon of 'spacecraft charging' (see
http://www.eas.asu.edu/~holbert/eee460/spc-chrg.html ) should for
instance not exist. The point is that an equilibrium requires the net
*current* to be zero but not the charge. If you have a region of plasma
which in any form has a higher volume density or higher energy than the
surrounding region, then it must be positively charged. If it is not
the black hole itself here, then the accretion region around it. Like
for the spacecraft charging, the charge will have a potential which
corresponds to the average electron energy of the plasma (which is
about 10 V in case of the spacecraft charging, 1 kV for the sun and
about 2*10^8 V for a black hole assuming that the plasma outside the
Schwarzschild radius is in thermal equilibrium, and in virial
equilibrium with gravity).
Thomas
Craig Markwardt
"Thomas Smid" <thoma...@gmail.com> writes:
...
>
> I am suggesting that it is *only* the electric field that causes this.
> Otherwise, it would hardly be able to cause a redshift in intergalactic
> space as the distance between two particles is larger than the length
> of a 'photon'.
> With regard to the deflection, which I specifically treated on my page
> http://www.plasmaphysics.org.uk/research/lensing.htm : as mentioned
> there, the electric field around the sun should have a strength of
> about 10^-6 V/m (due to the sun being positively charged at a potential
> of about 1 kV) However, it extends over about 10^6 km , so you need
> correspondingly higher field strengths for lab dimensions. If you
> assume a quadratic dependence (as suggested on my webpage), then you
> find that you would need lab field strengths of the order of the
> inner-atomic field, which are obviously impossible to create (as it
> would tear the whole lab apart at the same time) . The whole effect is
> thus very much associated with astronomical distances and it is
> therefore not surprising that it is unknown in classical mainstream
> physics.
However, there are very significant problems with non-cosmological
redshifts. As I noted in sci.astro.research article
<mt2.0-2096...@hercules.herts.ac.uk> in reply to Robin Whittle,
: A non cosmological theory of redshifts would have a lot of serious
: problems to address, namely,
:
: * how cepheid variable stars, which have a known period-luminosity
: relationship in the local universe, would have a period-luminosity
: relationship in redshifted galaxies which is exactly tuned to the
: redshift of the galaxy? I.e. how would each cepheid know to tune
: its luminosity to the intrinsic redshift of the galaxy?
:
: * how could the Lyman alpha forest exist? I.e. how could absorption
: systems be seen at multiple intervening redshifts, but not at higher
: redshifts?
:
: http://www.astro.ucla.edu/~wright/Lyman-alpha-forest.html
:
: * if redshift is intrinsic to the host galaxy, how could the *same*
: Lyman alpha absorption system appear in two *different* galaxy
: spectra, which are on nearby lines of sight?
:
: Young, P. A., Impey, C. D., Foltz, C. B. 2001, ApJ, 549, 76
:
: * for Arp-like theories where the redshift is intrinsic to the
: galactic nucleus, how could maser systems exist distinct from the
: nucleus which have the same redshift as the nucleus?
:
: Kondratko, P. T., Greenhill, L. J., Moran, J. M. 2005, ApJ, 618, 618
: Herrnstein, J. R. et al. 1999, Nature, 400, 539
: Yates, J. A. et al 2000, MNRAS, 317, 28
:
: * for non Arp-like theories, where the redshift is created in the
: neighborhood of the galaxy by some gas or plasma, how could the
: redshift "process" -- whatever it is -- physically generate
: indentical redshifts at both microwave and optical wavelengths?
: I.e. all electromagnetic processes I am aware of are highly
: chromatic.
:
: * for that matter, how could any "plasma effect" shift the wavelength
: of emission, without doing other things like line broadening?
: I.e. why aren't high redshift lines also highly broadened?
:
: * why the cosmic microwave background in the high redshift universe
: was apparently hotter?
:
: Molaro, P., et al. 2002, A&A, 381, L64
: Silva, A. I. & Viegas, S. M. 2002 MNRAS, 329, 135
: Srianand, R. Petitjean, P. & Ledoux, C. 2000, Nature, 408, 931
:
: * in NGC 4258, which has maser emissions from a disk of material
: around the nucleus, both radial (Doppler) and transverse (proper
: motion) velocity measurements have been made. These follow exactly
: the profile of a Keplerian disk, but only if the distance is 7.2 +/-
: 0.3 Mpc. This compares well to the cepheid distance to the galaxy,
: assuming the Hubble law.
:
: Caputo, F., Marconi, M., & Musella, I. 2002, ApJ, 566, 833
: Herrnstein, J. R. et al. 1999, Nature, 400, 539
:
...
And to move on to your particular theory, as you freely admit, your
theory is highly wavelength-dependent (dependent on the wavelength of
radiation vs. the intramolecule spacing of the IGM); and yet, all
evidence of spacetime/redshift effects are that they are achromatic.
Examples: solar system Shapiro delay in radio vs. X-ray (personal
knowledge); Shapiro delay in other binary systems (van Straten et al);
bending of optical light by the sun, even at 90 degrees to the Sun
[Hipparcos results] (Froeschle et al); and deflection of light by
Jupiter (Treuhaft & Lowe).
The Jupiter test is perhaps most telling, since Jupiter is not really
hot enough to have a surface plasma, and yet it still deflects light
in proportion to its mass as GR predicts.
Froeschle, M., et al 1997, ESA SP-402: Hipparcos - Venice '97, 402, 49
van Straten et al. Nature, 412, 158 (http://arxiv.org/abs/astro-ph/0108254)
Treuhaft, R. N. & Lowe, S. T. 1991, AJ, 102, 1879
Fundamentally, there is no mechanism by which a static electric field
is known to modify electromagnetic waves; this is a trivial
application of the superposition principle to Maxwell's Equations [*].
You mention casually on one of your web pages some kind of resonance
between the time-varying electric field of the atom and the frequency
of the electromagnetic wave. This is, in a sense, what atomic
lines/transitions are, but these are highly wavelength dependent, and
do not have the effect of shifting the wavelength of radiation
continuously (rather, producing absorption or emission lines).
Considering for the moment, that your theory of deflection of
radiation by electric fields were substantiated (which it's not); and
your claim of the electric potential of the sun being 1 kV were
substantiated (which it is not)... It's worth pointing out that the
static earth potential is over 350 kV, over 350 times your claimed
potential for the sun (ref. Dolazek). And yet, no significant
deflection of light is apparent in the earth system. Indeed, the GPS
system is sensitive at the few millimeter level (i.e. tens of
*micro*arcseconds for the GPS satellite positions), for which such
deflections would have been detectable (Wolf & Petit).
Dolezalek, H. "Atmospheric Electricity" CRC Handbook, 67th Ed., p. F-149.
Wolf, P., & Petit, G. 1997, Phys Rev A, 56, 4405
In short, you came up with some plausibility argument and declared
victory, without doing a rigorous comparison of your argument to the
real observations. Not really convincing.
CM
[*] ignoring for the discussion the quantuum effects at very high
energies where the Klein-Nishina cross section becomes significant
Thomas Smid
I assume you are referring here to an effect similar to the delay of
supernova light curves. I have covered this on my page
http://www.physicsmyths.org.uk/redshift.htm . Basically, in general, if
a 'stretching' of the light wave (by whatever mechanism) leads to a
redshift, this is also likely to be associated with a reduction of the
amplitude of the wave i.e. a reduction in its intensity (additionally
to the usual 1/r^2 decrease). This leads therefore to an
underestimation of the absolute luminosity of the object.
> :
> : * how could the Lyman alpha forest exist? I.e. how could absorption
> : systems be seen at multiple intervening redshifts, but not at higher
> : redshifts?
> :
> : http://www.astro.ucla.edu/~wright/Lyman-alpha-forest.html
> :
> : * if redshift is intrinsic to the host galaxy, how could the *same*
> : Lyman alpha absorption system appear in two *different* galaxy
> : spectra, which are on nearby lines of sight?
> :
> : Young, P. A., Impey, C. D., Foltz, C. B. 2001, ApJ, 549, 76
> :
> : * for Arp-like theories where the redshift is intrinsic to the
> : galactic nucleus, how could maser systems exist distinct from the
> : nucleus which have the same redshift as the nucleus?
> :
> : Kondratko, P. T., Greenhill, L. J., Moran, J. M. 2005, ApJ, 618, 618
> : Herrnstein, J. R. et al. 1999, Nature, 400, 539
> : Yates, J. A. et al 2000, MNRAS, 317, 28
> :
> : * for non Arp-like theories, where the redshift is created in the
> : neighborhood of the galaxy by some gas or plasma, how could the
> : redshift "process" -- whatever it is -- physically generate
> : indentical redshifts at both microwave and optical wavelengths?
> : I.e. all electromagnetic processes I am aware of are highly
> : chromatic.
These points do not apply to my theory as it assume that the redshift
is distance related (i.e. produced progressively on its way from the
object to the observer due to the effect of the intergalactic plasma).
> :
> : * for that matter, how could any "plasma effect" shift the wavelength
> : of emission, without doing other things like line broadening?
> : I.e. why aren't high redshift lines also highly broadened?
This would only apply in case of a scattering, but not for a mechanism
that can be compared to refraction. As shown on my page
http://www.plasmaphysics.org.uk/redshift.htm , the 'blurring' of the
signal can be completely neglected here.
> :
> : * why the cosmic microwave background in the high redshift universe
> : was apparently hotter?
> :
> : Molaro, P., et al. 2002, A&A, 381, L64
> : Silva, A. I. & Viegas, S. M. 2002 MNRAS, 329, 135
> : Srianand, R. Petitjean, P. & Ledoux, C. 2000, Nature, 408, 931
I had a look at two of the papers and I think this should not really
count as hard evidence. There are a lot of assumptions and estimates
being made which are based on observations within our own galaxy and
thus may not be appropriate for QSO's. The excitation of certain fine
structure transitions may well be due to local microwave sources for
instance. Also, they may have underestimated the excitation due to
collisions by electrons by assuming the latter to be in LTE with the
ions and neutrals. This assumption is far from correct for most space
plasmas as photoelectrons usually recombine before they thermalize
owing to their small mass (see for instance my own numerical
calculation for the ionospheric electron spectrum at
http://www.plasmaphysics.org.uk/research/elspec.htm ).
I am also missing any observations that would correspondingly derive a
temperature of 2.7 K from objects within our own galaxy (where the
physical conditions are obviously much better known).
By the way, the observations claim to be consistent with a linear
increase of T with z. Shouldn't photon number conservation during
expansion of the universe require that it increases like z^3?
> :
> : * in NGC 4258, which has maser emissions from a disk of material
> : around the nucleus, both radial (Doppler) and transverse (proper
> : motion) velocity measurements have been made. These follow exactly
> : the profile of a Keplerian disk, but only if the distance is 7.2 +/-
> : 0.3 Mpc. This compares well to the cepheid distance to the galaxy,
> : assuming the Hubble law.
> :
> : Caputo, F., Marconi, M., & Musella, I. 2002, ApJ, 566, 833
> : Herrnstein, J. R. et al. 1999, Nature, 400, 539
> :
> ...
This is another one of these papers that ride on a lot of empirical
approximations, assumptions and estimates and offer little in the way
of a coherent physical argument.
Anyway, I don't understand what it has to do with the redshift problem.
>
> And to move on to your particular theory, as you freely admit, your
> theory is highly wavelength-dependent (dependent on the wavelength of
> radiation vs. the intramolecule spacing of the IGM);
No, my assumption is that this dependence is exactly cancelled by the
proposed 'diffraction limitation' of the effect, i.e. overall there
should not be any wavelength dependence.
>
> The Jupiter test is perhaps most telling, since Jupiter is not really
> hot enough to have a surface plasma, and yet it still deflects light
> in proportion to its mass as GR predicts.
Jupiter (as well as Earth and other planets) are at least 'hot' enough
to have an ionosphere. The argument can therefore be applied here as
well. It is interesting in this context that the gravitional energy of
a hydrogen atom near the surface of Jupiter is about 10 eV which is the
same as the average energy of photoelectrons. So the agreement with GR
regards the mass dependence might be only accidental here (for my
theory at http://www.plasmaphysics.org.uk/research/lensing.htm the
dependence is strict as the electron energy is assumed to be directly
related to the gravitational energy). So unless similar measurements
involving other planets are being made, the Jupiter example is not
really conclusive here.
> Fundamentally, there is no mechanism by which a static electric field
> is known to modify electromagnetic waves; this is a trivial
> application of the superposition principle to Maxwell's Equations [*].
All known mechanisms were unkown at one point, and I am not saying that
the effect I am proposing can be explained in terms of Maxwell's
equations. The point is that it only becomes apparent for astronomical
distances as in the lab field strengths comparable to the inner-atomic
field would be needed.
> You mention casually on one of your web pages some kind of resonance
> between the time-varying electric field of the atom and the frequency
> of the electromagnetic wave. This is, in a sense, what atomic
> lines/transitions are, but these are highly wavelength dependent, and
> do not have the effect of shifting the wavelength of radiation
> continuously (rather, producing absorption or emission lines).
I am not sure what you are referring to here. It seems to have nothing
to do with the redshift/bending effect I suggested (which depends
solely on the static electric field and is thus a non-resonant
phenomenon).
>
> Considering for the moment, that your theory of deflection of
> radiation by electric fields were substantiated (which it's not); and
> your claim of the electric potential of the sun being 1 kV were
> substantiated (which it is not)... It's worth pointing out that the
> static earth potential is over 350 kV, over 350 times your claimed
> potential for the sun (ref. Dolazek). And yet, no significant
> deflection of light is apparent in the earth system. Indeed, the GPS
> system is sensitive at the few millimeter level (i.e. tens of
> *micro*arcseconds for the GPS satellite positions), for which such
> deflections would have been detectable (Wolf & Petit).
>
> Dolezalek, H. "Atmospheric Electricity" CRC Handbook, 67th Ed., p. F-149.
> Wolf, P., & Petit, G. 1997, Phys Rev A, 56, 4405
>
The 350 kV would be only the static potential between the ground and a
height of a couple of km, which corresponds to an electric field of
about 100 V/m in this region. Above this height the field rapidly
decreases. In the ionosphere it is on averagy only of the order of
microVolt/m (although during ionospheric disturbance by high energy
particles it can locally go up to a few milliVolt/m).
Since according to my theory the deflection is proportional to the
square of the size of the region, this means that compared to the sun
the deflection would be reduced by a factor (3km/7*10^5 km)^2 =
2*10^-11. The field is a factor 7*10^7 stronger on the other hand (100
V/m / 1.4*10^-6 V/m) so overall the deflection should be about a factor
10^-3 smaller than for the sun i.e. about 2 milli-arcseconds. This is
not more than the present accuracy of star positions (and anyway it
would not be apparent for stars close together). The effect of this on
the travel time of a GPS signal should be negligible as this angle
corresponds only to a distance of less than the size of an atom over a
height of 3 km.
Thomas
P.S.: I shall be away for a couple of weeks in a few days time, so I
may not have time to further engage in this discussion until next month
Craig Markwardt
Actually, I'm not. You are welcome to investigate cepheids and the
related Hubble key project.
> ... I have covered this on my page
> http://www.physicsmyths.org.uk/redshift.htm . Basically, in general, if
> a 'stretching' of the light wave (by whatever mechanism) leads to a
> redshift, this is also likely to be associated with a reduction of the
> amplitude of the wave i.e. a reduction in its intensity (additionally
> to the usual 1/r^2 decrease). This leads therefore to an
> underestimation of the absolute luminosity of the object.
I note that there is no specific mechanism cited for either the
wavelength "stretching" or amplitude decrease.
So what is this mechanism exactly? Your web page only suggests "if
this were possible" type scenarios, but no specific mechanism. I
suspect that there is no detailed theory behind the wishful scenario.
> > :
> > : * why the cosmic microwave background in the high redshift universe
> > : was apparently hotter?
> > :
> > : Molaro, P., et al. 2002, A&A, 381, L64
> > : Silva, A. I. & Viegas, S. M. 2002 MNRAS, 329, 135
> > : Srianand, R. Petitjean, P. & Ledoux, C. 2000, Nature, 408, 931
>
> I had a look at two of the papers and I think this should not really
> count as hard evidence.
Interesting and ironic, given your own lack of hard evidence.
> ... There are a lot of assumptions and estimates
> being made which are based on observations within our own galaxy and
> thus may not be appropriate for QSO's. ...
Again, interesting in light of your own unsubstantiated assumptions
and estimates. The papers I cited have quite extensive citations
themselves. You could have checked this out, but apparently you did
not.
> ... The excitation of certain fine
> structure transitions may well be due to local microwave sources for
> instance. ...
True, but these papers also consider those possibilities and estimate
the contributions of local sources. Do you have a substantiated
correction to that?
> ... Also, they may have underestimated the excitation due to
> collisions by electrons by assuming the latter to be in LTE with the
> ions and neutrals. This assumption is far from correct for most space
> plasmas as photoelectrons usually recombine before they thermalize
> owing to their small mass (see for instance my own numerical
> calculation for the ionospheric electron spectrum at
> http://www.plasmaphysics.org.uk/research/elspec.htm ).
Some of these factors are discussed in the papers. Meanwhile, you
have provided no quantitative counterargument.
> I am also missing any observations that would correspondingly derive a
> temperature of 2.7 K from objects within our own galaxy (where the
> physical conditions are obviously much better known).
You mean like these?
Herzberg, G. 1950, *Molecular Spectra and Molecular Structure*,
v. 1, 2nd Ed., (van Nostrand: Princeton, NJ) -- p. 496
McKellar, A. 1940 PASP 52, 187
McKellar, A. 1941, Publ Dominion Astrophys. Obs., Victoria, BC, 7, 251
Thaddeus, P. 1972, Ann. Rev. Ast. Ap., 10, 305
I should also mention that the redshift dependence of the CMB
temperature has also been confirmed with galaxy clusters (Battistelli,
E. S., et al. 2002, ApJL, 580, L101).
> By the way, the observations claim to be consistent with a linear
> increase of T with z. Shouldn't photon number conservation during
> expansion of the universe require that it increases like z^3?
References are provided in the papers cited in case you care to
research this matter.
> > : * in NGC 4258, which has maser emissions from a disk of material
> > : around the nucleus, both radial (Doppler) and transverse (proper
> > : motion) velocity measurements have been made. These follow exactly
> > : the profile of a Keplerian disk, but only if the distance is 7.2 +/-
> > : 0.3 Mpc. This compares well to the cepheid distance to the galaxy,
> > : assuming the Hubble law.
> > :
> > : Caputo, F., Marconi, M., & Musella, I. 2002, ApJ, 566, 833
> > : Herrnstein, J. R. et al. 1999, Nature, 400, 539
> > :
> > ...
>
> This is another one of these papers that ride on a lot of empirical
> approximations, assumptions and estimates and offer little in the way
> of a coherent physical argument.
Note, no substantial comments provided.
> Anyway, I don't understand what it has to do with the redshift problem.
It demonstrates that the maser effect and the cepheid distance scale
agree well.
> > And to move on to your particular theory, as you freely admit, your
> > theory is highly wavelength-dependent (dependent on the wavelength of
> > radiation vs. the intramolecule spacing of the IGM);
>
> No, my assumption is that this dependence is exactly cancelled by the
> proposed 'diffraction limitation' of the effect, i.e. overall there
> should not be any wavelength dependence.
Is this a magical mechanism, or is there some substantial theoretical
treatment of how exactly this could occur? I.e. field theory,
experiments, etc.
> > The Jupiter test is perhaps most telling, since Jupiter is not really
> > hot enough to have a surface plasma, and yet it still deflects light
> > in proportion to its mass as GR predicts.
>
> Jupiter (as well as Earth and other planets) are at least 'hot' enough
> to have an ionosphere. The argument can therefore be applied here as
> well. It is interesting in this context that the gravitional energy of
> a hydrogen atom near the surface of Jupiter is about 10 eV which is the
> same as the average energy of photoelectrons. So the agreement with GR
> regards the mass dependence might be only accidental here (for my
> theory at http://www.plasmaphysics.org.uk/research/lensing.htm the
> dependence is strict as the electron energy is assumed to be directly
> related to the gravitational energy). So unless similar measurements
> involving other planets are being made, the Jupiter example is not
> really conclusive here.
So again, do you have a detailed discussion/theory of how an electric
field can bend light rays? Lacking any evidence from you of how large
or extended the so-called Jovian electric field could be, it sounds
like you again have a magic theory.
> > Fundamentally, there is no mechanism by which a static electric field
> > is known to modify electromagnetic waves; this is a trivial
> > application of the superposition principle to Maxwell's Equations [*].
>
> All known mechanisms were unkown at one point, and I am not saying that
> the effect I am proposing can be explained in terms of Maxwell's
> equations. The point is that it only becomes apparent for astronomical
> distances as in the lab field strengths comparable to the inner-atomic
> field would be needed.
I.e. your theory is completely unsubstantiated.
> > You mention casually on one of your web pages some kind of resonance
> > between the time-varying electric field of the atom and the frequency
> > of the electromagnetic wave. This is, in a sense, what atomic
> > lines/transitions are, but these are highly wavelength dependent, and
> > do not have the effect of shifting the wavelength of radiation
> > continuously (rather, producing absorption or emission lines).
>
> I am not sure what you are referring to here. It seems to have nothing
> to do with the redshift/bending effect I suggested (which depends
> solely on the static electric field and is thus a non-resonant
> phenomenon).
Right, so how exactly do static fields exist in intergalactic space?
However, your "theory" is based on an assumption that redshift depends
on wavelength, which it does not. Therefore, it is irrelevant.
CM
Craig Markwardt
"Thomas Smid" <thoma...@gmail.com> writes:
> The redshift mechanism suggested by me would also result on average in
> a linear redshift-distance relationship, so it doesn't make any
> difference for the cepheid observations.
>
> >
> > > ... I have covered this on my page
> > > http://www.physicsmyths.org.uk/redshift.htm . Basically, in general, if
> > > a 'stretching' of the light wave (by whatever mechanism) leads to a
> > > redshift, this is also likely to be associated with a reduction of the
> > > amplitude of the wave i.e. a reduction in its intensity (additionally
> > > to the usual 1/r^2 decrease). This leads therefore to an
> > > underestimation of the absolute luminosity of the object.
> >
> > I note that there is no specific mechanism cited for either the
> > wavelength "stretching" or amplitude decrease.
>
> No there is no mechanism cited, as I assume the effect to be a
> fundamental one, or at least one that can't be derived from presently
> accepted principles (unless you have a suggestion in this sense).
> The exact 'mechanism' could be worked out if the effect is studied in
> more detail. At the moment I am just suggesting, as you said, as a
> possible scenario i.e. that the redshift and bending of light is
> associated with electric fields.
However, since you claim it is a "fundamental" effect, there is no
reason to associate it with electric fields. Why not magnetic fields?
Or for that matter, why not magic pixie dust? Sure, it's easy to
postulate a magic "field" that has exactly the properties of
redshifting and achromatic light bending, but that "field" is in no
way comparable to the known properties of electric
fields. [e.g. "fundamental" principle of linear superposition implies
that electric fields do not interact].
> > > > :
> > > > : * why the cosmic microwave background in the high redshift universe
> > > > : was apparently hotter?
> > > > :
> > > > : Molaro, P., et al. 2002, A&A, 381, L64
> > > > : Silva, A. I. & Viegas, S. M. 2002 MNRAS, 329, 135
> > > > : Srianand, R. Petitjean, P. & Ledoux, C. 2000, Nature, 408, 931
> > >
> > > I had a look at two of the papers and I think this should not really
> > > count as hard evidence.
> >
> > Interesting and ironic, given your own lack of hard evidence.
>
> I am suggesting my theory merely as a proposal, but these papers
> misleadingly suggest that their data would be evidence for an increase
> of the CMB temperature. This is by no means the case as one can see for
> instance from Fig.5 in Srianand et al. (see
> http://www.plasmaphysics.org.uk/imgs/srianand.gif ). I have allowed
> myself here to make this plot somewhat clearer by putting explicit
> error bars to those measurements that merely were estimates of upper
> limits (and I also corrected the figures on the temperature scale which
> originally read 30-20-30). First of all, since the COBE measurement at
> z=0 has nothing to do with the type of analysis at question here, it
> should not serve as further constraint for the data, and without it
> almost any curve could be a fit, for instance a constant temperature of
> 8 K (the long-dashed line that I put in additionally). The latter
> possibility would then of course indicate that the observed fine
> structure excitations are not related to the CMB at all.
Are you really suggesting that the present-day (z=0) cosmic microwave
background temperature is not 2.73 K? Are you really that dense? And
are you aware that the same kinds of techniques used to measure the
CMB temperatures at high redshift were originally used to measure the
local CMB temperature? (see Thaddeus, Herzberg, McKellar references
below, also Roth, Meyer & Hawkins 1993, ApJL 413 L67). And are you
aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
a fit? And, you ignored the other quoted measurements.
> > > ... There are a lot of assumptions and estimates
> > > being made which are based on observations within our own galaxy and
> > > thus may not be appropriate for QSO's. ...
> >
> > Again, interesting in light of your own unsubstantiated assumptions
> > and estimates. The papers I cited have quite extensive citations
> > themselves. You could have checked this out, but apparently you did
> > not.
>
> >
> > > ... The excitation of certain fine
> > > structure transitions may well be due to local microwave sources for
> > > instance. ...
> >
> > True, but these papers also consider those possibilities and estimate
> > the contributions of local sources. Do you have a substantiated
> > correction to that?
> >
> > > ... Also, they may have underestimated the excitation due to
> > > collisions by electrons by assuming the latter to be in LTE with the
> > > ions and neutrals. This assumption is far from correct for most space
> > > plasmas as photoelectrons usually recombine before they thermalize
> > > owing to their small mass (see for instance my own numerical
> > > calculation for the ionospheric electron spectrum at
> > > http://www.plasmaphysics.org.uk/research/elspec.htm ).
> >
> > Some of these factors are discussed in the papers. Meanwhile, you
> > have provided no quantitative counterargument.
>
> The physical assumptions made in these papers are very much
> inappropriate and/or incorrect:
>
> 1) There is no way that photoelectrons of around 10 eV could lose
> sufficient energy such as to end up with a kinetic temperature of
> around 10^-2 eV (100K) (as assumed in these papers). Due to the mass
...
Huh? Since the cited papers deal with excited *fine structure*
states, photoelectrons really have nothing to do with the basic
process. The fine structure states are excited by the CMB.
> 2.) It is assumed in these papers that the fine-structure levels are
> populated according to a Boltzmann distribution. This would require
> that elastic collision time scales are shorter than the life time of
> the levels.
...
Huh^2? Molecular/ionic collisions are not required for the Boltzmann
equation to apply. Since the states in question are directly excited
by the CMB, your comment is irrelevant.
> 3.) The figures used in the papers do in fact not add up at all: in
> Ge,J., Bechtold,J. and Black,J.H. , ApJ. 474, 72 (1997) for instance,
> the H-ionization photon flux appropriate for the observation is given
> as about F= 10^8 ph/cm^2/sec .
...
Since photo-ionization is not the fundamental process in question,
your comment here is also irrelevant. [ However, in some of the
papers, photoionization is discussed as an indirect source of
electrons which make collisions. ]
> > > I am also missing any observations that would correspondingly derive a
> > > temperature of 2.7 K from objects within our own galaxy (where the
> > > physical conditions are obviously much better known).
> >
> > You mean like these?
> >
> > Herzberg, G. 1950, *Molecular Spectra and Molecular Structure*,
> > v. 1, 2nd Ed., (van Nostrand: Princeton, NJ) -- p. 496
> > McKellar, A. 1940 PASP 52, 187
> > McKellar, A. 1941, Publ Dominion Astrophys. Obs., Victoria, BC, 7, 251
> > Thaddeus, P. 1972, Ann. Rev. Ast. Ap., 10, 305
>
> No, actually I meant that the analysis of any of the methods used to
> derive the CMB temperature in certain extragalactic objects is applied
> identically to other objects including ones in our own galaxy. It is in
> my opinion scientifically improper to apply any of these observational
> methods basically only to one instance and then claim that these
> provide mutual confirmation if they happen to yield the expected
> result.
This is not really a relevant critique. For one thing, the "old"
methods of measuring the local CMB noted above are quite similar to
the measurement methods used for the high redshift universe. One of
the primary differences is the species and transition being measured.
However, since the CMB at high redshift is actually a cosmic optical
or UV background, different transitions sensitive to shorter
wavelengths would have needed to be chosen anyway.
> > I should also mention that the redshift dependence of the CMB
> > temperature has also been confirmed with galaxy clusters (Battistelli,
> > E. S., et al. 2002, ApJL, 580, L101).
>
> This is based on the Sunyaev-Zeldovich effect, which I think is not yet
> sufficiently observationally confirmed, because as far as I am a aware,
> the predicted increase of the CMB intensity in the high frequency
> region has not been observed yet at all. ...
It's pretty convenient for you to declare what is sufficiently
observationally confirmed. It's quite impressive that the SZ
measurements to date have confirmed the basic cosmological parameters.
> ... On the other hand, the
> decrease for lower frequencies would also result from my own theory: as
> mentioned already on my page
> http://www.plasmaphysics.org.uk/research/redshift.htm , the plasma
> should lead to electromagnetic waves gradually being 'scrambled' i.e.
> their coherence and thus their apparent intensity being reduced (see
> http://www.plasmaphysics.org.uk/photoionization.htm ). So any
> microwave radiation passing through a cluster would be appear as weaker
> than that not passing through the cluster.
But as noted above, and as you admit yourself, your "theory" is not a
theory at all. It has no independent basis in experiment; is not
borne out or connected to any other theory; it's just wishful
thinking. Meanwhile, the theoretical physics underlying the SZ effect
-- Comptonization -- is well tested and understood.
. . .
I also note that you conveniently deleted several sections of the
previous post.
Recapping those missed points:
* you don't provide any detailed mechanism of how electromagnetic
radiation could be redshifted *or* bent by "electric fields"
* no explanation of how significant static fields could exist
in intergalactic space to cause redshifts
* your "theory" has an implicit dependence on wavelength [*] and yet
cosmological redshift does not
[*] - "it is reasonable to assume that the redshift (as well as
the angular deflection) is not only proportional to the electric
field, but also to the wavelength as the potential difference
between two wave crests is proportional to it."
http://www.plasmaphysics.org.uk/research/lensing.htm
Finally, it is worth noting that while there has long been known to be
a charge separation effect in the sun which produces an electric
potential (Eddington 1926, *The Internal Constitution of Stars*,
Cambridge Press), it is far smaller than you suppose (Neslusan 2001,
A&A, 372 913). Following the very simple derivations therein, the
effect is perhaps 10 Volts, not the 1 kV that you simplistically
derived by setting the gravitational potential energy equal to
electrostatic.
CM
Thomas Smid
Well, if you could show that you can relate both the redshift and the
bending of light to magnetic fields or pixie dust, then this would also
be a theoretical possibility. In contrast to the electric field, I
can't see however how one could plausibly justify these.
>[e.g. "fundamental" principle of linear superposition implies
> that electric fields do not interact].
Light is an electromagnetic field, not just an electric field. It is
known to interact for instance with magnetic fields (e.g. Faraday
rotation), so why should it not also interact with electric fields?
Where did I say this? What I said is that the excitation of the
interstellar molecular fine structure levels has nothing to to with the
CMB temperature.
> And are you aware that the same kinds of techniques used to measure the
> CMB temperatures at high redshift were originally used to measure the
> local CMB temperature? (see Thaddeus, Herzberg, McKellar references
> below, also Roth, Meyer & Hawkins 1993, ApJL 413 L67).
You shouldn't take all claims made in scientific publications at face
value. It is quite obvious that the data analysis in these papers has
been massaged such as to get the desired result. It is for instance
quite revealing that after Penzias and Wilson's discovery of the (then)
3.5 K background radiation in 1965, the value derived from the
observations of the molecular fine structure excitation suddenly went
up from the 2.3 K (as derived by McKellar in 1940) to Penzias and
Wilson's value (e.g. Thaddeus and Clauser, 1966,
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900066961_1990066961.pdf
). Now after the CMB temperature was revised to 2.7 K, suddenly the
lower values are in fashion again. I think everybody can see what is
going on here. The point is that there are so many estimates and
assumptions applied in these papers (most of them questionable in one
way or another) that you can basically derive almost any temperature
from the data if you want.
> And are you
> aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
> a fit?
Well, it does fit the data apparently, but it is hardly a 'best fit'.
Only in the latter case could you rightfully claim that you confirmed
the theoretically predicted increase of the CMB temperatute with z. But
evidently, this is not the case.
No, you are getting this wrong. Photoelectrons of several eV can
excite the upper levels of the observed lines, from which the atom then
decays into the various fine structure levels of the ground state. With
electron energies corresponding to 100 K or so (as assumed in these
papers), this would obviously not be possible.
Anyway, it is in fact nowhere theoretically shown in these papers that
the CMB could lead to any significant population of the fine structure
levels. The method applied there is as follows: they observe a certain
population of the fine structure levels, then they try to estimate (by
means of a host of questionable assumptions) the contributions to the
level population from all other sources *apart* from the CMB, and then,
because they find these are insignificant, conclude that it must be
caused by the CMB (without even having a quantitative theoretical basis
for this suggested mechanism).
>
> > 2.) It is assumed in these papers that the fine-structure levels are
> > populated according to a Boltzmann distribution. This would require
> > that elastic collision time scales are shorter than the life time of
> > the levels.
> ...
>
> Huh^2? Molecular/ionic collisions are not required for the Boltzmann
> equation to apply. Since the states in question are directly excited
> by the CMB, your comment is irrelevant.
Presumably you mean the 'Boltzmann distribution' ('Boltzmann equation'
is something else (see http://www.plasmaphysics.org.uk/#boltzequa )).
The requirement for a Boltzmann distribution (including the ground
state) is a collisionally determined situation (both excitation and
de-excitation). It can in general not be produced by radiation (even a
Planck spectrum would only result in an exponential decrease of the
excited level population in the Wien region of the spectrum; however,
for instance for Carbon the lowest excited fine structure level is only
2*10^-3 eV above the ground state, which would require excitation by a
wavelength of about 0.6 mm i.e. close to the maximum of the 2.7 K
Planck curve (and thus the excitation probability compared to other
levels would not be a simple exponential factor).
>
> > 3.) The figures used in the papers do in fact not add up at all: in
> > Ge,J., Bechtold,J. and Black,J.H. , ApJ. 474, 72 (1997) for instance,
> > the H-ionization photon flux appropriate for the observation is given
> > as about F= 10^8 ph/cm^2/sec .
> ...
>
> Since photo-ionization is not the fundamental process in question,
> your comment here is also irrelevant. [ However, in some of the
> papers, photoionization is discussed as an indirect source of
> electrons which make collisions. ]
Photoionization is dicussed, but obviously if invaild assumptions are
made, the discussion can only lead to incorrect conclusions.
As far as I am aware, the SZ effect has not been confirmed in the Wien
region of the spectrum as yet (where it should lead to an increase of
the CMB intensity rather than a decrease as for the lower frequencies).
I have commented on these points already before.
> Finally, it is worth noting that while there has long been known to be
> a charge separation effect in the sun which produces an electric
> potential (Eddington 1926, *The Internal Constitution of Stars*,
> Cambridge Press), it is far smaller than you suppose (Neslusan 2001,
> A&A, 372 913). Following the very simple derivations therein, the
> effect is perhaps 10 Volts, not the 1 kV that you simplistically
> derived by setting the gravitational potential energy equal to
> electrostatic.
Where do you get the 10 Volts from? The paper (
http://www.edpsciences.org/articles/aa/pdf/2001/24/aah2649.pdf )
arrives at the result that the electric force corresponds to 50% of the
gravitational force for protons. Now the gravitational energy of a
proton near the sun's surface is 2 keV i.e. the electric potential is 1
kV according to this as well.
Thomas
Craig Markwardt
> bending of light to magnetic fields or pixie dust, then this would also
> be a theoretical possibility. In contrast to the electric field, I
> can't see however how one could plausibly justify these.
However, since you have no plausible mechanism to cause electric
fields to interact with electromagnetic waves -- other than to claim
that it is "fundamental" -- it is just is well to substitute magnetic
fields or pixie dust. You seem to be arguing based on plausibility,
but there is no known interaction to base that plausibility on, so
your basis is irrelevant.
> [e.g. "fundamental" principle of linear superposition implies
> > that electric fields do not interact].
>
> Light is an electromagnetic field, not just an electric field. It is
> known to interact for instance with magnetic fields (e.g. Faraday
> rotation), so why should it not also interact with electric fields?
Since electromagnetic waves do not interact with isolated magnetic
fields, your analogy is flawed. Faraday rotation requires the
presence of a birefringent medium. You made the claim: the burden is
upon *you* to show how electric fields could interact with
electromagnetic waves.
> Where did I say this? What I said is that the excitation of the
> interstellar molecular fine structure levels has nothing to to with the
> CMB temperature.
Nevertheless, in a plot of temperature vs. redshift, one cannot deny
that the present-day CMB temperature is 2.73 degrees. And by the way,
this is not just a COBE/FIRAS measurement. There are also WMAP
results and observations of excited hyperfine states of molecules
(Roth, Meyer & Hawkins 1993, ApJL 413 L67), plus numerous balloon
experiments. T=2.73 is clearly the anchor of that plot at z=0.
> > And are you aware that the same kinds of techniques used to measure the
> > CMB temperatures at high redshift were originally used to measure the
> > local CMB temperature? (see Thaddeus, Herzberg, McKellar references
> > below, also Roth, Meyer & Hawkins 1993, ApJL 413 L67).
>
> You shouldn't take everything for face value you read in scientific
> publications. It is quite obvious that the data analysis in these
> papers has been massaged such as to get the desired result.
And, not knowing it in advance, what exactly was the desired result?
[ It is worth mentioning that there were quite widely differing
theoretical predictions for the CMB temperature. ]
> ... It is for
> instance quite revealing that after Penzias and Wilson's discovery of
> the (then) 3.5 K background radiation in 1965, the value derived from
> the observations of the molecular fine structure excitation suddenly
> went up from the 2.3 K (as derived by McKellar in 1940) to Penzias and
> Wilson's value (e.g. Thaddeus and Clauser, 1966,
> http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900066961_1990066961.pdf
> ). Now after the CMB temperature was revised to 2.7 K, suddenly the
> lower values are in fashion again. I think everybody can see what is
> going on here. The point is that there are so many estimates and
> assumptions applied in these papers (most of them questionable in one
> way or another) that you can basically derive almost any temperature
> from the data if you want.
Really? Let's look at the results.
McKellar (1941) derives a value of 2.3 K from CN, but with unknown
uncertainties (I do not have access to the primary source), but it
is fair to say that McKellar (1940) finds a range of 2.1-2.7 K.
Penzias & Wilson 1965, ApJ, 142, 419, found 3.5 +/- 0.5 K
via direct measurement.
The Thaddeus & Clauser paper you refer to (1966, PRL, 16, 819)
quotes values of 3.75 +/- 0.5 using CN.
Field & Hitchcock, 1966, ApJ, 146, 1, find 3.22+/-0.15 and 3.0+/-0.6 for
two different stars using CN.
Thaddeus (1972) ARA&A, points out that the weighted mean of all CN
measurements to that time was 2.78 +/- 0.10 K.
Roth, Meyer & Hawkins 1993, ApJL 413 L67, find 2.729 +/- 0.030 K,
using a compilation of sensitive CN measurements.
What you are noting is fluctuations due to measurement uncertainties,
which for the early experiments are large. The weighted average of
the early results is consistent with the modern CN measurements, and
modern direct measurements. This is also noted by Ned Wright
(http://www.astro.ucla.edu/~wright/CMB.html), although it is plotted
against frequency, not publication date.
So, NO one *cannot* derive any temperature that you want. Your claim
is erroneous.
> > And are you
> > aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
> > a fit?
>
> Well, it does fit the data apparently, but it is hardly a 'best fit'.
> Only in the latter case could you rightfully claim that you confirmed
> the theoretically predicted increase of the CMB temperatute with z. But
> evidently, this is not the case.
Huh? There is no requirement to make a "best fit" in order to claim
consistency with a theory, so your claim is erroneous. For example,
the chi-square null hypothesis test is valid with or without fitting.
That fact that the observational result is consistent with the model
with *no fitting at all* is a powerful statement. And of course, you
are neglecting the other measurements cited.
> No, you are getting this wrong. Photoelectrons of several eV can
> excite the upper levels of the observed lines, from which the atom then
> decays into the various fine structure levels of the ground state. With
> electron energies corresponding to 100 K or so (as assumed in these
> papers), this would obviously not be possible.
Again, huh? First of all, lines do not have "upper levels." Second
of all, these transitions observed in *absorption*, so there are no
photo-electrons or cascades involved. Thus, your argument is
irrelevant.
> Anyway, it is in fact nowhere theoretically shown in these papers that
> the CMB could lead to any significant population of the fine structure
> levels. ...
Yet again, huh? First of all, the papers and references therein
explain quite well the observations, the atoms and molecules, the
states, and the nature of the excitation by the CMB. Of course, it's
basic quantum physics, the kind that has been understood for almost a
century.
> ... The method applied there is as follows: they observe a certain
> population of the fine structure levels, then they try to estimate (by
> means of a host of questionable assumptions) the contributions to the
> level population from all other sources *apart* from the CMB, and then,
> because they find these are insignificant, conclude that it must be
> caused by the CMB (without even having a quantitative theoretical basis
> for this suggested mechanism).
You must have neglected to read the papers, since they (and the
references therein) discuss the physics in great (quantitative)
detail. And of course, subtracting known (though perhaps uncertain)
biases is the proper procedure: it is better than reporting biased
values. Thus, your criticisms are unwarranted.
> > > 2.) It is assumed in these papers that the fine-structure levels are
> > > populated according to a Boltzmann distribution. This would require
> > > that elastic collision time scales are shorter than the life time of
> > > the levels.
> > ...
> >
> > Huh^2? Molecular/ionic collisions are not required for the Boltzmann
> > equation to apply. Since the states in question are directly excited
> > by the CMB, your comment is irrelevant.
>
> Presumably you mean the 'Boltzmann distribution' ('Boltzmann equation'
> is something else (see http://www.plasmaphysics.org.uk/#boltzequa )).
True.
However, it should be mentioned that your original criticism was
incorrect. All of the papers cited do not assume a
Boltzmann-distribution for the fine structure levels. Rather, the
populations are computed by detailed balance. The one paper that
*you* cited (Ge Bechtold & Black 1997) considers the Boltzmann
equation to form an *upper limit* to the CMB temperature, but then
considers other effects which can change the balance.
> > > 3.) The figures used in the papers do in fact not add up at all: in
> > > Ge,J., Bechtold,J. and Black,J.H. , ApJ. 474, 72 (1997) for instance,
> > > the H-ionization photon flux appropriate for the observation is given
> > > as about F= 10^8 ph/cm^2/sec .
> > ...
> >
> > Since photo-ionization is not the fundamental process in question,
> > your comment here is also irrelevant. [ However, in some of the
> > papers, photoionization is discussed as an indirect source of
> > electrons which make collisions. ]
>
> Photoionization is dicussed, but obviously if invaild assumptions are
> made, the discussion can only lead to incorrect conclusions.
True. However, since the constraints are based on a detailed and
verified photoionization model, matched to the observations, your
concerns are largely irrelevant.
> > > > > I am also missing any observations that would correspondingly derive a
> > > > > temperature of 2.7 K from objects within our own galaxy (where the
> > > > > physical conditions are obviously much better known).
> > > >
> > > > You mean like these?
> > > >
> > > > Herzberg, G. 1950, *Molecular Spectra and Molecular Structure*,
> > > > v. 1, 2nd Ed., (van Nostrand: Princeton, NJ) -- p. 496
> > > > McKellar, A. 1940 PASP 52, 187
> > > > McKellar, A. 1941, Publ Dominion Astrophys. Obs., Victoria, BC, 7, 251
> > > > Thaddeus, P. 1972, Ann. Rev. Ast. Ap., 10, 305
> > >
> > > No, actually I meant that the analysis of any of the methods used to
> > > derive the CMB temperature in certain extragalactic objects is applied
> > > identically to other objects including ones in our own galaxy. It is in
> > > my opinion scientifically improper to apply any of these observational
> > > methods basically only to one instance and then claim that these
> > > provide mutual confirmation if they happen to yield the expected
> > > result.
> >
> > This is not really a relevant critique. For one thing, the "old"
> > methods of measuring the local CMB noted above are quite similar to
> > the measurement methods used for the high redshift universe. One of
> > the primary differences is the species and transition being measured.
> > However, since the CMB at high redshift is actually a cosmic optical
> > or UV background, different transitions sensitive to shorter
> > wavelengths would have needed to be chosen anyway.
Note, no response.
> > > > I should also mention that the redshift dependence of the CMB
> > > > temperature has also been confirmed with galaxy clusters (Battistelli,
> > > > E. S., et al. 2002, ApJL, 580, L101).
> > >
> > > This is based on the Sunyaev-Zeldovich effect, which I think is not yet
> > > sufficiently observationally confirmed, because as far as I am a aware,
> > > the predicted increase of the CMB intensity in the high frequency
> > > region has not been observed yet at all. ...
> >
> > It's pretty convenient for you to declare what is sufficiently
> > observationally confirmed. It's quite impressive that the SZ
> > measurements to date have confirmed the basic cosmological parameters.
>
> As far as I am aware, the SZ effect has not been confirmed in the Wien
> region of the spectrum as yet (where it should lead to an increase of
> the CMB intensity rather than a decrease as for the lower frequencies).
Kudos to your awareness. However, the lack of experimental
confirmation of all aspects of a theory does not negate the theory
(and unlike the observed SZ decrement, the detection of an increment
would be in a region of the EM spectrum which is extremely difficult
to observe).
> > > ... On the other hand, the
> > > decrease for lower frequencies would also result from my own theory: as
> > > mentioned already on my page
> > > http://www.plasmaphysics.org.uk/research/redshift.htm , the plasma
> > > should lead to electromagnetic waves gradually being 'scrambled' i.e.
> > > their coherence and thus their apparent intensity being reduced (see
> > > http://www.plasmaphysics.org.uk/photoionization.htm ). So any
> > > microwave radiation passing through a cluster would be appear as weaker
> > > than that not passing through the cluster.
> >
> > But as noted above, and as you admit yourself, your "theory" is not a
> > theory at all. It has no independent basis in experiment; is not
> > borne out or connected to any other theory; it's just wishful
> > thinking. Meanwhile, the theoretical physics underlying the SZ effect
> > -- Comptonization -- is well tested and understood.
Note: no response.
> >
> > . . .
> >
> > I also note that you conveniently deleted several sections of the
> > previous post.
> > Recapping those missed points:
> > * you don't provide any detailed mechanism of how electromagnetic
> > radiation could be redshifted *or* bent by "electric fields"
> > * no explanation of how significant static fields could exist
> > in intergalactic space to cause redshifts
> > * your "theory" has an implicit dependence on wavelength [*] and yet
> > cosmological redshift does not
> > [*] - "it is reasonable to assume that the redshift (as well as
> > the angular deflection) is not only proportional to the electric
> > field, but also to the wavelength as the potential difference
> > between two wave crests is proportional to it."
> > http://www.plasmaphysics.org.uk/research/lensing.htm
>
> I have commented on these points already before.
Let's see.
* regarding point #1, your only "comment" has been that somehow the
electric field interaction is "fundamental."
* regarding point #2, you have made no comment.
* regarding point #3, you have left your own self-contradiction
unresolved. You want it both ways: wavelength independence, to
agree with redshift measurements; but also wavelength dependence
as quoted above.
I retract my Neslusan assertion.
I see that you continue to provide unsubstantiated and wildly
speculative assertions.
CM
Thomas Smid
> Since electromagnetic waves do not interact with isolated magnetic
> fields, your analogy is flawed. Faraday rotation requires the
> presence of a birefringent medium. You made the claim: the burden is
> upon *you* to show how electric fields could interact with
> electromagnetic waves.
First of all, I wouldn't be so sure that electromagnetic waves don't
interact with isolated magnetic fields. The interaction might be so
weak that it is only observable for sufficiently strong fields.
But anyway, even if a birefringent medium is required, you seem to
forget that it is only the electrostatic/magnetostatic properties of
the medium that are responsible for the Faraday rotation. There is
nothing else to it. So it is clearly incorrect to say that electric
fields don't interact with electromagnetic waves.
> Really? Let's look at the results.
> McKellar (1941) derives a value of 2.3 K from CN, but with unknown
> uncertainties (I do not have access to the primary source), but it
> is fair to say that McKellar (1940) finds a range of 2.1-2.7 K.
> Penzias & Wilson 1965, ApJ, 142, 419, found 3.5 +/- 0.5 K
> via direct measurement.
> The Thaddeus & Clauser paper you refer to (1966, PRL, 16, 819)
> quotes values of 3.75 +/- 0.5 using CN.
> Field & Hitchcock, 1966, ApJ, 146, 1, find 3.22+/-0.15 and 3.0+/-0.6 for
> two different stars using CN.
> Thaddeus (1972) ARA&A, points out that the weighted mean of all CN
> measurements to that time was 2.78 +/- 0.10 K.
> Roth, Meyer & Hawkins 1993, ApJL 413 L67, find 2.729 +/- 0.030 K,
> using a compilation of sensitive CN measurements.
>
> What you are noting is fluctuations due to measurement uncertainties,
> which for the early experiments are large. The weighted average of
> the early results is consistent with the modern CN measurements, and
> modern direct measurements. This is also noted by Ned Wright
> (http://www.astro.ucla.edu/~wright/CMB.html), although it is plotted
> against frequency, not publication date.
>
> So, NO one *cannot* derive any temperature that you want. Your claim
> is erroneous.
>
> > > And are you
> > > aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
> > > a fit?
> >
> > Well, it does fit the data apparently, but it is hardly a 'best fit'.
> > Only in the latter case could you rightfully claim that you confirmed
> > the theoretically predicted increase of the CMB temperatute with z. But
> > evidently, this is not the case.
>
> Huh? There is no requirement to make a "best fit" in order to claim
> consistency with a theory, so your claim is erroneous. For example,
> the chi-square null hypothesis test is valid with or without fitting.
> That fact that the observational result is consistent with the model
> with *no fitting at all* is a powerful statement.
Looking at the plot that Srianand et al. produced (see
http://www.plasmaphysics.org.uk/imgs/srianand.gif ), I think it is more
a pitiful than a powerful statement. It is obvious in this case (and
others as well) that the theoretical prediction is only consistent with
the data due to the poor quality of the latter (not to mention all the
questionable physical assumptions that have gone into the analysis).
In view of this, it is quite misleading to claim that the data confirm
the predictions of Big-Bang cosmology. They don't, because they could
confirm any other theoretical scenario as well. Plotting the 2.73
*(1+z) through the data is merely wishful thinking and has in my
opinion nothing to do with proper science.
> > > >
> > > > 1) There is no way that photoelectrons of around 10 eV could lose
> > > > sufficient energy such as to end up with a kinetic temperature of
> > > > around 10^-2 eV (100K) (as assumed in these papers). Due to the mass
> > > ...
> > >
> > > Huh? Since the cited papers deal with excited *fine structure*
> > > states, photoelectrons really have nothing to do with the basic
> > > process. The fine structure states are excited by the CMB.
> >
> > No, you are getting this wrong. Photoelectrons of several eV can
> > excite the upper levels of the observed lines, from which the atom then
> > decays into the various fine structure levels of the ground state. With
> > electron energies corresponding to 100 K or so (as assumed in these
> > papers), this would obviously not be possible.
>
> Again, huh? First of all, lines do not have "upper levels." Second
> of all, these transitions observed in *absorption*, so there are no
> photo-electrons or cascades involved. Thus, your argument is
> irrelevant.
Any line (i.e. atomic transition) has an upper and lower level.
Electrons of sufficient energy can excite atoms from the ground state
to an excited state (upper level) which then decay into lower lying
states from where they are observable in absorption (in these papers
this 'pumping' mechanism is actually discussed, but only for UV
radiation, not photoelectrons).
>
>
> > Anyway, it is in fact nowhere theoretically shown in these papers that
> > the CMB could lead to any significant population of the fine structure
> > levels. ...
>
> Yet again, huh? First of all, the papers and references therein
> explain quite well the observations, the atoms and molecules, the
> states, and the nature of the excitation by the CMB. Of course, it's
> basic quantum physics, the kind that has been understood for almost a
> century.
>
> > ... The method applied there is as follows: they observe a certain
> > population of the fine structure levels, then they try to estimate (by
> > means of a host of questionable assumptions) the contributions to the
> > level population from all other sources *apart* from the CMB, and then,
> > because they find these are insignificant, conclude that it must be
> > caused by the CMB (without even having a quantitative theoretical basis
> > for this suggested mechanism).
>
> You must have neglected to read the papers, since they (and the
> references therein) discuss the physics in great (quantitative)
> detail. And of course, subtracting known (though perhaps uncertain)
> biases is the proper procedure: it is better than reporting biased
> values. Thus, your criticisms are unwarranted.
As I said, the excitation rates due to the CMB is not explicitly
calculated in these papers. They assume a Boltzmann distribution for
the population of the fine structure levels and on the basis of this
they derive an 'excitation temperature' from the observations. Then
they estimate what contribution to this excitation temperature a number
of other mechanisms make and conclude that the remainder must be due
to the CMB. Nowhere is the proposed excitation due to the CMB actually
theoretically discussed in any way.
Thomas
Craig Markwardt
"Thomas Smid" <thoma...@gmail.com> writes:
> Craig Markwardt wrote:
>
> > Since electromagnetic waves do not interact with isolated magnetic
> > fields, your analogy is flawed. Faraday rotation requires the
> > presence of a birefringent medium. You made the claim: the burden is
> > upon *you* to show how electric fields could interact with
> > electromagnetic waves.
>
> interact with isolated magnetic fields. The interaction might be so
> weak that it is only observable for sufficiently strong fields.
Hold on a second, now you are using an unsubstantiated claim about
magnetic fields to support your previous unsubstantiated claim about
electric fields? Ridiculous.
The fact still holds: Maxwell's equations are linear. The
superposition of an electromagnetic wave and an electrostatic (or
magnetostatic) field in a vacuum causes no interaction. Your claim
that electric fields are more "plausible" than magnetic fields or
magic pixie dust are entirely unsubtantiated, since they are all
equally implausible.
> But anyway, even if a birefringent medium is required, you seem to
> forget that it is only the electrostatic/magnetostatic properties of
> the medium that are responsible for the Faraday rotation. There is
> nothing else to it. So it is clearly incorrect to say that electric
> fields don't interact with electromagnetic waves.
Huh? Your logic is muddled.
Let's review the well known effects of a plasma and gas on
electromagnetic radiation:
1. Radio signals are dispersed in time.
The strength of the dispersion is a highly wavelength-dependent
effect, inconsistent with redshift or light bending, which are
achromatic. The radio wavelength is invariant.
2. Potential Faraday rotation of radio signals by plasma in magnetic field.
The strength of the rotation is highly wavelength dependent and
dependent on the density of the plasma and the magnetic field,
all of which are inconsistent with redshift or light bending, which
are achoromatic, and independent of the plasma column density.
The radio wavelength is invariant.
3. Absorption lines
Highly wavelength dependent, inconsistent with redshift or light
bending, which are achromatic. The wavelength of the underlying
spectrum is invariant.
4. Absorption continuum
Highly wavelength dependent, inconsistent with redshift or light
bending, which are achromatic. The wavelength of the underlying
spectrum is invariant.
All of these plasma effects are totally inconsistent with redshift or
light bending, primarily because the plasma effects are highly
chromatic, whereas the GR effects are not, and most importantly, none
of these effects changes the wavelength of the radiation passing
through!
Instead, you posit some mysterious "fundamental" interaction between
electric fields and electromagnetic waves which has *just the right*
behavior [*]... but absolutely no substantiation in theory or
experiment. I'm sure that's great for you, but it's irrelevant to the
rest of the world.
[*] except when you define the electric field effect to be
wavelength dependent and wavelength independent at the same time.
Self-contradiction is not a good sign in any theory.
> > Really? Let's look at the results.
> > McKellar (1941) derives a value of 2.3 K from CN, but with unknown
> > uncertainties (I do not have access to the primary source), but it
> > is fair to say that McKellar (1940) finds a range of 2.1-2.7 K.
> > Penzias & Wilson 1965, ApJ, 142, 419, found 3.5 +/- 0.5 K
> > via direct measurement.
> > The Thaddeus & Clauser paper you refer to (1966, PRL, 16, 819)
> > quotes values of 3.75 +/- 0.5 using CN.
> > Field & Hitchcock, 1966, ApJ, 146, 1, find 3.22+/-0.15 and 3.0+/-0.6 for
> > two different stars using CN.
> > Thaddeus (1972) ARA&A, points out that the weighted mean of all CN
> > measurements to that time was 2.78 +/- 0.10 K.
> > Roth, Meyer & Hawkins 1993, ApJL 413 L67, find 2.729 +/- 0.030 K,
> > using a compilation of sensitive CN measurements.
> >
> > What you are noting is fluctuations due to measurement uncertainties,
> > which for the early experiments are large. The weighted average of
> > the early results is consistent with the modern CN measurements, and
> > modern direct measurements. This is also noted by Ned Wright
> > (http://www.astro.ucla.edu/~wright/CMB.html), although it is plotted
> > against frequency, not publication date.
> >
> > So, NO one *cannot* derive any temperature that you want. Your claim
> > is erroneous.
Note, no response.
> > > > And are you
> > > > aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
> > > > a fit?
> > >
> > > Well, it does fit the data apparently, but it is hardly a 'best fit'.
> > > Only in the latter case could you rightfully claim that you confirmed
> > > the theoretically predicted increase of the CMB temperatute with z. But
> > > evidently, this is not the case.
> >
> > Huh? There is no requirement to make a "best fit" in order to claim
> > consistency with a theory, so your claim is erroneous. For example,
> > the chi-square null hypothesis test is valid with or without fitting.
> > That fact that the observational result is consistent with the model
> > with *no fitting at all* is a powerful statement.
>
> Looking at the plot that Srianand et al. produced (see
> http://www.plasmaphysics.org.uk/imgs/srianand.gif ), I think it is more
> a pitiful than a powerful statement. It is obvious in this case (and
> others as well) that the theoretical prediction is only consistent with
> the data due to the poor quality of the latter (not to mention all the
> questionable physical assumptions that have gone into the analysis).
> In view of this, it is quite misleading to claim that the data confirm
> the predictions of Big-Bang cosmology. They don't, because they could
> confirm any other theoretical scenario as well. Plotting the 2.73
> *(1+z) through the data is merely wishful thinking and has in my
> opinion nothing to do with proper science.
Really? Let's look at some other scenarios.
What about T(z) = 2.73*(1+z)^2 ? Ruled out.
What about T(z) = 2.73*(1+z)^3 ? Ruled out.
What about T(z) = 2.73*(1+z)^4 ? Ruled out.
What about T(z) = 2.73*exp(z) ? Ruled out.
What about T(z) = 2.73/(1+z) ? Ruled out.
What about T(z) = 2.73 ? Ruled out. (with low confidence)
So in fact it rules out a lot of possibilities -- "any other
theoretical scenario" is *not* possible. So yet again, you have
issued an unsubstantiated claim.
> > > > > 1) There is no way that photoelectrons of around 10 eV could lose
> > > > > sufficient energy such as to end up with a kinetic temperature of
> > > > > around 10^-2 eV (100K) (as assumed in these papers). Due to the mass
> > > > ...
> > > >
> > > > Huh? Since the cited papers deal with excited *fine structure*
> > > > states, photoelectrons really have nothing to do with the basic
> > > > process. The fine structure states are excited by the CMB.
> > >
> > > No, you are getting this wrong. Photoelectrons of several eV can
> > > excite the upper levels of the observed lines, from which the atom then
> > > decays into the various fine structure levels of the ground state. With
> > > electron energies corresponding to 100 K or so (as assumed in these
> > > papers), this would obviously not be possible.
> >
> > Again, huh? First of all, lines do not have "upper levels." Second
> > of all, these transitions observed in *absorption*, so there are no
> > photo-electrons or cascades involved. Thus, your argument is
> > irrelevant.
>
> Any line (i.e. atomic transition) has an upper and lower level.
> Electrons of sufficient energy can excite atoms from the ground state
> to an excited state (upper level) which then decay into lower lying
> states from where they are observable in absorption (in these papers
> this 'pumping' mechanism is actually discussed, but only for UV
> radiation, not photoelectrons).
I misunderstood your statement. However, it is still irrelevant for
the reasons stated. Your 10 eV vs. 0.01 eV criticism is a canard.
Since the transitions are seen in *absorption* there is no need for
any photoelectrons "losing energy." I note that you did not address
this.
> > > Anyway, it is in fact nowhere theoretically shown in these papers that
> > > the CMB could lead to any significant population of the fine structure
> > > levels. ...
> >
> > Yet again, huh? First of all, the papers and references therein
> > explain quite well the observations, the atoms and molecules, the
> > states, and the nature of the excitation by the CMB. Of course, it's
> > basic quantum physics, the kind that has been understood for almost a
> > century.
> >
> > > ... The method applied there is as follows: they observe a certain
> > > population of the fine structure levels, then they try to estimate (by
> > > means of a host of questionable assumptions) the contributions to the
> > > level population from all other sources *apart* from the CMB, and then,
> > > because they find these are insignificant, conclude that it must be
> > > caused by the CMB (without even having a quantitative theoretical basis
> > > for this suggested mechanism).
> >
> > You must have neglected to read the papers, since they (and the
> > references therein) discuss the physics in great (quantitative)
> > detail. And of course, subtracting known (though perhaps uncertain)
> > biases is the proper procedure: it is better than reporting biased
> > values. Thus, your criticisms are unwarranted.
>
> As I said, the excitation rates due to the CMB is not explicity
> calculated in these papers. They assume a Boltzmann distribution for
> the population of the fine structure levels and on the basis of this
> they derive an 'excitation temperature' from the observations. Then
> they estimate what contribution to this excitation temperature a number
> of other mechanisms make and conclude that the remainder must be due
> to the CMB. Nowhere is the proposed excitation due to the CMB actually
> theoretically discussed in any way.
Really? Let's look.
Srianand et al. refer to Meyer et al 1986, ApJL 308, L37 for calculations
Does it assume a Boltzmann distribution?
--> YES, to set an upper limit on the CMBR temperature
--> NO, after considering detailed balance of all processes
Molaro et al. have an extensive description including equations (eq
1&2) and figure (Fig 1)
Does it assume a Boltzmann distribution?
--> YES, to set an upper limit on the CMBR temperature
--> NO, after considering detailed balance of all processes
Silva & Viegas contains detailed modeling, including excitation
rates of the relevant transitions due the CMBR at various
temperatures, and full detailed balance calculations
Does it assume a Boltzmann distribution? --> NO
Your claims continue to be erroneous and unsubstantiated.
You also conveniently deleted several parts of the previous post.
[ Smid: ]
> As far as I am aware, the SZ effect has not been confirmed in the Wien
> region of the spectrum as yet (where it should lead to an increase of
> the CMB intensity rather than a decrease as for the lower frequencies).
[ Markwardt: ]
: Kudos to your awareness. However, the lack of experimental
: confirmation of all aspects of a theory does not negate the theory
: (and unlike the observed SZ decrement, the detection of an increment
: would be in a region of the EM spectrum which is extremely difficult
: to observe).
I note no response.
[ Markwardt: ]
: But as noted above, and as you admit yourself, your "theory" is not a
: theory at all. It has no independent basis in experiment; is not
: borne out or connected to any other theory; it's just wishful
: thinking. Meanwhile, the theoretical physics underlying the SZ effect
: -- Comptonization -- is well tested and understood.
I note a continued lack of response.
[ Markwardt: ]
: I also note that you conveniently deleted several sections of the
: previous post.
: Recapping those missed points:
: * you don't provide any detailed mechanism of how electromagnetic
: radiation could be redshifted *or* bent by "electric fields"
: * no explanation of how significant static fields could exist
: in intergalactic space to cause redshifts
: * your "theory" has an implicit dependence on wavelength [*] and yet
: cosmological redshift does not
: [*] - "it is reasonable to assume that the redshift (as well as
: the angular deflection) is not only proportional to the electric
: field, but also to the wavelength as the potential difference
: between two wave crests is proportional to it."
: http://www.plasmaphysics.org.uk/research/lensing.htm
[ Smid: ]
> I have commented on these points already before.
[ Markwardt: ]
: Let's see.
:
: * regarding point #1, your only "comment" has been that somehow the
: electric field interaction is "fundamental."
:
: * regarding point #2, you have made no comment.
:
: * regarding point #3, you have left your own self-contradiction
: unresolved. You want it both ways: wavelength independence, to
: agree with redshift measurements; but also wavelength dependence
: as quoted above.
I note, a continued lack of response.
Given your continual erroneous speculations and unsubstantiated
claims, it's not really worth my time to continue this thread.
CM
Thomas Smid
You are referring to mechanisms that have nothing to do with the one I
am suggesting (for which there would not be an overall wavelength
dependence as mentioned before).
Your original argument was that there is no interaction between
electrostatic/magnetostatic fields and electromagnetic waves per se.
This is clearly incorrect as it would imply that light would not
interact with matter at all, i.e. we would have no refraction, Faraday
rotation etc.
>
> Instead, you posit some mysterious "fundamental" interaction between
> electric fields and electromagnetic waves which has *just the right*
> behavior [*]... but absolutely no substantiation in theory or
> experiment. I'm sure that's great for you, but it's irrelevant to the
> rest of the world.
If your attitude is 'I don't care about what I don't know' then you
shouldn't be working in science.
I indicated above already another possibility (T=8K) in
http://www.plasmaphysics.org.uk/imgs/srianand.gif (which fits the
data if you ignore the unrelated COBE measurement).
I don't know what you mean. Again, excitation of higher levels by
photoelectrons will necessarily increase the population of the lower
levels as the former are de-excited. This would thus directly affect
the strength of the absorption lines observed.
The use of an 'excitation temperature' to describe the population of
the levels proves that they assume LTE conditions i.e. a Boltzmann
distribution.
>
> Molaro et al. have an extensive description including equations (eq
> 1&2) and figure (Fig 1)
> Does it assume a Boltzmann distribution?
> --> YES, to set an upper limit on the CMBR temperature
> --> NO, after considering detailed balance of all processes
Again, the use of an 'excitation temperature' to describe the
population of the levels proves that they assume LTE conditions i.e. a
Boltzmann distribution.
>
> Silva & Viegas contains detailed modeling, including excitation
> rates of the relevant transitions due the CMBR at various
> temperatures, and full detailed balance calculations
> Does it assume a Boltzmann distribution? --> NO
I quote from the paper (section 2 near Eq.(6)): 'The fine structure
levels may also be directly populated by the CMBR. In that case one
must add to the energy densities a contribution from a blackbody
radiation field redshifted to a temperature T=T0*(1+z). .....**We
caution however that this relation remains yet observationally
unproven**'.
The latter remark is not too surprising looking at the results of their
data analysis (see
http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ). This very much
resembles the inconclusive result obtained by Srianand et al (
http://www.plasmaphysics.org.uk/imgs/srianand.gif ) . In fact it is
even worse as near about z=2, there are several data points that are
mutually exclusive and could not possibly fit any curve. This very much
indicates that the excitation of the fine structure levels is in fact
not related to the CMBR at all. This is also further confirmed by
certain inconsistencies in the paper:
from Table 1 it follows that the excitation rate due to the CMBR into
the second fine structure level is many orders of magnitudes smaller
than that into the first (8 orders of magnitude for z=2). This should
be directly reflected in the corresponding level population due to the
CMBR. However, Fig.2 suggests that the population ratio is reduced by
merely about one order of magnitude (with even for the second level,
the contribution due to the CMBR exceeding that due to collisions).
There is also a puzzling verbal inconsistency: the theory section
suggests that the CMBR is taken explicitly into account for determining
the level population (see the quote at the top of this paragraph), but
then right at the bottom of paragraph 2.2 they say: 'The model
presented here should allow the inclusion of excitation by the CMBR'.
This suggests that they actually did not consider it consistently
together with the other excitation mechanism, but merely added it by
means of some ad-hoc assumptions associated with the observed level
populations and the theoretical predictions for the other mechanisms.
This shows clearly that these papers should not be taken seriously.
You should pay better attention to what I am saying and maybe think
about it for a second before you reply. This would save as both a lot
of time.
>
> Given your continual erroneous speculations and unsubstantiated
> claims, it's not really worth my time to continue this thread.
Just as well given the insubstantial nature of your arguments.
Thomas
Craig Markwardt
"Thomas Smid" <thoma...@gmail.com> writes:
> Craig Markwardt wrote:
>
> > "Thomas Smid" <thoma...@gmail.com> writes:
> > > Craig Markwardt wrote:
> > >
> > > > Since electromagnetic waves do not interact with isolated magnetic
> > > > fields, your analogy is flawed. Faraday rotation requires the
> > > > presence of a birefringent medium. You made the claim: the burden is
> > > > upon *you* to show how electric fields could interact with
> > > > electromagnetic waves.
> > >
> > > First of all, I wouldn't be so sure that electromagnetic waves don't
> > > interact with isolated magnetic fields. The interaction might be so
> > > weak that it is only observable for sufficiently strong fields.
> >
> > Hold on a second, now you are using an unsubstantiated claim about
> > magnetic fields to support your previous unsubstantiated claim about
> > electric fields? Ridiculous.
I note no response.
Precisely. All the well known electromagnetic interactions with
matter are highly chromatic. Your suggested electric field
"mechanism" is not chromatic, which also suggests that it is wrong.
But wait, you simultaneously suggest that your "mechanism" does not
have a wavelength dependence (see above), *AND* that it *DOES* have a
wavelength dependence,
"First of all, it is reasonable to assume that the redshift (as well
as the angular deflection) is not only proportional to the electric
field, but also to the wavelength as the potential difference
between two wave crests is proportional to it."
http://www.plasmaphysics.org.uk/research/lensing.htm
I note that despite this inconsistency being brought to your attention
multiple times, you continue to ignore it. As your theory is
self-contradictory, it is irrelevant.
Not to mention that you don't even have a "mechanism" other than idle
speculation. Your mechanism might as well be magic pixie dust.
> Your original argument was that there is no interaction between
> electrostatic/magnetostatic fields and electromagnetic waves per se.
> This is clearly incorrect as it would imply that light would not
> interact with matter at all, i.e. we would have no refraction, Faraday
> rotation etc.
Your supposition is illogical. Interactions with *matter and charges*
-- not pure fields -- yield those effects. Thus your criticism is
irrelevant.
> > Instead, you posit some mysterious "fundamental" interaction between
> > electric fields and electromagnetic waves which has *just the right*
> > behavior [*]... but absolutely no substantiation in theory or
> > experiment. I'm sure that's great for you, but it's irrelevant to the
> > rest of the world.
>
> If your attitude is 'I don't care about what I don't know' then you
> shouldn't be working in science.
My attitude is, "I don't care about unsubstantiated theories."
> > [*] except when you define the electric field effect to be
> > wavelength dependent and wavelength independent at the same time.
> > Self-contradiction is not a good sign in any theory.
Note, no response.
> > > > Really? Let's look at the results.
> > > > McKellar (1941) derives a value of 2.3 K from CN, but with unknown
> > > > uncertainties (I do not have access to the primary source), but it
> > > > is fair to say that McKellar (1940) finds a range of 2.1-2.7 K.
> > > > Penzias & Wilson 1965, ApJ, 142, 419, found 3.5 +/- 0.5 K
> > > > via direct measurement.
> > > > The Thaddeus & Clauser paper you refer to (1966, PRL, 16, 819)
> > > > quotes values of 3.75 +/- 0.5 using CN.
> > > > Field & Hitchcock, 1966, ApJ, 146, 1, find 3.22+/-0.15 and 3.0+/-0.6 for
> > > > two different stars using CN.
> > > > Thaddeus (1972) ARA&A, points out that the weighted mean of all CN
> > > > measurements to that time was 2.78 +/- 0.10 K.
> > > > Roth, Meyer & Hawkins 1993, ApJL 413 L67, find 2.729 +/- 0.030 K,
> > > > using a compilation of sensitive CN measurements.
> > > >
> > > > What you are noting is fluctuations due to measurement uncertainties,
> > > > which for the early experiments are large. The weighted average of
> > > > the early results is consistent with the modern CN measurements, and
> > > > modern direct measurements. This is also noted by Ned Wright
> > > > (http://www.astro.ucla.edu/~wright/CMB.html), although it is plotted
> > > > against frequency, not publication date.
> > > >
> > > > So, NO one *cannot* derive any temperature that you want. Your claim
> > > > is erroneous.
> >
> > Note, no response.
Note, continued lack of response.
I note that you are reverting to the same dense argument you started
with. Your ignoring of the T(z=0) = 2.73 K data point is not tenable.
Not only is that number *VERY* well determined by direct measurement
of the CMB, it is also determined via absorption measurements very
similar to the high redshift ones (references already cited). Thus,
the low redshift end of the curve is very well tied, and your
criticism is erroneous.
But your original claim somehow regarded photoelectrons of kT = 10 eV
losing enough energy to reach kT = 0.01 eV. That claim is irrelevant.
The density of electrons in the plasma with energy kT = 10 eV is
negligible.
I note that you completely missed the point, which is that the
excitation temperature was used to set an initial upper limit to the
CMBR temperature -- not the final CMBR temperature estimate -- and
thus your criticism is irrelevant.
> >
> > Molaro et al. have an extensive description including equations (eq
> > 1&2) and figure (Fig 1)
> > Does it assume a Boltzmann distribution?
> > --> YES, to set an upper limit on the CMBR temperature
> > --> NO, after considering detailed balance of all processes
>
> Again, the use of an 'excitation temperature' to describe the
> population of the levels proves that they assume LTE conditions i.e. a
> Boltzmann distribution.
Again, you missed the point (see above).
> > Silva & Viegas contains detailed modeling, including excitation
> > rates of the relevant transitions due the CMBR at various
> > temperatures, and full detailed balance calculations
> > Does it assume a Boltzmann distribution? --> NO
>
> I quote from the paper (section 2 near Eq.(6)): 'The fine structure
> levels may also be directly populated by the CMBR. In that case one
> must add to the energy densities a contribution from a blackbody
> radiation field redshifted to a temperature T=T0*(1+z). .....**We
> caution however that this relation remains yet observationally
> unproven**'.
True, but consider that T = T0*(1+z) is just a convenient
parameterization of the temperature dependence of the various
excitation processe involved. One can think of z as simply a number
used to scale T0 (one could have used T0*exp(z), T0*(1+z)^2, etc just
as easily).. Since the temperature-vs-redshift relation is (1+z), it
is a convenient scaling. Thus, your criticism is irrelevant.
...
> http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ). This very much
> resembles the inconclusive result obtained by Srianand et al (
> http://www.plasmaphysics.org.uk/imgs/srianand.gif ) . In fact it is
> even worse as near about z=2, there are several data points that are
> mutually exclusive and could not possibly fit any curve.
...
Note that the plot you reproduced includes *excitation temperatures*
only, not the estimated CMBR temperatures. Thus, your criticism is
irrelevant.
...
> This is also further confirmed by
> certain inconsistencies in the paper:
> from Table 1 it follows that the excitation rate due to the CMBR into
> the second fine structure level is many orders of magnitudes smaller
> than that into the first (8 orders of magnitude for z=2). This should
> be directly reflected in the corresponding level population due to the
> CMBR. However, Fig.2 suggests that the population ratio is reduced by
> merely about one order of magnitude (with even for the second level,
> the contribution due to the CMBR exceeding that due to collisions).
I note that you neglected the 1 -> 2 transition (at wavelength 370 um),
which is significantly excited by the CMBR, especially for z > 1 (e.g.
see Molaro et al Figure 1). [*] Thus your criticism is erroneous.
[*] whereas the 0 -> 2 transition is a forbidden one.
> There is also a puzzling verbal inconsistency: the theory section
> suggests that the CMBR is taken explicitly into account for determining
> the level population (see the quote at the top of this paragraph), but
> then right at the bottom of paragraph 2.2 they say: 'The model
> presented here should allow the inclusion of excitation by the CMBR'.
> This suggests that they actually did not consider it consistently
> together with the other excitation mechanism, but merely added it by
> means of some ad-hoc assumptions associated with the observed level
> populations and the theoretical predictions for the other mechanisms.
Since the section of the paper you cited deals with the general
properties of the individual species, and not the detailed balance
equations applied to a particular observation, your criticism is
irrelevant.
Incidentally, Silva and Viegas (2002) is the exactly you complained
did not exist: It is a treatment of the physical effects relevant to
the atoms being measured.
...
> > Your claims continue to be erroneous and unsubstantiated.
> >
> > You also conveniently deleted several parts of the previous post.
> >
> > [ Smid: ]
> > > As far as I am aware, the SZ effect has not been confirmed in the Wien
> > > region of the spectrum as yet (where it should lead to an increase of
> > > the CMB intensity rather than a decrease as for the lower frequencies).
> >
> > [ Markwardt: ]
> > : Kudos to your awareness. However, the lack of experimental
> > : confirmation of all aspects of a theory does not negate the theory
> > : (and unlike the observed SZ decrement, the detection of an increment
> > : would be in a region of the EM spectrum which is extremely difficult
> > : to observe).
> >
> > I note no response.
I note a continued lack of response.
> >
> > [ Markwardt: ]
> > : But as noted above, and as you admit yourself, your "theory" is not a
> > : theory at all. It has no independent basis in experiment; is not
> > : borne out or connected to any other theory; it's just wishful
> > : thinking. Meanwhile, the theoretical physics underlying the SZ effect
> > : -- Comptonization -- is well tested and understood.
> >
> > I note a continued lack of response.
Once again, I note a continued lack of response.
You should try to substantiate your claims before issuing them.
> > Given your continual erroneous speculations and unsubstantiated
> > claims, it's not really worth my time to continue this thread.
>
> Just as well given the insubstantial nature of your arguments.
That is highly ironic, given that it is me that is provided extensive
citations which back up rebuttals to your off-hand remarks and ad hoc
unsubstantiated theories.
CM
Thomas Smid
> But wait, you simultaneously suggest that your "mechanism" does not
> have a wavelength dependence (see above), *AND* that it *DOES* have a
> wavelength dependence,
> "First of all, it is reasonable to assume that the redshift (as well
> as the angular deflection) is not only proportional to the electric
> field, but also to the wavelength as the potential difference
> between two wave crests is proportional to it."
> http://www.plasmaphysics.org.uk/research/lensing.htm
>
> I note that despite this inconsistency being brought to your attention
> multiple times, you continue to ignore it. As your theory is
> self-contradictory, it is irrelevant.
You should have quoted the other half of my argument as well:
"Furthermore, one has to take into account that the field gradient
(i.e. the finite size of the field region) should lead to a diffraction
effect which can be expected to result in a reduction of the
redshift/deflection i.e. in an inversely proportional dependence on
wavelength. Overall there should thus not be an wavelength dependence
(as observed)"
So I am not contradicting myself at all here. Whether the
wavelength-independence is actually due to these circumstances is a
different matter, but at the moment I can't see any other potentially
valid cause.
>
>
> Not to mention that you don't even have a "mechanism" other than idle
> speculation. Your mechanism might as well be magic pixie dust.
>
>
> > Your original argument was that there is no interaction between
> > electrostatic/magnetostatic fields and electromagnetic waves per se.
> > This is clearly incorrect as it would imply that light would not
> > interact with matter at all, i.e. we would have no refraction, Faraday
> > rotation etc.
>
> Your supposition is illogical. Interactions with *matter and charges*
> -- not pure fields -- yield those effects.
So what properties of matter result then in your opinion in refraction
and Faraday rotation of light? Maybe the mass? Or magic pixie dust (to
use the phrase coined by you)? I would rather suggest that it is
electric/magnetic fields (and only those).
>
>
> > > Instead, you posit some mysterious "fundamental" interaction between
> > > electric fields and electromagnetic waves which has *just the right*
> > > behavior [*]... but absolutely no substantiation in theory or
> > > experiment. I'm sure that's great for you, but it's irrelevant to the
> > > rest of the world.
> >
> > If your attitude is 'I don't care about what I don't know' then you
> > shouldn't be working in science.
>
> My attitude is, "I don't care about unsubstantiated theories."
'Unfamiliar' and 'unsubstantiated' seem to be two synonymous words for
you.
You still don't seem to be getting the point. The COBE measurement for
z=0 has nothing to do with the kind of data analysis use for the other
points. It is merely (illegitimately) used to constrain the latter such
that they indicate an increasing temperature with z. As such, the fine
structure measurements don't allow the conclusion of an increase of T
with z. The derived excitation temperature could as well be constant at
about 8K i.e. it could be unrelated to the CMBR altogether.
> > I don't know what you mean. Again, excitation of higher levels by
> > photoelectrons will necessarily increase the population of the lower
> > levels as the former are de-excited. This would thus directly affect
> > the strength of the absorption lines observed.
>
> But your original claim somehow regarded photoelectrons of kT = 10 eV
> losing enough energy to reach kT = 0.01 eV. That claim is irrelevant.
> The density of electrons in the plasma with energy kT = 10 eV is
> negligible.
It shouldn't be negligible. UV radiation leads to electrons being
primarily produced at energies 10-20 eV, and they can't lose much of
their kinetic energy in elastic collisions with neutrals and ions due
to their small mass. They'll recombine way before they have
thermalized.
> > I quote from the paper (section 2 near Eq.(6)): 'The fine structure
> > levels may also be directly populated by the CMBR. In that case one
> > must add to the energy densities a contribution from a blackbody
> > radiation field redshifted to a temperature T=T0*(1+z). .....**We
> > caution however that this relation remains yet observationally
> > unproven**'.
>
> True, but consider that T = T0*(1+z) is just a convenient
> parameterization of the temperature dependence of the various
> excitation processe involved. One can think of z as simply a number
> used to scale T0 (one could have used T0*exp(z), T0*(1+z)^2, etc just
> as easily).. Since the temperature-vs-redshift relation is (1+z), it
> is a convenient scaling.
It is convenient because the data are inconclusive in this respect. As
indicated above already in connection with the Srianand data
(http://www.plasmaphysics.org.uk/imgs/srianand.gif ) the fine structure
excitation could as well be completely independent of z.
> ...
> > http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ). This very much
> > resembles the inconclusive result obtained by Srianand et al (
> > http://www.plasmaphysics.org.uk/imgs/srianand.gif ) . In fact it is
> > even worse as near about z=2, there are several data points that are
> > mutually exclusive and could not possibly fit any curve.
> ...
>
> Note that the plot you reproduced includes *excitation temperatures*
> only, not the estimated CMBR temperatures.
The 'excitation temperatures' are obviously implied to be identical to
the CMBR temperatures here. After all, like Srianand et al., they also
try to 'fit' the data with a curve linearly increasing with z. Whereas
in the former case this was at least still a theoretical possibility,
here it is in fact ruled out by the data as several data points can not
be fitted at all by *any* systematic temperature dependence. This shows
that one should better forget about these measurements as an indicator
of the CMBR temperature.
>
> ...
> > This is also further confirmed by
> > certain inconsistencies in the paper:
> > from Table 1 it follows that the excitation rate due to the CMBR into
> > the second fine structure level is many orders of magnitudes smaller
> > than that into the first (8 orders of magnitude for z=2). This should
> > be directly reflected in the corresponding level population due to the
> > CMBR. However, Fig.2 suggests that the population ratio is reduced by
> > merely about one order of magnitude (with even for the second level,
> > the contribution due to the CMBR exceeding that due to collisions).
>
> I note that you neglected the 1 -> 2 transition (at wavelength 370 um),
> which is significantly excited by the CMBR, especially for z > 1 (e.g.
> see Molaro et al Figure 1).
So what is then the excitation rate due to the CMBR for the 1->2
transition? If it would be in any way significant, Silva and Viegas
should have listed it (contrary, to what you are saying, Molaro et al.
indicate by the way only the 0->1 and and 0->2 transitions as well).
>
> > There is also a puzzling verbal inconsistency: the theory section
> > suggests that the CMBR is taken explicitly into account for determining
> > the level population (see the quote at the top of this paragraph), but
> > then right at the bottom of paragraph 2.2 they say: 'The model
> > presented here should allow the inclusion of excitation by the CMBR'.
> > This suggests that they actually did not consider it consistently
> > together with the other excitation mechanism, but merely added it by
> > means of some ad-hoc assumptions associated with the observed level
> > populations and the theoretical predictions for the other mechanisms.
>
> Since the section of the paper you cited deals with the general
> properties of the individual species, and not the detailed balance
> equations applied to a particular observation, your criticism is
> irrelevant.
The section I cited from deals with the results of the calculations for
the excitation and population for the excited levels of C^0 . These
results show in detail the influence of the CMBR on the population
ratios. In this respect, it is completely puzzling why then they
finally say 'The model presented here should allow the inclusion of
excitation by the CMBR'.
> > > Given your continual erroneous speculations and unsubstantiated
> > > claims, it's not really worth my time to continue this thread.
> >
> > Just as well given the insubstantial nature of your arguments.
>
> That is highly ironic, given that it is me that is provided extensive
> citations which back up rebuttals to your off-hand remarks and ad hoc
> unsubstantiated theories.
The only way to make your case seems to be by pointing me to references
that are themselves unsubstantiated or flawed. You should at least read
them properly before bringing them into the discussion.
Thomas
Craig Markwardt
I note you conveniently deleted several sections of the previous post.
For example,
[ Markwardt: ]
: Precisely. All the well known electromagnetic interactions with
: matter are highly chromatic. Your suggested electric field
: "mechanism" is not chromatic, which also suggests that it is
: wrong.
I note no response.
"Thomas Smid" <thoma...@gmail.com> writes:
> Craig Markwardt wrote:
>
>
> > But wait, you simultaneously suggest that your "mechanism" does not
> > have a wavelength dependence (see above), *AND* that it *DOES* have a
> > wavelength dependence,
>
> > "First of all, it is reasonable to assume that the redshift (as well
> > as the angular deflection) is not only proportional to the electric
> > field, but also to the wavelength as the potential difference
> > between two wave crests is proportional to it."
> > http://www.plasmaphysics.org.uk/research/lensing.htm
> >
> > I note that despite this inconsistency being brought to your attention
> > multiple times, you continue to ignore it. As your theory is
> > self-contradictory, it is irrelevant.
>
> You should have quoted the other half of my argument as well:
> "Furthermore, one has to take into account that the field gradient
> (i.e. the finite size of the field region) should lead to a diffraction
> effect which can be expected to result in a reduction of the
> redshift/deflection i.e. in an inversely proportional dependence on
> wavelength. Overall there should thus not be an wavelength dependence
> (as observed)"
> So I am not contradicting myself at all here. Whether the
> wavelength-independence is actually due to these circumstances is a
> different matter, but at the moment I can't see any other potentially
> valid cause.
Hmmm. Unfortunately for you, diffraction -- as it is well known --
does not "bend" light, but rather creates an interference pattern,
i.e. a redistribution of the light into discrete diffraction maxima.
Such an effect is of course not observed in light bending around the sun.
But ignoring even that for the moment, the angles of diffraction
intensity maxima *increase* with wavelength, contrary to your
speculation. [*] I suppose at this stage you will appeal to some
hitherto unknown "fundamental" mechanism for that too?
[*] which is true for classic single slit diffraction, a*sin(theta) =
m*lambda, where theta is the angle of periodic intensity maxima, a is
the slit width, lambda is the wavelength, and m is the order. But it
is also true for diffraction through and around more complicated
apertures.
> > Not to mention that you don't even have a "mechanism" other than idle
> > speculation. Your mechanism might as well be magic pixie dust.
Note, no response.
> > > Your original argument was that there is no interaction between
> > > electrostatic/magnetostatic fields and electromagnetic waves per se.
> > > This is clearly incorrect as it would imply that light would not
> > > interact with matter at all, i.e. we would have no refraction, Faraday
> > > rotation etc.
> >
> > Your supposition is illogical. Interactions with *matter and charges*
> > -- not pure fields -- yield those effects.
>
> So what properties of matter result then in your opinion in refraction
> and Faraday rotation of light? Maybe the mass? Or magic pixie dust (to
> use the phrase coined by you)? I would rather suggest that it is
> electric/magnetic fields (and only those).
My "opinion" is irrelevant. Most optics textbooks have a serviceable
physically motivated and/or atomistic descriptions of refraction. I
have Hecht, *Optics*, which is quite nice. Faraday rotation is well
understood in terms of the response to an electromagnetic wave of free
electrons in a magnetic field (e.g.
http://farside.ph.utexas.edu/teaching/em/lectures/node101.html).
Also, these kinds of phenomena have been hashed out over the past
century or more, via theoretical and experimental exploration. Hardly
"pixie dust." I note that you could have consulted basic textbook
resources, but did not.
> > > > Instead, you posit some mysterious "fundamental" interaction between
> > > > electric fields and electromagnetic waves which has *just the right*
> > > > behavior [*]... but absolutely no substantiation in theory or
> > > > experiment. I'm sure that's great for you, but it's irrelevant to the
> > > > rest of the world.
> > >
> > > If your attitude is 'I don't care about what I don't know' then you
> > > shouldn't be working in science.
> >
> > My attitude is, "I don't care about unsubstantiated theories."
>
> 'Unfamiliar' and 'unsubstantiated' seem to be two synonymous words for
> you.
Well, if you mean that I am "unfamiliar" with any substantiation of
your speculation -- experimental, theoretical or otherwise -- that's true.
Typically, new scientific theories will need to be carefully compared
with previous theories, previous observations, specific (quantitative)
predictions made, etc. Your "theory" has none of that.
> points. ...
That criticism is irrelevant for two reasons. First, there is *no
requirement* that only experiments of the same type can be compared.
For example, GPS, satellite laser ranging, and VLBI are quite
different techniques, and yet they can be combined to form a uniform
picture of earth orientation.
Second, the local temperature of the CMBR has been measured using the
*same* type of technique as those at high redshift, to high precision
(Roth, Meyer & Hawkins 1993, ApJL 413 L67). In fact, this technique
was used (crudely) before microwave detectors measured the CMBR
temperature directly. Despite noting this numerous times, you
continue to ignore it.
> > > I don't know what you mean. Again, excitation of higher levels by
> > > photoelectrons will necessarily increase the population of the lower
> > > levels as the former are de-excited. This would thus directly affect
> > > the strength of the absorption lines observed.
> >
> > But your original claim somehow regarded photoelectrons of kT = 10 eV
> > losing enough energy to reach kT = 0.01 eV. That claim is irrelevant.
> > The density of electrons in the plasma with energy kT = 10 eV is
> > negligible.
>
> It shouldn't be negligible. UV radiation leads to electrons being
> primarily produced at energies 10-20 eV, and they can't lose much of
> their kinetic energy in elastic collisions with neutrals and ions due
> to their small mass. They'll recombine way before they have
> thermalized.
Your criticism is still irrelevant. The species observed are neutral
*ground-state* Carbon and once-ionized *ground-state* Carbon. There
are no lower levels that "photoelectrons" can "de-excite" into -- they
are in the ground state!
Yes, there is a galactic UV component which ionizes neutral
Carbon. That is what produces the Carbon ions being studied!
Here again you conveniently deleted a section of the previous post:
[ Smid: ]
> > > As I said, the excitation rates due to the CMB is not explicity
> > > calculated in these papers. They assume a Boltzmann distribution for
> > > the population of the fine structure levels and on the basis of this
> > > they derive an 'excitation temperature' from the observations. Then
> > > they estimate what contribution to this excitation temperature a number
> > > of other mechanisms make and conclude that the remainder must be due
> > > to the CMB. Nowhere is the proposed excitation due to the CMB actually
> > > theoretically discussed in any way.
[ Markwardt: ]
> > Really? Let's look.
> > Srianand et al. refer to Meyer et al 1986, ApJL 308, L37 for calculations
> > Does it assume a Boltzmann distribution?
> > --> YES, to set an upper limit on the CMBR temperature
> > --> NO, after considering detailed balance of all processes
[ Smid: ]
> The use of an 'excitation temperature' to describe the population of
> the levels proves that they assume LTE conditions i.e. a Boltzmann
> distribution.
[ Markwardt: ]
: I note that you completely missed the point, which is that the
: excitation temperature was used to set an initial upper limit to the
: CMBR temperature -- not the final CMBR temperature estimate -- and
: thus your criticism is irrelevant.
[ Markwardt: ]
> > Molaro et al. have an extensive description including equations (eq
> > 1&2) and figure (Fig 1)
> > Does it assume a Boltzmann distribution?
> > --> YES, to set an upper limit on the CMBR temperature
> > --> NO, after considering detailed balance of all processes
[ Smid: ]
> Again, the use of an 'excitation temperature' to describe the
> population of the levels proves that they assume LTE conditions i.e. a
> Boltzmann distribution.
[ Markwardt: ]
: Again, you missed the point (see above).
I note your continued lack of response.
> > > I quote from the paper (section 2 near Eq.(6)): 'The fine structure
> > > levels may also be directly populated by the CMBR. In that case one
> > > must add to the energy densities a contribution from a blackbody
> > > radiation field redshifted to a temperature T=T0*(1+z). .....**We
> > > caution however that this relation remains yet observationally
> > > unproven**'.
> >
> > True, but consider that T = T0*(1+z) is just a convenient
> > parameterization of the temperature dependence of the various
> > excitation processe involved. One can think of z as simply a number
> > used to scale T0 (one could have used T0*exp(z), T0*(1+z)^2, etc just
> > as easily).. Since the temperature-vs-redshift relation is (1+z), it
> > is a convenient scaling.
>
> It is convenient because the data are inconclusive in this respect.
This is a nonsensical claim. The authors could have just as easily
labeled their table with T = 2.73, 5.46, 8.19, 10.92, 13.65, 16.38 K.
T=T0*(1+z) is simply a convenient parameterization of temperature.
...
> > > http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ). This very much
> > > resembles the inconclusive result obtained by Srianand et al (
> > > http://www.plasmaphysics.org.uk/imgs/srianand.gif ) . In fact it is
> > > even worse as near about z=2, there are several data points that are
> > > mutually exclusive and could not possibly fit any curve.
> > ...
> >
> > Note that the plot you reproduced includes *excitation temperatures*
> > only, not the estimated CMBR temperatures.
>
> The 'excitation temperatures' are obviously implied to be identical to
> the CMBR temperatures here. ...
Are you having reading problems? From the Silva and Viegas paper,
"Inspection of Fig. 12 reveals that current measurements do not
require any extra ingredients to the standard model, as the totality
of the points lie above the linear temperature law. However, a
conclusive statement could only be made after correcting for local
excitation mechanisms, in order to convert the excitation
temperature upper limits to the actual temperature of the CMBR."
Note the last sentence... you are in error.
> ... After all, like Srianand et al., they also
> try to 'fit' the data with a curve linearly increasing with z.
And as before, you make the error of calling it a "fit" when it is
not.
> ... Whereas
> in the former case this was at least still a theoretical possibility,
> here it is in fact ruled out by the data as several data points can not
> be fitted at all by *any* systematic temperature dependence. This shows
> that one should better forget about these measurements as an indicator
> of the CMBR temperature.
Or that one should read the paper more carefully before making
unsubstantiated claims about it.
> > ...
> > > This is also further confirmed by
> > > certain inconsistencies in the paper:
> > > from Table 1 it follows that the excitation rate due to the CMBR into
> > > the second fine structure level is many orders of magnitudes smaller
> > > than that into the first (8 orders of magnitude for z=2). This should
> > > be directly reflected in the corresponding level population due to the
> > > CMBR. However, Fig.2 suggests that the population ratio is reduced by
> > > merely about one order of magnitude (with even for the second level,
> > > the contribution due to the CMBR exceeding that due to collisions).
> >
> > I note that you neglected the 1 -> 2 transition (at wavelength 370 um),
> > which is significantly excited by the CMBR, especially for z > 1 (e.g.
> > see Molaro et al Figure 1).
>
> So what is then the excitation rate due to the CMBR for the 1->2
> transition? If it would be in any way significant, Silva and Viegas
> should have listed it ...
It's not really relevant. It's not the responsibility of the authors
to think of every nitpicking thing you might come up with, especially
since the stimulated excitation rate is a simple function of the
transition probablity, statistical weights, and the radiation density.
Also, it's worth pointing out that neutral carbon has *not* been used
for CMBR temperature estimates. In any case, the excitation rate can
be calculated by their available "popratio" program (z=2, K12=3.87E-9 s^-1).
> ... (contrary, to what you are saying, Molaro et al.
> indicate by the way only the 0->1 and and 0->2 transitions as well).
True, but it does give a nice graphical representation that shows that
the 1->2 transition wavelength (370 um) falls neatly in a wavelength
interval which is stimulated by the CMBR at higher redshifts.
So once again, your criticism is a red herring.
> > > There is also a puzzling verbal inconsistency: the theory section
> > > suggests that the CMBR is taken explicitly into account for determining
> > > the level population (see the quote at the top of this paragraph), but
> > > then right at the bottom of paragraph 2.2 they say: 'The model
> > > presented here should allow the inclusion of excitation by the CMBR'.
> > > This suggests that they actually did not consider it consistently
> > > together with the other excitation mechanism, but merely added it by
> > > means of some ad-hoc assumptions associated with the observed level
> > > populations and the theoretical predictions for the other mechanisms.
> >
> > Since the section of the paper you cited deals with the general
> > properties of the individual species, and not the detailed balance
> > equations applied to a particular observation, your criticism is
> > irrelevant.
>
> The section I cited from deals with the results of the calculations for
> the excitation and population for the excited levels of C^0. These
> results show in detail the influence of the CMBR on the population
> ratios. In this respect, it is completely puzzling why then they
> finally say 'The model presented here should allow the inclusion of
> excitation by the CMBR'.
OK, it's puzzling to you. Big deal. Is that really all you can come
up with? I took it to mean: researchers that use the Silva & Viegas
model will be able to include CMBR excitation of neutral Carbon in
their analyses. And in any case, it is clear from their "popratio"
program that they did include the CMBR in the same consistent manner
as all the other terms. Thus, your criticism is a complete diversion.
I note continued deletion and lack of response to several sections of
the previous post. [ which I grow weary of reproducing every time. ]
> > > > Given your continual erroneous speculations and unsubstantiated
> > > > claims, it's not really worth my time to continue this thread.
> > >
> > > Just as well given the insubstantial nature of your arguments.
> >
> > That is highly ironic, given that it is me that is provided extensive
> > citations which back up rebuttals to your off-hand remarks and ad hoc
> > unsubstantiated theories.
>
> The only way to make your case seems to be by pointing me to references
> that are themselves unsubstantiated or flawed. You should at least read
> them properly before bringing them into the discussion.
I would suggest that *you* read the cited papers properly, since so
far, the "flaws" that you have pointed out have been red herrings.
Let's summarize, to date, since I'm getting weary of your continued
unsubstantiated claims and speculations:
* the claimed redshift "mechanism" is in fact a speculation, with no
basis in theory or observation, and in fact there is no detailed
"mechanism" at all.
* appeals to analogy with electric fields are in fact
counterproductive since electromagnetic interactions are highly
chromatic, whereas redshift is not. [ Further appeals to magnetic
fields are also completely unsubstantiated. ]
* secondary appeals to a counteracting diffraction effect is also
untenable, especially because it has the *opposite* wavelength
dependence than you supposed, not to mention the fact that
diffraction would produce discrete angular maxima, whereas
redshift and/or gravitational lensing does not.
Regarding high redshift CMBR temperature measurements:
* criticism of the T=0 measurement, when in fact it is the most well
determined temperature (via direct measurement, and via absorption
lines).
* when excitation temperatures are presented, you assume they are
CMBR temperature estimates when they are not.
* criticism of CMBR temperature estimates using the Boltzmann
distribution, when it was not used for the CMBR temperature
estimates.
* claiming T*(1+z) is a "fit" when it is not.
* some half-baked and/or nit-picking canards like: "photoelectrons,"
"excitation rates," and "puzzling statements."
CM
Thomas Smid
> I note you conveniently deleted several sections of the previous post.
How could I possibly delete sections of your posts? They are still
there for everybody to read if needed. There is no point in quoting the
complete previous posts in the thread again and again. I respond only
to those points I think are relevant and that I have not answered
before in my previous posts.
Again, you should pay more attention to what I am saying:
I assume that the diffraction *reduces* the redshift and bending of
light i,e, the effects are inversely proportional to the size of the
field region (given the same field strength). I adopted this hypothesis
on my page http://www.plasmaphysics.org.uk/research/lensing.htm because
on the basis of the field strengths alone, the redshift of the solar
spectral lines (as calculated from the galactic redshifts) comes out a
factor 1/7*10^8 too small. Now this factor is consistent with the ratio
of the scales of the intergalactic plasma microfield (1 m) and of the
solar electric field ( 7*10^8 m = radius of the sun).
Diffraction is really the only way I can think of to bring in the
sizes of the interaction regions here. The diffraction as such is of
course insignificant as the scale of the field regions is in any case
much larger than the wavelength, but it can be assumed (or at least
speculated) that it will inversely effect the redshift/bending effect.
Now this diffraction related dependence would of course also mean that
the effects become wavelength-dependent. This is why I have
additionally assumed the redshift/bending for a constant field to be
proportional to wavelength, hence cancelling out the
wavelength-dependence due to diffraction related effect.
> > Thomas Smid wrote:
> > So what properties of matter result then in your opinion in refraction
> > and Faraday rotation of light? Maybe the mass? Or magic pixie dust (to
> > use the phrase coined by you)? I would rather suggest that it is
> > electric/magnetic fields (and only those).
>
> My "opinion" is irrelevant. Most optics textbooks have a serviceable
> physically motivated and/or atomistic descriptions of refraction. I
> have Hecht, *Optics*, which is quite nice. Faraday rotation is well
> understood in terms of the response to an electromagnetic wave of free
> electrons in a magnetic field (e.g.
> http://farside.ph.utexas.edu/teaching/em/lectures/node101.html).
> Also, these kinds of phenomena have been hashed out over the past
> century or more, via theoretical and experimental exploration. Hardly
> "pixie dust." I note that you could have consulted basic textbook
> resources, but did not.
Obviously, current theoretical models are unable to deal with the
effect I am suggesting. On the other hand, they are therefore also
unable to rule it out.
I have referred to refraction and Faraday rotation in this context only
as possibly related phenomena. Present theoretical models may be
appropriate to deal with these, but not with the suggested
redshift/bending effect in electric fields. It could turn out for
instance that the speed of light does in fact fundamentally depend on
the electric field rather than on the refractive index (which is only a
macroscopic physical quantity). However, at this stage there is really
no need to try to develop the details of an appropriate underlying
theory. It is more important to first try to experimentally or
observationally verify the effect as such.
> Typically, new scientific theories will need to be carefully compared
> with previous theories, previous observations, specific (quantitative)
> predictions made, etc. Your "theory" has none of that.
You have so far neither pointed out any theoretical inconsistency in my
theory, nor any observational evidence which would invalidate it.
> > Thomas Smid wrote:
> > You still don't seem to be getting the point. The COBE measurement for
> > z=0 has nothing to do with the kind of data analysis use for the other
> > points. ...
>
> That criticism is irrelevant for two reasons. First, there is *no
> requirement* that only experiments of the same type can be compared.
> For example, GPS, satellite laser ranging, and VLBI are quite
> different techniques, and yet they can be combined to form a uniform
> picture of earth orientation.
They *can* be combined, but they don't have to. On the other hand, the
direct COBE measurement of the CMBR is used to constrain the
'excitation temperatures' of atoms in extragalactic regions such as to
suggest that the latter are consistent with a linear increase of the
CMB temperature. Taking one data point away from a data sample should
not completely invalidate the conclusions, but it does if one leaves
out the point at z=0 in the results of Srianand et al. and Silva and
Viegas (see http://www.plasmaphysics.org.uk/imgs/srianand.gif and
http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ). In the latter
case, as mentioned already, it is obvious from the inconsistent data
points near z=2 that the 'excitation temperature' has in fact little
or nothing to do with the CMBR at all, and thus it can not be used to
conclusively derive the z-dependence of the CMB.
> Second, the local temperature of the CMBR has been measured using the
> *same* type of technique as those at high redshift, to high precision
> (Roth, Meyer & Hawkins 1993, ApJL 413 L67).
Just another example of your incorrect and misleading citations: this
paper deals with the analysis of CN-lines but not Carbon. Note also
that according to this analysis the 'excitation temperature' agrees
with the CMB temperature to within less than 0.1 K, which is completely
inconsistent with the results based on the Carbon measurements
discussed by the other authors..
> > > The density of electrons in the plasma with energy kT = 10 eV is
> > > negligible.
> >
> > It shouldn't be negligible. UV radiation leads to electrons being
> > primarily produced at energies 10-20 eV, and they can't lose much of
> > their kinetic energy in elastic collisions with neutrals and ions due
> > to their small mass. They'll recombine way before they have
> > thermalized.
>
> Your criticism is still irrelevant. The species observed are neutral
> *ground-state* Carbon and once-ionized *ground-state* Carbon. There
> are no lower levels that "photoelectrons" can "de-excite" into -- they
> are in the ground state!
But the whole point of the measurements is to determine the population
of the *excited* fine structure levels i.e. of those Carbon atoms *not*
in the ground state. Now these can be populated not only from the
ground state, but also from even higher levels. However, the latter can
only be populated from the ground state by means of collisions with
photoelectrons of sufficient energy.
> > Thomas Smid wrote:
> > The 'excitation temperatures' are obviously implied to be identical to
> > the CMBR temperatures here. ...
>
> Are you having reading problems? From the Silva and Viegas paper,
> "Inspection of Fig. 12 reveals that current measurements do not
> require any extra ingredients to the standard model, as the totality
> of the points lie above the linear temperature law. However, a
> conclusive statement could only be made after correcting for local
> excitation mechanisms, in order to convert the excitation
> temperature upper limits to the actual temperature of the CMBR."
I told you already you shouldn't take everything necessarily for
granted you are reading. This statement can only be taken as a bit of a
joke by the authors because obviously, looking at the data, *no*
theoretical model would require modification as the data points show no
systematic behaviour at all. In fact, their statement 'the totality of
the points lie above the linear temperature law' is untrue as the data
points representing merely upper limits could also lie below that.
Basically, what they are saying here is that they have to get back to
the drawing board in order to theoretically model the data. Contrary to
what they are suggesting in the quoted paragraph, they considered all
the possible excitation mechanism in their program (and from the plots
of the level populations it is apparent that the CMBR is by far the
dominant factor in their excitation model for the chosen lines). If
they still get inconclusive results, this very much indicates that
there is something seriously wrong with their theoretical assumptions.
In any case, it should be clear that these measurements are by no means
proof of an increasing CMBR temperature with z (as you have been
suggesting).
> > Thomas Smid wrote:
> > So what is then the excitation rate due to the CMBR for the 1->2
> > transition? If it would be in any way significant, Silva and Viegas
> > should have listed it ...
>
> It's not really relevant. It's not the responsibility of the authors
> to think of every nitpicking thing you might come up with, especially
> since the stimulated excitation rate is a simple function of the
> transition probablity, statistical weights, and the radiation density.
> Also, it's worth pointing out that neutral carbon has *not* been used
> for CMBR temperature estimates. In any case, the excitation rate can
> be calculated by their available "popratio" program (z=2, K12=3.87E-9 s^-1).
I don't know why you are saying that neutral carbon was not used for
the CMBR temparature estimates. The plots in Sect.2.2 of the paper show
something else. In fact, most of the data points in their temperature
vs. z plot that are not just upper limits are due to neutral carbon
(filled circles).
So an excitation rate of K12=3.87E-9 s^-1 should not only be relevant
but crucial as K02 is so small. It seems therefore non-sensical to
include the latter in their Table 1 but not K12. But given the complete
failure to model the observations theoretically, it really doesn't make
a difference anyway. In this respect, it appears somewhat ironic that
they offer their POPRATIO program as a download.
Thomas
Craig Markwardt
"Thomas Smid" <thoma...@gmail.com> writes:
> Craig Markwardt wrote:
>
> > I note you conveniently deleted several sections of the previous post.
>
> How could I possibly delete sections of your posts? They are still
> there for everybody to read if needed. There is no point in quoting the
> complete previous posts in the thread again and again. I respond only
> to those points I think are relevant and that I have not answered
> before in my previous posts.
However, there are contested and relevant portions of the thread which
you conveniently deleted. For example,
[ Markwardt: ]
: Precisely. All the well known electromagnetic interactions with
: matter are highly chromatic. Your suggested electric field
: "mechanism" is not chromatic, which also suggests that it is
: wrong.
You conveniently deleted it because you don't have a response to it.
While you argue by analogy to "electric fields," in fact your "theory"
has nothing to do with the known properties of electric fields.
...
Perhaps *you* should pay more attention to what you are saying. As
already noted, the angle of measured diffraction maxima *increases*
with wavelength, not decrease as you erroneously supposed. Not to
mention the fact that diffraction does *not* "bend" light, as also
noted above. Thus, your "adoption" of the diffraction "hypothesis" is
irrelevant, and your theory is erroneous.
...
> > > Thomas Smid wrote:
> > > So what properties of matter result then in your opinion in refraction
> > > and Faraday rotation of light? Maybe the mass? Or magic pixie dust (to
> > > use the phrase coined by you)? I would rather suggest that it is
> > > electric/magnetic fields (and only those).
> >
> > My "opinion" is irrelevant. Most optics textbooks have a serviceable
> > physically motivated and/or atomistic descriptions of refraction. I
> > have Hecht, *Optics*, which is quite nice. Faraday rotation is well
> > understood in terms of the response to an electromagnetic wave of free
> > electrons in a magnetic field (e.g.
> > http://farside.ph.utexas.edu/teaching/em/lectures/node101.html).
> > Also, these kinds of phenomena have been hashed out over the past
> > century or more, via theoretical and experimental exploration. Hardly
> > "pixie dust." I note that you could have consulted basic textbook
> > resources, but did not.
>
> Obviously, current theoretical models are unable to deal with the
> effect I am suggesting. On the other hand, they are therefore also
> unable to rule it out.
Actually, current theoretical models have no place for the "effect"
you are suggesting. It's actually quite simple: by the linearity
principle of Maxwell's equations, electromagnetic waves in a vacuum do
not interact with static electric fields. Thus, whatever "effect" you
are describing is not an electric field as it is classically known.
It might as well be magic pixie dust.
> I have referred to refraction and Faraday rotation in this context only
> as possibly related phenomena. Present theoretical models may be
> appropriate to deal with these, but not with the suggested
> redshift/bending effect in electric fields. It could turn out for
> instance that the speed of light does in fact fundamentally depend on
> the electric field rather than on the refractive index (which is only a
> macroscopic physical quantity). However, at this stage there is really
> no need to try to develop the details of an appropriate underlying
> theory. It is more important to first try to experimentally or
> observationally verify the effect as such.
Without a detailed theory -- or for that matter even a vague theory --
there's really nothing for you to "verify." I'm sure that's pretty
convenient for you.
> > Typically, new scientific theories will need to be carefully compared
> > with previous theories, previous observations, specific (quantitative)
> > predictions made, etc. Your "theory" has none of that.
>
> You have so far neither pointed out any theoretical inconsistency in my
> theory, nor any observational evidence which would invalidate it.
There is the small matter that your supposed "diffraction" has nothing
to do with how normal diffraction behaves. Or, that your supposed
"electric fields" have nothing to do with how well understood electric
and magnetic fields behave. But you're right, it's hard to argue
against magic pixie dust.
> > > Thomas Smid wrote:
> > > You still don't seem to be getting the point. The COBE measurement for
> > > z=0 has nothing to do with the kind of data analysis use for the other
> > > points. ...
> >
> > That criticism is irrelevant for two reasons. First, there is *no
> > requirement* that only experiments of the same type can be compared.
> > For example, GPS, satellite laser ranging, and VLBI are quite
> > different techniques, and yet they can be combined to form a uniform
> > picture of earth orientation.
>
> They *can* be combined, but they don't have to. On the other hand, the
> direct COBE measurement of the CMBR is used to constrain the
> 'excitation temperatures' of atoms in extragalactic regions such as to
> suggest that the latter are consistent with a linear increase of the
> CMB temperature. Taking one data point away from a data sample should
> not completely invalidate the conclusions, but it does if one leaves
> out the point at z=0 in the results of Srianand et al. and Silva and
> Viegas (see http://www.plasmaphysics.org.uk/imgs/srianand.gif and
> http://www.plasmaphysics.org.uk/imgs/silva-viegas.gif ).
Your "take one point away" argument is non-sensical. In fact, the
local CMBR temperature is extremely well measured by several
techniques -- direct and indirect -- and by multiple observers (as
already mentioned in a portion of the post which you conveniently
trimmed). Even if one were to discard one of those points -- even
discarding the most precise of those points -- one would still be left
with a local CMBR temperature T = 2.73 K, with an uncertainty of less
than ~1%. Thus, your claim is truly irrelevant.
And the plots you refer to are *not* fits, but rather a simple overlay
of the fixed function T = 2.73 (1 + z) K. The hypothesis being tested
was, are the observations -- either CMBR temperature estimates, or
excitation temperatures -- consistent with that function. And the
answer was, yes.
> ... In the latter
> case, as mentioned already, it is obvious from the inconsistent data
> points near z=2 that the 'excitation temperature' has in fact little
> or nothing to do with the CMBR at all, and thus it can not be used to
> conclusively derive the z-dependence of the CMB.
Since the Viegas et al paper never claimed to conclusively derive the
redshift dependence of the CMBR temperature, your statement is
irrelevant. Even so, the excitation temperatures plotted are
certainly consistent with T = 2.73 (1+z) K, in that they are not
smaller than that function, nor tens or hundreds of degrees larger.
And it is worth noting that other referred-to papers -- which you
deleted -- *do* estimate the CMBR temperature (as opposed to simply
excitation temperatures), which are consistent with the redshift
relation.
> > Second, the local temperature of the CMBR has been measured using the
> > *same* type of technique as those at high redshift, to high precision
> > (Roth, Meyer & Hawkins 1993, ApJL 413 L67).
>
> Just another example of your incorrect and misleading citations: this
> paper deals with the analysis of CN-lines but not Carbon.
Actually, it's hardly misleading. I had already mentioned several
times -- but you deleted -- that these observations were based on the
CN molecule.
*HOWEVER*, the measurement *technique* is the same, as I claimed.
Both involve measuring absorption spectra of species with transitions
that can be excited by the CMBR. The physics of absorption doesn't
magically change when a different species is involved.
> ... Note also
> that according to this analysis the 'excitation temperature' agrees
> with the CMB temperature to within less than 0.1 K, which is completely
> inconsistent with the results based on the Carbon measurements
> discussed by the other authors..
Huh? Apparently you are having reading problems, since the quoted
reference was for the *local* CMBR, which was the point after all.
> > > > The density of electrons in the plasma with energy kT = 10 eV is
> > > > negligible.
> > >
> > > It shouldn't be negligible. UV radiation leads to electrons being
> > > primarily produced at energies 10-20 eV, and they can't lose much of
> > > their kinetic energy in elastic collisions with neutrals and ions due
> > > to their small mass. They'll recombine way before they have
> > > thermalized.
> >
> > Your criticism is still irrelevant. The species observed are neutral
> > *ground-state* Carbon and once-ionized *ground-state* Carbon. There
> > are no lower levels that "photoelectrons" can "de-excite" into -- they
> > are in the ground state!
>
> But the whole point of the measurements is to determine the population
> of the *excited* fine structure levels i.e. of those Carbon atoms *not*
> in the ground state. Now these can be populated not only from the
> ground state, but also from even higher levels. However, the latter can
> only be populated from the ground state by means of collisions with
> photoelectrons of sufficient energy.
Perhaps it is time for you to review atomic physics. The atoms/ions
are in the *electronic* ground state. The fine structure levels do
not involve electronic transitions, but rather spin transitions.
Once again, since the plot shows excitation temperature vs. z -- as
described by the authors -- your criticism is irrelevant.
What you are not getting is that the Silva & Viegas result is showing
*excitation temperature* vs. redshift. As there are other means of
excitation besides the CMBR, the determination of an excitation
temperature alone only sets an upper limit to the CMBR temperature
(and, as pointed out by Silva & Viegas., some of the excitation
temperatures themselves have only an upper limit). *HOWEVER*, none of
those upper limits is inconsistent with the T=2.73(1+z) K relation.
Furthermore, using the excitation temperatures alone, one can rule out
alternative models like T = 2.73 (1+z)^n where n>=2.
The joke is that you are still not getting the difference between
excitation temperature and CMBR temperature estimate. It relates
*exactly* to the portion of the previous post which you keep deleting
without responding to:
===
===
> > > Thomas Smid wrote:
> > > So what is then the excitation rate due to the CMBR for the 1->2
> > > transition? If it would be in any way significant, Silva and Viegas
> > > should have listed it ...
> >
> > It's not really relevant. It's not the responsibility of the authors
> > to think of every nitpicking thing you might come up with, especially
> > since the stimulated excitation rate is a simple function of the
> > transition probablity, statistical weights, and the radiation density.
> > Also, it's worth pointing out that neutral carbon has *not* been used
> > for CMBR temperature estimates. In any case, the excitation rate can
> > be calculated by their available "popratio" program (z=2, K12=3.87E-9 s^-1).
>
> I don't know why you are saying that neutral carbon was not used for
> the CMBR temparature estimates. The plots in Sect.2.2 of the paper show
> something else. ...
Since sect 2.2 of Silva & Viegas doesn't show any CMBR temperature
estimates, your claim is erroneous.
> ... In fact, most of the data points in their temperature
> vs. z plot that are not just upper limits are due to neutral carbon
> (filled circles).
Since Fig 12 of Silva & Viegas shows only one CMBR temperature
estimate (not the filled circles), again your claim is erroneous.
> So an excitation rate of K12=3.87E-9 s^-1 should not only be relevant
> but crucial as K02 is so small. It seems therefore non-sensical to
> include the latter in their Table 1 but not K12. But given the complete
> failure to model the observations theoretically, it really doesn't make
> a difference anyway. In this respect, it appears somewhat ironic that
> they offer their POPRATIO program as a download.
Do you mean that it's ironic that the authors provided a detailed
model including many physical effects, and were considerate enough to
provide the source code, but you did not do any of these things? Or
that, despite many corrections, you *still* don't get the difference
between excitation temperature and CMBR temperature estimate? Or that
you are nit-picking over a K12 constant which doesn't even change any
of the results?
Yes, those are pretty ironic things.
CM