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Does Dark energy exist?
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jacob navia
Apr 25, 2012, 1:12:31 AM4/25/12
to
Well, reading this blog at:
http://www.scilogs.eu/en/blog/the-dark-matter-crisis/2012-03-31/question-c.iii-fundamental-theoretical-problems
I stumbled upon this interesting paragraph:
(DE=Dark Energy)
<quote>
Indeed, DE may not even exist, resulting from integrating a supernova
(SN) Ia photon's path across the universe without correctly adding the
non-linear general-relativistic sequence of time delays and spatial
contractions as the photon traverses through the inhomogeneous matter
distribution between the SN Ia and the observer. An observer, who does
the calculation or averaging along the photon's path wrongly would
indeed deduce falsly that the universe is larger than it ought to be,
thus wrongly deducing the effect of an acceleration driven by DE. This
has been shown to be quite possibly the case by Wiltshire (2007).
<end quote>
Very interesting. But what did Mr Wiltshire said in 2007?
http://arxiv.org/abs/0709.0732
<quote of the abstract>
The exact solution of a two-scale Buchert average of the Einstein
equations is derived for an inhomogeneous universe which represents a
close approximation to the observed universe. The two scales represent
voids, and the bubble walls surrounding them within which clusters of
galaxies are located. As described elsewhere [gr-qc/0702082], apparent
cosmic acceleration can be recognised as a consequence of quasilocal
gravitational energy gradients between observers in bound systems and
the volume average position in freely expanding space. With this
interpretation, the new solution presented here replaces the Friedmann
solutions, in representing the average evolution of a matter-dominated
universe without exotic dark energy, while being observationally viable.
<end quote>
Obviously this is WAY beyond the powers of my little brain... For
starters, what can this "Buchert average" mean?
A Google search led me to the page of Thomas Buchert, that is an
astronomer at Lyon's University that has written many papers in
cosmology, and a very interesting book about "alternatives to the Big
Bang theories" that I will buy tomorrow. But there is nothing evident
about this "average" in there.
Has anyone here an idea of what that can be? Actually, (if I understand
anything), some people are saying that the photon path goes through
voids and clusters of galaxies what should mean that those matter
concentrations provoke delays/accelerations that we don't correctly
integrate, so that we interpret this changes as a signal that the
universe is bigger than it really is, falsely deducing an accelerating
expansion.
I never liked that expanding expansion idea of "dark" energy, mainly
because goes against what I learned when I was a kid at the physics
class: conservation of energy. But that is a reaction of an uninformed
layman, so I am happy that some professionals have also serious doubts
about the whole concept. I would like to understand why, but the papers
are so full of technical terms that it seems hopeless.
http://www.scilogs.eu/en/blog/the-dark-matter-crisis/2012-03-31/question-c.iii-fundamental-theoretical-problems
I stumbled upon this interesting paragraph:
(DE=Dark Energy)
<quote>
Indeed, DE may not even exist, resulting from integrating a supernova
(SN) Ia photon's path across the universe without correctly adding the
non-linear general-relativistic sequence of time delays and spatial
contractions as the photon traverses through the inhomogeneous matter
distribution between the SN Ia and the observer. An observer, who does
the calculation or averaging along the photon's path wrongly would
indeed deduce falsly that the universe is larger than it ought to be,
thus wrongly deducing the effect of an acceleration driven by DE. This
has been shown to be quite possibly the case by Wiltshire (2007).
<end quote>
Very interesting. But what did Mr Wiltshire said in 2007?
http://arxiv.org/abs/0709.0732
<quote of the abstract>
The exact solution of a two-scale Buchert average of the Einstein
equations is derived for an inhomogeneous universe which represents a
close approximation to the observed universe. The two scales represent
voids, and the bubble walls surrounding them within which clusters of
galaxies are located. As described elsewhere [gr-qc/0702082], apparent
cosmic acceleration can be recognised as a consequence of quasilocal
gravitational energy gradients between observers in bound systems and
the volume average position in freely expanding space. With this
interpretation, the new solution presented here replaces the Friedmann
solutions, in representing the average evolution of a matter-dominated
universe without exotic dark energy, while being observationally viable.
<end quote>
Obviously this is WAY beyond the powers of my little brain... For
starters, what can this "Buchert average" mean?
A Google search led me to the page of Thomas Buchert, that is an
astronomer at Lyon's University that has written many papers in
cosmology, and a very interesting book about "alternatives to the Big
Bang theories" that I will buy tomorrow. But there is nothing evident
about this "average" in there.
Has anyone here an idea of what that can be? Actually, (if I understand
anything), some people are saying that the photon path goes through
voids and clusters of galaxies what should mean that those matter
concentrations provoke delays/accelerations that we don't correctly
integrate, so that we interpret this changes as a signal that the
universe is bigger than it really is, falsely deducing an accelerating
expansion.
I never liked that expanding expansion idea of "dark" energy, mainly
because goes against what I learned when I was a kid at the physics
class: conservation of energy. But that is a reaction of an uninformed
layman, so I am happy that some professionals have also serious doubts
about the whole concept. I would like to understand why, but the papers
are so full of technical terms that it seems hopeless.
Phillip Helbig---undress to reply
Apr 25, 2012, 5:54:26 AM4/25/12
to
In article <mt2.0-24288...@hydra.herts.ac.uk>, jacob navia
look at the extent to which approximations usually used in cosmology
correspond to explicit integration along the path of the light ray.
Conclusion: the approximations are OK. I could dig out some references,
but since you seem to be able to dig out relatively obscure references,
I'll leave it as an exercise to find these. A few hints: Stockholm,
Holz&Wald.
> The exact solution of a two-scale Buchert average of the Einstein
> equations is derived for an inhomogeneous universe which represents a
> close approximation to the observed universe. The two scales represent
> voids, and the bubble walls surrounding them within which clusters of
> galaxies are located. As described elsewhere [gr-qc/0702082], apparent
> cosmic acceleration can be recognised as a consequence of quasilocal
> gravitational energy gradients between observers in bound systems and
> the volume average position in freely expanding space. With this
> interpretation, the new solution presented here replaces the Friedmann
> solutions, in representing the average evolution of a matter-dominated
> universe without exotic dark energy, while being observationally viable.
Rocky Kolb also tried something similar. These ideas are well known,
but they are contrived.
> Obviously this is WAY beyond the powers of my little brain... For
> starters, what can this "Buchert average" mean?
Thomas Buchert is quite well known in cosmological circles and for a
long time has been working on something called the averaging problem, as
has, for example, George Ellis. We know from GR the equations which
describe a homogeneous and isotropic universe. However, the real
universe is not completely homogeneous and isotropic. If it is "almost"
homogeneous and isotropic, does the Friedmann-Lemaître equation "almost"
describe our universe? And what does "almost" mean? This is the
averaging problem.
> A Google search led me to the page of Thomas Buchert, that is an
> astronomer at Lyon's University that has written many papers in
> cosmology, and a very interesting book about "alternatives to the Big
> Bang theories" that I will buy tomorrow. But there is nothing evident
> about this "average" in there.
>
> Has anyone here an idea of what that can be?
See above.
> Actually, (if I understand
> anything), some people are saying that the photon path goes through
> voids and clusters of galaxies what should mean that those matter
> concentrations provoke delays/accelerations that we don't correctly
> integrate, so that we interpret this changes as a signal that the
> universe is bigger than it really is, falsely deducing an accelerating
> expansion.
None of this is new. Rocky Kolb and Thomas Buchert are very well known
cosmologists. I've seen them both many times and even had dinner with
Buchert once. People know about their ideas. They are discussed.
There is no dictatorship of dark matter. There is no dictatorship of
dark energy. It's just that, on balance, most people think that dark
matter and dark energy are the best explanations. It is a healthy
debate.
Sometimes such discussion "one paper proves dark matter does not exist
and astronomers have been deluded" reminds me of the
creationist/evolutionist discussion in backward countries such as the
USA and Turkey. Creationists seize on a minor point of debate WITHIN
the field of evolution and Fox News reports it as proving that evolution
didn't happen.
<ja...@spamsink.net> writes:
> Indeed, DE may not even exist, resulting from integrating a supernova
> (SN) Ia photon's path across the universe without correctly adding the
> non-linear general-relativistic sequence of time delays and spatial
> contractions as the photon traverses through the inhomogeneous matter
> distribution between the SN Ia and the observer. An observer, who does
> the calculation or averaging along the photon's path wrongly would
> indeed deduce falsly that the universe is larger than it ought to be,
> thus wrongly deducing the effect of an acceleration driven by DE. This
> has been shown to be quite possibly the case by Wiltshire (2007).
> <end quote>
A brief search of the literature will find a few papers which explicitly
> Indeed, DE may not even exist, resulting from integrating a supernova
> (SN) Ia photon's path across the universe without correctly adding the
> non-linear general-relativistic sequence of time delays and spatial
> contractions as the photon traverses through the inhomogeneous matter
> distribution between the SN Ia and the observer. An observer, who does
> the calculation or averaging along the photon's path wrongly would
> indeed deduce falsly that the universe is larger than it ought to be,
> thus wrongly deducing the effect of an acceleration driven by DE. This
> has been shown to be quite possibly the case by Wiltshire (2007).
> <end quote>
look at the extent to which approximations usually used in cosmology
correspond to explicit integration along the path of the light ray.
Conclusion: the approximations are OK. I could dig out some references,
but since you seem to be able to dig out relatively obscure references,
I'll leave it as an exercise to find these. A few hints: Stockholm,
Holz&Wald.
> The exact solution of a two-scale Buchert average of the Einstein
> equations is derived for an inhomogeneous universe which represents a
> close approximation to the observed universe. The two scales represent
> voids, and the bubble walls surrounding them within which clusters of
> galaxies are located. As described elsewhere [gr-qc/0702082], apparent
> cosmic acceleration can be recognised as a consequence of quasilocal
> gravitational energy gradients between observers in bound systems and
> the volume average position in freely expanding space. With this
> interpretation, the new solution presented here replaces the Friedmann
> solutions, in representing the average evolution of a matter-dominated
> universe without exotic dark energy, while being observationally viable.
but they are contrived.
> Obviously this is WAY beyond the powers of my little brain... For
> starters, what can this "Buchert average" mean?
long time has been working on something called the averaging problem, as
has, for example, George Ellis. We know from GR the equations which
describe a homogeneous and isotropic universe. However, the real
universe is not completely homogeneous and isotropic. If it is "almost"
homogeneous and isotropic, does the Friedmann-Lemaître equation "almost"
describe our universe? And what does "almost" mean? This is the
averaging problem.
> A Google search led me to the page of Thomas Buchert, that is an
> astronomer at Lyon's University that has written many papers in
> cosmology, and a very interesting book about "alternatives to the Big
> Bang theories" that I will buy tomorrow. But there is nothing evident
> about this "average" in there.
>
> Has anyone here an idea of what that can be?
> Actually, (if I understand
> anything), some people are saying that the photon path goes through
> voids and clusters of galaxies what should mean that those matter
> concentrations provoke delays/accelerations that we don't correctly
> integrate, so that we interpret this changes as a signal that the
> universe is bigger than it really is, falsely deducing an accelerating
> expansion.
cosmologists. I've seen them both many times and even had dinner with
Buchert once. People know about their ideas. They are discussed.
There is no dictatorship of dark matter. There is no dictatorship of
dark energy. It's just that, on balance, most people think that dark
matter and dark energy are the best explanations. It is a healthy
debate.
Sometimes such discussion "one paper proves dark matter does not exist
and astronomers have been deluded" reminds me of the
creationist/evolutionist discussion in backward countries such as the
USA and Turkey. Creationists seize on a minor point of debate WITHIN
the field of evolution and Fox News reports it as proving that evolution
didn't happen.
Richard D. Saam
Apr 25, 2012, 11:50:08 AM4/25/12
to
has the impact of a conceptual universal viscosity on expansion rate
been addressed.
Viscosity is momentum(p) transferred per area(A).
Assume that the universe density ~H^2/G in units of mass/volume
as is currently accepted.
Without assuming any particular physical character
to this universe density other than a related viscosity p/A
then all objects (stars, galaxies, dark matter etc) in this universe
would be slowing down relative to this universe medium.
This effect would be more pronounced with distance
such that the interpretation
of the universe accelerated expansion (dark energy)
could be interpreted as local parts of the universe decelerated slowing
relative to distant parts of the universe
all of this happening in an overall linear expanding universe.
> Sometimes such discussion "one paper proves dark matter does not exist
> and astronomers have been deluded" reminds me of the
> creationist/evolutionist discussion in backward countries such as the
> USA and Turkey.
enlightened country. Past experience has shown such generalized
attitudes as not productive.
Richard D Saam
Eric Flesch
Apr 26, 2012, 4:25:38 AM4/26/12
to
On Wed, 25 Apr 12, jacob navia <ja...@spamsink.net> wrote:
>... so that we interpret this changes as a signal that the
shells of space are larger than 4piR, so everything at R looks smaller
and farther away compared with flat space -- looking like
"accelerating expansion".
>... so that we interpret this changes as a signal that the
>universe is bigger than it really is, falsely deducing an accelerating
>expansion.
Hyperbolic space, i.e. negatively curved, does this simply: the
>expansion.
shells of space are larger than 4piR, so everything at R looks smaller
and farther away compared with flat space -- looking like
"accelerating expansion".
Phillip Helbig---undress to reply
Apr 26, 2012, 7:05:48 AM4/26/12
to
In article <mt2.0-12093...@hydra.herts.ac.uk>, "Richard D. Saam"
distance) since anything else would destroy homogeneity. With time, the
constant of proportionality can change. In order to test your
hypothesis, you need to specify it mathematically in a form suitable for
comparison with observations.
<rds...@att.net> writes:
> could be interpreted as local parts of the universe decelerated slowing
> relative to distant parts of the universe
> all of this happening in an overall linear expanding universe.
At any one time, the expansion is linear (velocity proportional to
> could be interpreted as local parts of the universe decelerated slowing
> relative to distant parts of the universe
> all of this happening in an overall linear expanding universe.
distance) since anything else would destroy homogeneity. With time, the
constant of proportionality can change. In order to test your
hypothesis, you need to specify it mathematically in a form suitable for
comparison with observations.
jacob navia
Apr 26, 2012, 7:09:46 AM4/26/12
to
Le 25/04/12 07:12, jacob navia a écrit :
NOT Mr Buchert. I was MISLED by those dammed google ads where I clicked
thinking that were the books of Mr Buchardt.
I apologize for this confusion, but I wanted to set the record straight
since that book appears a bit too "creationist" to my taste, reading
some info about it.
jacob
>
> A Google search led me to the page of Thomas Buchert, that is an
> astronomer at Lyon's University that has written many papers in
> cosmology, and a very interesting book about "alternatives to the Big
> Bang theories" that I will buy tomorrow.
The authors of that book are Thomas Lepetier and J.M. Bonnet-Rideau ,
> A Google search led me to the page of Thomas Buchert, that is an
> astronomer at Lyon's University that has written many papers in
> cosmology, and a very interesting book about "alternatives to the Big
> Bang theories" that I will buy tomorrow.
NOT Mr Buchert. I was MISLED by those dammed google ads where I clicked
thinking that were the books of Mr Buchardt.
I apologize for this confusion, but I wanted to set the record straight
since that book appears a bit too "creationist" to my taste, reading
some info about it.
jacob
Phillip Helbig---undress to reply
Apr 27, 2012, 3:03:18 AM4/27/12
to
In article <mt2.0-15305...@hydra.herts.ac.uk>, Eric Flesch
Not really. There are two effects: the geometric one you describe, and
the kinematic one. They are not degenerate. In a non-empty big-bang
universe, there is first deceleration then acceleration. Compared to
the static Euclidean case, negative spatial curvature will make things
dimmer than expected. So will accelerated expansion---up to a certain
redshift. After that, things get (relatively) brighter again. This can
also distinguish cosmological effects from extinction.
the kinematic one. They are not degenerate. In a non-empty big-bang
universe, there is first deceleration then acceleration. Compared to
the static Euclidean case, negative spatial curvature will make things
dimmer than expected. So will accelerated expansion---up to a certain
redshift. After that, things get (relatively) brighter again. This can
also distinguish cosmological effects from extinction.
Eric Flesch
Apr 27, 2012, 8:21:32 AM4/27/12
to
On Fri, 27 Apr 12, Phillip Helbig wrote:
><er...@flesch.org> writes:
>> Hyperbolic space ... the shells of space are larger than 4piR <sq>,
>... So will accelerated expansion---up to a certain
positively-curved space. So 2 extra large dimensions. But I confess
to hand-waving, as I haven't got the rigorous math.
Yes, I know the static model has real problems with time dilation as a
function of redshift. I'm being agnostic about that, perhaps
unreasonably -- depends on the raw observational data, about which I'm
a bit behind the curve.
Eric
><er...@flesch.org> writes:
>> Hyperbolic space ... the shells of space are larger than 4piR <sq>,
>> so everything at R looks smaller and farther away compared with
>>flat space -- looking like "accelerating expansion".
>
>Not really. There are two effects: the geometric one you describe, and
>the kinematic one. They are not degenerate. In a non-empty big-bang
I meant static negatively-curved space.
>>flat space -- looking like "accelerating expansion".
>
>Not really. There are two effects: the geometric one you describe, and
>the kinematic one. They are not degenerate. In a non-empty big-bang
>... So will accelerated expansion---up to a certain
>redshift. After that, things get (relatively) brighter again.
So can static negative-curved space embedded in a static
positively-curved space. So 2 extra large dimensions. But I confess
to hand-waving, as I haven't got the rigorous math.
Yes, I know the static model has real problems with time dilation as a
function of redshift. I'm being agnostic about that, perhaps
unreasonably -- depends on the raw observational data, about which I'm
a bit behind the curve.
Eric
Phillip Helbig---undress to reply
Apr 28, 2012, 2:04:04 AM4/28/12
to
In article <mt2.0-10395...@hydra.herts.ac.uk>, Eric Flesch
<er...@flesch.org> writes:
> Yes, I know the static model has real problems with time dilation as a
> function of redshift.
Not just that, but there is also a stability problem.
> Yes, I know the static model has real problems with time dilation as a
> function of redshift.
Eric Flesch
Apr 29, 2012, 12:24:18 PM4/29/12
to
On Sat, 28 Apr 12, Phillip Helbig wrote:
><er...@flesch.org> writes:
>> Yes, I know the static model has real problems with time dilation as a
>
><er...@flesch.org> writes:
>> Yes, I know the static model has real problems with time dilation as a
>
>Not just that, but there is also a stability problem.
That's an old chestnut, Phil, now well expired in the era of "dark
energy" a.k.a. the cormological constant which keeps things apart,
a.k.a. "accelerating expansion" in the FRW model, a.k.a.
"gravitational scalar" in the static model. The gravitational scalar
means there is an edge, or "lip", to gravitationally bound systems,
beyond which the ambient scalar rules. So no stability problem.
And no magic involved, the scalar is gravitational action of matter
residing in the extra-dimensional bulk, a.k.a. the unseen prime mover
of the streams of galaxies.
Eric
Phillip Helbig---undress to reply
Apr 29, 2012, 3:36:14 PM4/29/12
to
In article <mt2.0-32611...@hydra.herts.ac.uk>, Eric Flesch
based on GR, Einstein's static model. It is STATIC in that it neither
expands nor contracts but it is not STABLE since it is mathematically
what is called an unstable fixed point, like a pencil balanced on its
tip. It has to be PERFECTLY balanced. Since our universe is not
EXACTLY homogeneous and isotropic, we know that it cannot be PERFECTLY
balanced.
Note also that Einstein's static model has POSITIVE spatial curvature.
Of course, there is no cosmological redshift in this model, so that
rules it out as well.
<er...@flesch.org> writes:
> On Sat, 28 Apr 12, Phillip Helbig wrote:
> ><er...@flesch.org> writes:
> >> Yes, I know the static model has real problems with time dilation as a
> >
> >Not just that, but there is also a stability problem.
>
> That's an old chestnut, Phil, now well expired in the era of "dark
> energy" a.k.a. the cormological constant which keeps things apart,
> a.k.a. "accelerating expansion" in the FRW model, a.k.a.
> "gravitational scalar" in the static model. The gravitational scalar
> means there is an edge, or "lip", to gravitationally bound systems,
> beyond which the ambient scalar rules. So no stability problem.
What you seem to be describing is the very first cosmological model
> On Sat, 28 Apr 12, Phillip Helbig wrote:
> ><er...@flesch.org> writes:
> >> Yes, I know the static model has real problems with time dilation as a
> >
> >Not just that, but there is also a stability problem.
>
> That's an old chestnut, Phil, now well expired in the era of "dark
> energy" a.k.a. the cormological constant which keeps things apart,
> a.k.a. "accelerating expansion" in the FRW model, a.k.a.
> "gravitational scalar" in the static model. The gravitational scalar
> means there is an edge, or "lip", to gravitationally bound systems,
> beyond which the ambient scalar rules. So no stability problem.
based on GR, Einstein's static model. It is STATIC in that it neither
expands nor contracts but it is not STABLE since it is mathematically
what is called an unstable fixed point, like a pencil balanced on its
tip. It has to be PERFECTLY balanced. Since our universe is not
EXACTLY homogeneous and isotropic, we know that it cannot be PERFECTLY
balanced.
Note also that Einstein's static model has POSITIVE spatial curvature.
Of course, there is no cosmological redshift in this model, so that
rules it out as well.
Eric Flesch
Apr 30, 2012, 5:13:11 AM4/30/12
to
On Sun, 29 Apr 12, Phillip Helbig wrote:
>What you seem to be describing is the very first cosmological model
>based on GR, Einstein's static model. ...
>What you seem to be describing is the very first cosmological model
No, Einstein's model had no extra-dimensional bulk. However, I wasn't
trying to present a model here. Whatever the merits, Haldane's view
that the universe is "queerer than we can suppose" is best, I think.
(But as an aside, there are papers from gr-qc on the bulk, but they
always treat the bulk as empty -- ludicrously.)
Science is in a funk these days, where each discipline is too keen to
enforce the "right" thinking, by awarding funding and tenure to the
"right" thinkers only. Who can get a astronomy degree or tenure. or
funding nowadays, advocating a static model? This isn't because it
can't be made to work -- it can. But it's starved of funding. The
only such funded theoreticians are in associated disciplines like
General Relativity & Quantum Cosmology or HEP, and even they are
careful to put an FRW context on their efforts, even though the static
alternatives are viable. In this way, however, cosmological progress
will come only from these outside disciplines. I hope I am wrong in
my pessimism, although happy to have progress from any quarter.
So currently the FRW parameters are being set by our SNIa
observations. These are the standard candles du jour, and we all love
standard candles. But that doesn't justify our use of them. Remember
how Cepheids turned out to have two separate populations. Now SN
observations show that there are two phases, first there is a
flare-dominated explosion, then a dust-and-debris dominated expansion.
The first part (given the SNIa model) should be quite standard but is
very brief and usually passes before we capture it, then the second
part has chaotic shrouding of the bright core by the expanding debris
-- so the SNIa is brighter or not depending on how shrouded it is in
our line of sight. So, not so "standard" a candle. But currently
nobody is worried about that, the paradigm is set, and everybody can
publish the latest observations using the SNIa standard candle. Maybe
in a few years the foundations will be thrown open to question -- I
actually saw an ArXiv paper about this a week or two ago, but
frustratingly can't find it now.
So my point, Phil, is that you speak with great certainty, and you
shouldn't. Cheers.
Eric
Phillip Helbig---undress to reply
May 1, 2012, 1:25:39 AM5/1/12
to
In article <mt2.0-3995...@hydra.herts.ac.uk>, Eric Flesch
the "right thinking" of the 1990s. I don't see the situation as
desperate as you paint it.
> Who can get a astronomy degree or tenure. or
> funding nowadays, advocating a static model? This isn't because it
> can't be made to work -- it can.
If you know that, then why do you need funding? You can publish a paper
without funding.
> So currently the FRW parameters are being set by our SNIa
> observations.
Not only. The interesting thing is that one gets consistent results
from th SNIa on one hand and from other tests WITHOUT the SNIa on the
other.
> Now SN
> observations show that there are two phases, first there is a
> flare-dominated explosion, then a dust-and-debris dominated expansion.
> The first part (given the SNIa model) should be quite standard but is
> very brief and usually passes before we capture it, then the second
> part has chaotic shrouding of the bright core by the expanding debris
> -- so the SNIa is brighter or not depending on how shrouded it is in
> our line of sight. So, not so "standard" a candle. But currently
> nobody is worried about that, the paradigm is set, and everybody can
> publish the latest observations using the SNIa standard candle.
If this were a serious problem, then why does one get a good fit (in a
chi-square sense) for the m-z diagram for SNIa? If this were a serious
problem, one wouldn't expect to get ANY FLRW cosmological model, much
less one which agrees with other tests.
<er...@flesch.org> writes:
> Science is in a funk these days, where each discipline is too keen to
> enforce the "right" thinking, by awarding funding and tenure to the
> "right" thinkers only.
The 2011 Nobel Prize was awarded for something which went very much
> Science is in a funk these days, where each discipline is too keen to
> enforce the "right" thinking, by awarding funding and tenure to the
> "right" thinkers only.
the "right thinking" of the 1990s. I don't see the situation as
desperate as you paint it.
> Who can get a astronomy degree or tenure. or
> funding nowadays, advocating a static model? This isn't because it
> can't be made to work -- it can.
without funding.
> So currently the FRW parameters are being set by our SNIa
> observations.
from th SNIa on one hand and from other tests WITHOUT the SNIa on the
other.
> Now SN
> observations show that there are two phases, first there is a
> flare-dominated explosion, then a dust-and-debris dominated expansion.
> The first part (given the SNIa model) should be quite standard but is
> very brief and usually passes before we capture it, then the second
> part has chaotic shrouding of the bright core by the expanding debris
> -- so the SNIa is brighter or not depending on how shrouded it is in
> our line of sight. So, not so "standard" a candle. But currently
> nobody is worried about that, the paradigm is set, and everybody can
> publish the latest observations using the SNIa standard candle.
chi-square sense) for the m-z diagram for SNIa? If this were a serious
problem, one wouldn't expect to get ANY FLRW cosmological model, much
less one which agrees with other tests.
Phillip Helbig---undress to reply
May 1, 2012, 2:59:23 PM5/1/12
to
In article <mt2.0-2276...@hydra.herts.ac.uk>, Phillip
Helbig---undress to reply <hel...@astro.multiCLOTHESvax.de> writes:
> In article <mt2.0-3995...@hydra.herts.ac.uk>, Eric Flesch
Helbig---undress to reply <hel...@astro.multiCLOTHESvax.de> writes:
> In article <mt2.0-3995...@hydra.herts.ac.uk>, Eric Flesch
> <er...@flesch.org> writes:
>
> > Science is in a funk these days, where each discipline is too keen to
> > enforce the "right" thinking, by awarding funding and tenure to the
> > "right" thinkers only.
>
> The 2011 Nobel Prize was awarded for something which went very much
> the "right thinking" of the 1990s. I don't see the situation as
> desperate as you paint it.
That should read "something which went very much AGAINST the".
>
> > Science is in a funk these days, where each discipline is too keen to
> > enforce the "right" thinking, by awarding funding and tenure to the
> > "right" thinkers only.
>
> The 2011 Nobel Prize was awarded for something which went very much
> the "right thinking" of the 1990s. I don't see the situation as
> desperate as you paint it.
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