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New Analysis of Large ARCADE-2 Radio Background Excess

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Robert L. Oldershaw

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Jul 12, 2012, 2:20:47 AM7/12/12
to
Those interested in dark matter research and radio background research
will surely want to take a close look at Condon et al, posted to
arxiv.org on 7/11. Hmmm, 7/11 :)

http://arxiv.org/abs/1207.2439

I quote from the end of section 6, which discusses the implications of
the factor of 6 radio background excess discovered in the ARCADE-2
experiment.

"If our 3.02 GHz P(D) smoothness constraint and the Fixsen et al.
(2011) 3.3 GHz excess brightness are both correct, then a very
numerous (N > 10^13 over the whole sky) and unexpected population of
radio sources not associated with galaxies has been discovered."

(1) N > 10^13 source objects

(2) Not preferentially associates with external galaxies

Could this be a vast population of previously undetected isolated
stellar-mass black holes populating the highly extended halo of the
Milky Way Galaxy?

Might Spektr-R be able to contribute important information here?

Hope springs eternal,
RLO
Discrete Scale Relativity
http://www3.amherst.edu/~rloldershaw
Fractal Cosmology

Phillip Helbig---undress to reply

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Jul 12, 2012, 3:44:05 AM7/12/12
to
In article <mt2.0-14757...@hydra.herts.ac.uk>, "Robert L.
Oldershaw" <rlold...@amherst.edu> writes:

> Could this be a vast population of previously undetected isolated
> stellar-mass black holes populating the highly extended halo of the
> Milky Way Galaxy?

If so, why are they radio sources?

> Hope springs eternal,

Die Hoffnung stirbt zuletzt. (Hope dies only after everything else
does.)

Robert L. Oldershaw

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Jul 12, 2012, 10:44:08 AM7/12/12
to
On Jul 12, 3:44 am, Phillip Helbig---undress to reply
<hel...@astro.multiCLOTHESvax.de> wrote:
> In article <mt2.0-14757-1342074...@hydra.herts.ac.uk>, "Robert L.
>
> Oldershaw" <rlolders...@amherst.edu> writes:
> > Could this be a vast population of previously undetected isolated
> > stellar-mass black holes populating the highly extended halo of the
> > Milky Way Galaxy?
>
> If so, why are they radio sources?
------------------------------------------------------------------

The leader of the research team that ran the ARCADE 2 experiment
commented that the best explanation, but certainly not the only one,
for the factor of 6 excess in the radio background was a vast
population of black holes formed in the early "universe".

My research indicates that Kerr-Newman ultracompacts can do things
that would surprise you and the physics community.

The ARCADE 2 leader told me that they were probably going to mount an
ARCADE 3 experiment, but that was at least 2 years ago. I am a bit
perplexed that the evidence for the radio background excess has not
been independently confirmed/rejected much sooner. It's a potential
game-changer and I cannot see why astrophysicists did not immediately
push forward on it.

Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity

Eric Gisse

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Jul 13, 2012, 1:54:55 AM7/13/12
to
On Thursday, July 12, 2012 9:44:08 AM UTC-5, Robert L. Oldershaw wrote:

[...]

> It&#39;s a potential
> game-changer and I cannot see why astrophysicists did not immediately
> push forward on it.
>
> Robert L. Oldershaw
> http://www3.amherst.edu/~rloldershaw
> Discrete Scale Relativity

Robert, instead of demanding that astrophysicists do specific work for you, why don't you do it yourself?

For example, the Kepler data is right there for you to analyze and show how planetary masses are quantized. Or how the stellar masses are quantized.

Why haven't you done that? I've even DONE the analysis for you, but you had no technical response to it.

Your behavior of ignoring contradictory evidence, by the way, is why you are not taken seriously.

Eric Gisse

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Jul 13, 2012, 4:48:27 AM7/13/12
to
On Thursday, July 12, 2012 1:20:47 AM UTC-5, Robert L. Oldershaw wrote:
> Could this be a vast population of previously undetected isolated
> stellar-mass black holes populating the highly extended halo of the
> Milky Way Galaxy?

Only if the following two problems can be solved:

1) You show how your numerology predicts the excess at 1.3
2) You explain how a very large body of microlensing surveys do not show your stellar mass sources.
3) How the compact objects could have significant radio luminosity but be completely quiet in the rest of the spectrum.

>
> Might Spektr-R be able to contribute important information here?

Only if one can be resolved.

>
> Hope springs eternal,
> RLO
> Discrete Scale Relativity
> http://www3.amherst.edu/~rloldershaw
> Fractal Cosmology

[Mod. note: quoted text trimmed -- mjh]

Phillip Helbig---undress to reply

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Jul 14, 2012, 3:04:31 AM7/14/12
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In article <mt2.0-11671...@hydra.herts.ac.uk>, "Robert L.
Oldershaw" <rlold...@amherst.edu> writes:

> > > Could this be a vast population of previously undetected isolated
> > > stellar-mass black holes populating the highly extended halo of the
> > > Milky Way Galaxy?
> >
> > If so, why are they radio sources?
> ------------------------------------------------------------------
>
> The leader of the research team that ran the ARCADE 2 experiment
> commented that the best explanation, but certainly not the only one,
> for the factor of 6 excess in the radio background was a vast
> population of black holes formed in the early "universe".

Do you have a direct quote, or a link to the actual statement?

Did he say stellar-mass black holes?

Why "universe" (i.e. in quotes)?

Martin Hardcastle

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Jul 15, 2012, 5:57:25 AM7/15/12
to
In article <mt2.0-14757...@hydra.herts.ac.uk>,
Robert L. Oldershaw <rlold...@amherst.edu> wrote:
>"If our 3.02 GHz P(D) smoothness constraint and the Fixsen et al.
>(2011) 3.3 GHz excess brightness are both correct, then a very
>numerous (N > 10^13 over the whole sky) and unexpected population of
>radio sources not associated with galaxies has been discovered."
>
>(1) N > 10^13 source objects
>
>(2) Not preferentially associates with external galaxies
>
>Could this be a vast population of previously undetected isolated
>stellar-mass black holes populating the highly extended halo of the
>Milky Way Galaxy?

OK, let's look at this.

First of all, the masses would have to be at the low end of
'stellar mass' -- less than about 0.1 solar mass if they provide all
the dark matter (http://adsabs.harvard.edu/abs/2005MNRAS.364..433B);
but we know that's actually ruled out by microlensing constraints, so
more likely less than about 0.01 solar masses
(http://arxiv.org/abs/astro-ph/0001272). It's not clear that there's
any mechanism for formation of such things, but that probably bothers
me more than it bothers you.

Secondly, some mechanism is needed to make them radiate in the radio.
These must be isolated black holes, so they won't be accreting
significant amounts of matter. Their Hawking temperature is way too
low to be interesting, so accretion has to be the answer. Now there is
not a lot of stuff for them to accrete out in the halo. I think the
most generous numbers for halo matter density are likely to come from
papers involving ram pressure stripping of dwarf galaxies, like this
one (http://adsabs.harvard.edu/abs/2004ApJ...603L..77P) which gives a
density of the order 10^-4 cm^-3. That gives total baryonic masses in
the halo of the order of a few x 10^10 solar masses, so it doesn't
seem too crazy.

Now let's estimate the accretion rate. Bondi accretion should be good
enough for this, since there's no reason to expect lots of angular
momentum to be involved. From
http://adsabs.harvard.edu/abs/2007MNRAS.376.1849H I take the formula

Mdot = pi rho G^2 M_BH^2/c_s^3

In SI units,

M_BH = 0.01 * 2e30 kg
G = 6.67e-11 m^3 kg^-2 s^-1
rho = 1e-4 * 1e6 * 1.67e-27 kg m^-3 (i.e. we assume hydrogen)

The thing we don't know is the sound speed, but it might be reasonable
to assume that this is something like the velocity dispersion on these
scales, ~ 100 km/s. (Sanity check -- this gives temperatures ~ 10^6 K
which is (a) a reasonable virial temperature and (b) conveniently hard
to see gas at.)

Then Mdot works out at about 1e-3 kg/s. In other words, if we can
convert the accreted material to radiation at about 10% efficiency,
which is about the maximum possible, each of these things might be
able to radiate at about 1e-3 * 0.1 * 9e16 = 1e14 W. (Less than a
trillionth of a solar luminosity, so they're certainly 'dark'...)

Let's check the Eddington luminosity for such a BH.

L_Edd = 4*Pi*G*M_BH*m_p*c/sigma_T ~ 1e29 W.

So the accretion is certainly very sub-Eddington, which almost
certainly means that we'd have something like an ADAF and that the
radiative efficiency of 10% I've used above is a gross overestimate.
But let's push on with this for now.

Fixsen et al quote the excess radio background as a power law in
antenna temperature. We can translate this to a power law in received
power: flux density S is given by

S = 8 Pi kT_b / lambda^2

(if we assume integration over the whole sky) so, as T_b has the form

T_b = T_0 (nu/nu_0)^-2.6

we have

S = 8 Pi kT_0 nu^-0.6 / (c^2 nu_0^-2.6)

where S is measured in W Hz^-1 m^-2. We can integrate this over the
region of the observed excess to get a total flux in W m^2:

S_tot = int S dnu = (20 Pi kT_0 / c^2 nu_0^-2.6)) [nu_upper^0.4 - nu_lower^0.4]

Let's take the range to be 22 MHz to 10 GHz. Then we can put in some
numbers:

S_tot = 2.5e-11 W m^(-2)

(sanity check: from the Condon et al paper, this should be of the same
order of magnitude as 34e-9*1e-26*1e13*3e9, which it is.)

Now, can our black holes provide this power? Let's very generously
assume that *all* their radiated power comes out in the band of the
ARCADE-2 excess. Let's further assume to get a number out that we have
a uniform distribution of these things out to some cutoff radius R,
and that we are in the centre of the distribution; the latter is
almost true, the former not so true, but we should get the right order
of magnitude. Then, trivially, the total flux received from all the
BHs is

S_tot_BH = n_BH L_BH R (W m^-2 as expected)

But n_BH = N_BH/((4/3)*Pi*R^3), where N_BH is the total number of BHs, so

S_tot_BH = 3 L_BH N_BH / (4*Pi*R^2)

L_BH = 1e14 W, N_BH = 1e13, and let's say R = 100 kpc; then

S_tot_BH = 2.5e-17 W

This is a factor of a million below the ARCADE-2 power. Conclusion: it
is very difficult to get this population to do what we want.

*Very* favourable assumptions I've made include that all the accretion
power from the BH comes out in the radio and that the conversion from
accretion to radiation is 10%. Slightly less favourable ones include
the temperature of the accreted medium and the mass of the BHs (but
note that the maximum possible, 0.1 M_solar, gets you only an extra
two orders of magnitude, which is not enough). The biggest uncertainty
is in the assumptions for the accretion mechanism and the densities
available for accretion. Playing around with these numbers and
checking for any mistakes is left as an exercise for the reader!

>Might Spektr-R be able to contribute important information here?

No. Its sensitivity is way, way too low to see objects of the flux
density estimated by Condon et al, independent of your model for what
they are.

Martin
--
Martin Hardcastle
School of Physics, Astronomy and Mathematics, University of Hertfordshire, UK

Eric Gisse

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Jul 15, 2012, 2:48:05 PM7/15/12
to
On Jul 15, 4:57�am, Martin Hardcastle <m.j.hardcas...@herts.ac.uk>
wrote:

[...]

Very nice analysis. Watch Robert ignore it all, or respond exclusively
to a trivial point and deliberately not respond to the rest of it :)

Another point would be "How can the black holes radiate selectively in
the radio while not forming a noticable background in the gamma and x-
ray bands?"

> *Very* favourable assumptions I've made include that all the accretion
> power from the BH comes out in the radio and that the conversion from
> accretion to radiation is 10%.

The ~10% radiative efficiency is empirically true at the SMBH scales,
but you writing that made me wonder if the efficiency is a number that
is independant of the black hole size or if it scales along with it.

I think it scales because the efficiency comes from the accretion
disk's ability to rub matter together and make it shed angular
momentum, which is going to be far weaker with smaller black holes.

[...]

Robert L. Oldershaw

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Jul 15, 2012, 2:49:06 PM7/15/12
to
On Thursday, July 12, 2012 2:20:47 AM UTC-4, Robert L. Oldershaw wrote:
> Those interested in dark matter research and radio background research
> will surely want to take a close look at Condon et al, posted to
> arxiv.org on 7/11. Hmmm, 7/11 :)
>
> http://arxiv.org/abs/1207.2439
>
---------------------------------------------------------------

This is a response to MJH's comment. I cannot seem to get the Google
software to put my post after the relevant comment, it keeps dumping
me here. So I'll make do with that.

Firstly, thank you for the effort you put into your informed and
collegial comment.

(1) We are going to have to agree to disagree on the mass issue. I am
unwilling to concede that any evidence currently available, including
all available microlensing observations, rule out my prediction that
virtually all of the dark matter mass is in the form of ultracompacts
with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.

(2) Pulsars have no trouble at all producing copious radio emissions.
Rotating, highly charged black holes can certainly do the same. Then
there is precession phenomena. Then there is the equivalent of
synchrotron radiation.

But here is the key point I would like to make. We should wait and see
what the NuSTAR observations tell us. If we do not see the high-mass
"tail" of the population of black holes that DSR predicts, then my
prediction is in serious jeopardy. On the other hand, if NuSTAR
discovers evidence for a huge and previously unknown population of
ultracompacts, then we are going to have to radically revise the
assumptions that go into your analysis of the situation.

I am hoping that empirical evidence will clarify the matter in a
reasonable amount of time.

I am happy to discuss various aspects of this subject in an objective
scientific manner, as you have done, but I have no interest in debates
or dogmatic haranges.

RLO

Richard D. Saam

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Jul 15, 2012, 5:19:49 PM7/15/12
to
On 7/12/12 1:20 AM, Robert L. Oldershaw wrote:
> Those interested in dark matter research and radio background research
> will surely want to take a close look at Condon et al, posted to
> arxiv.org on 7/11. Hmmm, 7/11 :)
>
> http://arxiv.org/abs/1207.2439

that references a previous more comprehensive paper

http://arxiv.org/abs/1108.0569v1
In that paper,
Equation 1 represented in Figure 1,
the excess above CMB at 3.02 GHz looks to be insignificant
relative to log log linear excess above CMB at
22, 45, 408, and 1420 MHz
or
...022, .045, .408, and 1.420 GHz

How is the log log linear nature
of this isotropic diffuse excess above any known source
explained?

Richard D Saam

Phillip Helbig---undress to reply

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Jul 15, 2012, 5:20:30 PM7/15/12
to
In article <mt2.0-17179...@hydra.herts.ac.uk>, "Robert L.
Oldershaw" <rlold...@amherst.edu> writes:

> (1) We are going to have to agree to disagree on the mass issue. I am
> unwilling to concede that any evidence currently available, including
> all available microlensing observations, rule out my prediction that
> virtually all of the dark matter mass is in the form of ultracompacts
> with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.

Leaving aside the quantization for the moment, do you have any idea why
only you and Mike Hawkins believe that microlensing observations do not
rule out such objects being virtually all of the dark matter?

Can you describe an experiment which would, at least in principle, be
able to rule this out? Otherwise it's not a scientific hypothesis.

> But here is the key point I would like to make. We should wait and see
> what the NuSTAR observations tell us. If we do not see the high-mass
> "tail" of the population of black holes that DSR predicts, then my
> prediction is in serious jeopardy.

How serious is this jeopardy compared to the observed lack of
substructure in the electron? The same paper made the "definitive
prediction" of substructure in the electron at a scale which, at the
time, was not observable but now is. Normally, when a theory fails its
own definitive prediction, the theory is ruled out.

craig.m...@gmail.com

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Jul 16, 2012, 4:04:22 AM7/16/12
to
On Sunday, July 15, 2012 2:49:06 PM UTC-4, Robert L. Oldershaw wrote:
> But here is the key point I would like to make. We should wait and see
> what the NuSTAR observations tell us. If we do not see the high-mass
> &quot;tail&quot; of the population of black holes that DSR predicts, then my
> prediction is in serious jeopardy. On the other hand, if NuSTAR
> discovers evidence for a huge and previously unknown population of
> ultracompacts, then we are going to have to radically revise the
> assumptions that go into your analysis of the situation.

Is these your claimed 10^{29} erg/s sources, the ones that would be impossible for NuSTAR to detect because they are too faint?

CM

Eric Gisse

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Jul 16, 2012, 4:05:13 AM7/16/12
to
On Jul 15, 1:49�pm, "Robert L. Oldershaw" <rlolders...@amherst.edu>
wrote:
> On Thursday, July 12, 2012 2:20:47 AM UTC-4, Robert L. Oldershaw wrote:
> > Those interested in dark matter research and radio background research
> > will surely want to take a close look at Condon et al, posted to
> > arxiv.org on 7/11. Hmmm, 7/11 :)
>
> >http://arxiv.org/abs/1207.2439
>
> ---------------------------------------------------------------
>
> This is a response to MJH's comment. I cannot seem to get the Google
> software to put my post after the relevant comment, it keeps dumping
> me here. So I'll make do with that.
>
> Firstly, thank you for the effort you put into your informed and
> collegial comment.
>
> (1) We are going to have to agree to disagree on the mass issue. I am
> unwilling to concede that any evidence currently available, including
> all available microlensing observations, rule out my prediction that
> virtually all of the dark matter mass is in the form of ultracompacts
> with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.

We already know you aren't willing to concede, Robert.

What is missing is the technical argument you are basing this on. You
have had years and years to scrutinize the literature and publish a
counter argument but you have not taken that opportunity.

You've even had plenty of time here, but still no technical argument.
What do you call a person who sees all the available evidence and
disregards it?

>
> (2) Pulsars have no trouble at all producing copious radio emissions.
> Rotating, highly charged black holes can certainly do the same. Then
> there is precession phenomena. Then there is the equivalent of
> synchrotron radiation.

Buhwuh?

So much to work through here.

1) Why are you mentioning pulsars, which are completely different
objects that produce emissions in a completely different manner from
that of black holes?
2) What is your mechanism for keeping a black hole charged in a plasma
environment?
2) Why are you bringing up precession?
4) Synchrotron radiation requires a strong magnetic field. A neutron
star envrionment can have an exceedingly wide range of magnetic
fields, while the fields around a black hole are of the single tesla
order of magnitude.

>
> But here is the key point I would like to make. We should wait and see
> what the NuSTAR observations tell us. If we do not see the high-mass
> "tail" of the population of black holes that DSR predicts, then my
> prediction is in serious jeopardy.

You don't get to decide what puts your numerology in "jeopardy".

There is more than enough available evidence to disregard your
numerology. NuSTAR won't change anything.

> On the other hand, if NuSTAR
> discovers evidence for a huge and previously unknown population of
> ultracompacts, then we are going to have to radically revise the
> assumptions that go into your analysis of the situation.

Through what mechanism do you believe NuSTAR will accomplish this even
though previous x-ray telescopes have not?

>
> I am hoping that empirical evidence will clarify the matter in a
> reasonable amount of time.

Remember when you asked Martin Hardcastle to analyze the masses of the
eclipsing binary list and how you completely ignored the results of
that?

There is literally no reason to believe you will change your argument
in the face of falsifying evidence.

That reminds me, when are you going to prove my analysis was biased
against you like you claimed?

>
> I am happy to discuss various aspects of this subject in an objective
> scientific manner, as you have done, but I have no interest in debates
> or dogmatic haranges.

You don't have any interest in debates because you keep losing them.

Please remember that this newsgroup is not your personal soapbox that
exists only to give you a comfortable environment to talk about your
own personal numerology.

Now, have you made any efforts in analyzing stellar and planetary
masses yet? You've had nearly a whole calender year since I gave you
the data, and all the free time in the world. I await your publication
showing how the data supports your numerology.


>
> RLOhttp://www3.amherst.edu/~rloldershaw
> Discrete Scale Relativity

Martin Hardcastle

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Jul 17, 2012, 6:28:59 PM7/17/12
to
In article <mt2.0-17179...@hydra.herts.ac.uk>,
Robert L. Oldershaw <rlold...@amherst.edu> wrote:
>(1) We are going to have to agree to disagree on the mass issue. I am
>unwilling to concede that any evidence currently available, including
>all available microlensing observations, rule out my prediction that
>virtually all of the dark matter mass is in the form of ultracompacts
>with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.

What do you think is wrong with the MACHO collaboration's analysis?

>(2) Pulsars have no trouble at all producing copious radio emissions.
>Rotating, highly charged black holes can certainly do the same.

That's not 'certain'. Pulsars emit because the neutron star behaves
like a rapidly rotating magnetic dipole. Standard black holes cannot
do this; they don't have a magnetic field (no-hair theorem).

> Then
>there is precession phenomena.

How does that give rise to emission?

> Then there is the equivalent of
>synchrotron radiation.

Sure. But that has to be powered by accretion -- as indeed it is in
many other black hole systems. And my analysis works out the available
power for accretion, and then puts it *all* into radio emission
(modulo an efficiency factor); that is, it's the most favourable
assumption possible for your model unless you can find a way of
tapping the mass-energy of the black hole itself.

>But here is the key point I would like to make. We should wait and see
>what the NuSTAR observations tell us. If we do not see the high-mass
>"tail" of the population of black holes that DSR predicts, then my
>prediction is in serious jeopardy.

My accretion calculation, being independent of the wavelength, works
just as well for NuSTAR. So you can go off and find the sensitivity of
NuSTAR and work out how close one of these things will need to be to
be visible in finite time, assuming that all of the energy comes out
in the NuSTAR band instead of the radio band. You'll find that the
answer is 'very close indeed'. If these things existed, and behaved as
it would be reasonable to expect them to behave, they would be
incredibly hard to see.

Martin Hardcastle

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Jul 17, 2012, 6:30:12 PM7/17/12
to
In article <mt2.0-17147...@hydra.herts.ac.uk>,
Eric Gisse <jow...@gmail.com> wrote:
>Another point would be "How can the black holes radiate selectively in
>the radio while not forming a noticable background in the gamma and x-
>ray bands?"

Well, quite. But in some ADAF-type models I think the emission is
mostly at very low frequencies -- although then the efficiency would
be way lower than I have assumed.

The point is that if the hypothesis doesn't work even on the most
favourable assumptions, we can discard it without having to worry
about such things. We don't care if there's a magic process that
channels all of the radiated energy into the band of the ARCADE-2
excess if, as I argue, it still doesn't work by 6 orders of magnitude.

>The ~10% radiative efficiency is empirically true at the SMBH scales,
>but you writing that made me wonder if the efficiency is a number that
>is independant of the black hole size or if it scales along with it.
>
>I think it scales because the efficiency comes from the accretion
>disk's ability to rub matter together and make it shed angular
>momentum, which is going to be far weaker with smaller black holes.

Well, we know that stellar-mass black holes in binary systems, fed by
Roche lobe overflow, can be pretty efficient at converting mass into
energy -- certainly around the 10% level I assumed. They have 'proper'
accretion disks like those of AGN, despite being ~10^7 times less
massive. But that's when they're being fed at rates comparable to the
Eddington rate, which is basically the scaling accretion rate for
these systems. If the accretion rate is many orders of magnitude lower
than Eddington, as I'm suggesting, then *both* stellar-mass BH and
SMBH would be expected to be radiatively inefficient for exactly the
reason you state -- you can't sustain a viscously dissipative
accretion disc. (These radiatively inefficient accretion flows, where
most of the energy in the infalling material disappears across the
event horizon, are the ADAFs -- advection dominated accretion flows --
that I have been mentioning.) Thus, again, the assumption I've made is
way more favourable than is realistic for the sake of getting a
completely conservative estimate of whether the model is viable --
which it is not.

Robert L. Oldershaw

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Jul 18, 2012, 2:59:02 AM7/18/12
to
On Tuesday, July 17, 2012 6:28:59 PM UTC-4, Martin Hardcastle wrote:
> In article &lt;mt2.0-17179...@hydra.herts.ac.uk>,
> Robert L. Oldershaw &lt;rlold...@amherst.edu> wrote:
> >(1) We are going to have to agree to disagree on the mass issue. I am
> >unwilling to concede that any evidence currently available, including
> >all available microlensing observations, rule out my prediction that
> >virtually all of the dark matter mass is in the form of ultracompacts
> >with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.
>
> What do you think is wrong with the MACHO collaboration's analysis?
>
As I have mentioned here a couple of times before, there are assumptions that relate to the spatial distribution of the MACHOs and to their velocity distribution. No doubt there are other assumptions involved in their conclusion that no more than 20% of the DM could be MACHOs. Maybe they are right, and then again maybe nature does not obey their simple and reasonable assumptions.

My hope is for a fairly clean test that does not require many untested
assumptions. I am hoping that NuSTAR will offer that kind of test.

I am only willing to discuss one issue at a time because when I put a
lot of time into responses people ignore all but the one weakest
point, and then hammer away at that. By sticking to one issue at a
time, the process is more efficient.

I cannot remember anyone acknowledging any positive things about
Discrete Scale Relativity. Aside from the fact that it might be
totally wrong, if one does not appreciate the elegance and potential
for unification offered by this new paradigm, then I think one is a
member of Swift's confederacy.

Perhaps my best strategy is to present relevant empirical evidence and
let it go at that.

Sorry, but this is getting a bit depressing.

Robert L. Oldershaw
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity

Paraphrase of J. Swift: 'When a really good and completely novel idea
appears in this world, you will know it by this sign, that the dunces
are all in confederacy against it.'

[Mod. note: random HTML removed. Paraphrase of C. Sagan: The fact that
some geniuses were laughed at does not imply that all who are laughed
at are geniuses. -- mjh]

Eric Gisse

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Jul 18, 2012, 3:01:09 AM7/18/12
to
On Tuesday, July 17, 2012 5:28:59 PM UTC-5, Martin Hardcastle wrote:
> In article &lt;mt2.0-17179...@hydra.herts.ac.uk> ,
> Robert L. Oldershaw &lt;rlold...@amherst.edu> wrote:
> > (1) We are going to have to agree to disagree on the mass issue. I am
> > unwilling to concede that any evidence currently available, including
> > all available microlensing observations, rule out my prediction that
> > virtually all of the dark matter mass is in the form of ultracompacts
> > with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.
>
> What do you think is wrong with the MACHO collaboration's analysis?
>

Bonus question:

Why is the MOA group analysis acceptable while other group's results are not?

That is, of course, putting aside the fact that their work still falsifies the numerology but my point stands.

[..]

Eric Gisse

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Jul 19, 2012, 2:04:29 AM7/19/12
to
On Wednesday, July 18, 2012 1:59:02 AM UTC-5, Robert L. Oldershaw wrote:
> On Tuesday, July 17, 2012 6:28:59 PM UTC-4, Martin Hardcastle wrote:
> > In article <mt2.0-17179...@hydra.herts.ac.uk> ,
> > Robert L. Oldershaw <rlold...@amherst.edu> wrote:
> > > (1) We are going to have to agree to disagree on the mass issue. I am
> > > unwilling to concede that any evidence currently available, including
> > > all available microlensing observations, rule out my prediction that
> > > virtually all of the dark matter mass is in the form of ultracompacts
> > > with masses of 8 x 10^-5, 0.145 and 0.580 solar masses.
> >
> > What do you think is wrong with the MACHO collaboration's analysis?
> >

> As I have mentioned here a couple of times before, there are
assumptions that relate to the spatial distribution of the MACHOs
and to their velocity distribution.

You do know how the analysis works, right? Telescopes observe the LMC
and look for lensing events characteristic of objects. The lensing
events are analyzed and based on the transit time and frequency of the
transits a density of compact objects can be determined.

It is somewhat concerning that you still don't seem to have a firm
grasp of the methodology.

If you think the analysis is unfair, take the raw data and analyze it
yourself. You have had this opportunity and have been told to take
advantage of it but haven't thus far. Why?

> No doubt there are other assumptions involved in their conclusion
that no more than 20% of the DM could be MACHOs. Maybe they are
right, and then again maybe nature does not obey their simple and
reasonable assumptions.

What do you mean by "no doubt" ? The publications are very clear on
the assumptions and methodology. In fact, you've cited the primary
reference on the subject in your own paper so I'm unclear as to how
you can make this argument.

If you don't know what's being assumed you probably should not be
complaining that the answer isn't what you want it to be.

Besides, the 20% figure is a bit high. It's more like 5% if you look
at the OGLE III analysis depending what kind of objects you assume.
I've given you this data before so it is a little surprising to see
you are not representing it correctly.

>
> My hope is for a fairly clean test that does not require many untested
> assumptions. I am hoping that NuSTAR will offer that kind of test.

Even though it has been shown that NuSTAR doesn't have the sensitivity
to get what you want?

What exactly is your expectation here, other than a miracle? Why not
stick with the resources that can actually do what you want? Is it
because they don't give you the answer you want?

What happens when NuSTAR doesn't give you the answer you want?

>
> I am only willing to discuss one issue at a time because when I put a
> lot of time into responses people ignore all but the one weakest
> point, and then hammer away at that.

I'm sorry Robert, at what point did it become the case that you are
the one who controls the argument?

I think its' about time you had a serious think about what you are
expecting to happen here.

First off, you already know this is an inappropriate medium for new
ideas. You had already gotten your material published in ApJ at one
point so you should probably try publishing in actual journals.

If your material is being rejected by the journals, you should
probably think about what that means before seeking a new forum for
your thoughts.

Next, are you even trying? This is a serious question.

I personally have given you one data resource after another, even
doing the analysis for you in one instance, that would be what you
would need to do to get evidence for your numerology. You haven't
lifted a finger.

So if you aren't willing to do the work, what exactly is your goal here?

This is a research newsgroup. This isn't your personal homepage in
which you control, please don't treat it as such.

>By sticking to one issue at a
> time, the process is more efficient.

No, what would be more efficient is you writing up your findings and
publishing them in a journal rather than spamming various blogs and
comment sections that I frequent?

>
> I cannot remember anyone acknowledging any positive things about
> Discrete Scale Relativity.

Probably because there aren't any. Its' failings have been discussed
repeatedly by myself and others and ignored by you.

Perhaps you should not have your ego so invested in this.

> Aside from the fact that it might be
> totally wrong,

s/might/is/

> if one does not appreciate the elegance and potential
> for unification offered by this new paradigm, then I think one is a
> member of Swift's confederacy.

40 points for claiming that the "scientific establishment"
is engaged in a "conspiracy" to prevent your work from gaining its
well-deserved fame, or suchlike."

>
> Perhaps my best strategy is to present relevant empirical evidence and
> let it go at that.

Like every other scientist?

See my previous comment about this being the inappropriate forum for
this kind of thing.

>
> Sorry, but this is getting a bit depressing.

Maybe you should take your ego out of this?

Your ego is making it hard for you to discuss this objectively.

[Mod. note: random html removed again, and lines reformatted; please
fix your interface, Google! -- mjh]
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