Re: CMBR and neutron stars

Dear Stever Willner:

"Steve Willner" <willner@xxxxxxxxxxxxxxx> wrote in message
news:430f95ff$1@xxxxxxxxxxxxxxxxxxxxxxxxxx
>> > No, the numbers in my previous post for
>> > "extragalactic background light" were for
>> > a position far from any local light source.
>> > From Earth, looking towards the Galactic
>> > pole, the brightness of stars fainter than
>> > mag 6 corresponds to about
>> > 110 nW m^-2 sr^-1 in visible light alone.
>> > You would have to add to that a
>> > considerable infrared contribution, and of
>> > course the brightness is much greater at
>> > lower Galactic latitudes.
>
> In article <Op9Pe.124887$E95.68584@fed1read01>,
> "N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net@xxxxxxxxxx>
> writes:

>> Do you see the m^-2 in the number you cited?
>
> Yes. I also know what it means. So does George.

I'm sure you do. However this brings up the distance to the
source(s), which you start on below.

>> *IF* the number of
>> stars is approximately constant, but the area is
>> expanding, the stellar background will decrease
>> also.
>
> Area? The energy density of the microwave background
> and of stellar light _created up to now_ both decrease as
> the fourth power of the scale factor. Do you understand why?

Yes. And the stars_future are further away, due to expansion.

>> Note how the "stellar
>> background" was sufficient to maintain the CMBRM plasma... and
>> then it wasn't.
>
> You don't think the CMB plasma was ionized by stars, do you?

No, it was sustained as being ionized by itself, most likely.
And at some point, the feedback was insufficient to maintain the
plasma, and it quenched.

> That
> would be, ummm, a non-standard view. In the standard picture,
> stars don't form until z=20 or later (age about 180 Myr, about
> 500 times older than the epoch of recombination).
>
> And yes, the 're' in recombination can be considered a
> misnomer, but the word is used as a general term for the
> physical process of an electron entering an orbit with a
> positive ion. I've even seen 'recombination' used for the
> formation of positronium.

OK.

>> >> Stellar light would likely be lower for a lone BH in deep
>> >> space,
>> >
>> > See above. The EBL is the minimum.
>>
>> So you don't feel that "local to the galactic disk" dust would
>> contribute anything worth handling on a first pass?
>
> I have no idea what you are talking about. You asked at
> some stage about the relative contributions to the energy
> density of the Universe from stars and the CMBR, and I
> gave you the answer. Were you confused because I put
> it in units of the actual measurements instead of energy
> density?

No. You stated that our observations of the CMBR, from our
position in the Milky Way, were sufficient to also describe the
background for a "free roaming" BH. I was asking if you felt the
other constituents "in-plane" with us contributed enough
additonal energy to skew the results. I'll assume not, unless
you indicate otherwise.

> If you were to go outside and measure the brightness of
> the sky, you would get a much larger number than I quoted
> for the EBL. You will, for example, get a very large number
> if you measure in the daytime.

I hope to shout!

> Even at night, you will find contributions from local sources
> including the Earth's atmosphere, the Milky Way, and
> Zodiacal light. The trick is to subtract them off to find the
> EBL, which is related to the energy density produced by
> stars (and all other sources) through the entire history of
> the Universe.
>
> The bottom line is what I wrote: the _value_ of CMBR
> energy density decreases with time. The _ratio_ of stellar
> to CMBR energy densities _increases_ with time. It isn't
> at all obvious to me whether the _value_ of the stellar
> energy density increases or decreases with time, but I
> suspect the paper by Wesson (1991 ApJ 367, 399) gives the
> answer. (The answer is closely related to Olbers Paradox.)

OK.

> I am not sure why any of this matters for the main
> argument you seem to be making.

I am trying to integrate the light influx to a BH's event horizon
over its lifespan. I want to do this for the three cases
outlined, free roaming, with a sacrificial companion, and at the
core of a galaxy (since I want to believe that we are at the very
least, very massive). I feel this is necessary for two reasons:
1) the metrics used to describe the inside of the BH, consume
outer-space to form inner-time; and
2) if there is a Universe formed inside a BH, it would require
three spatial dimensions, but only a single time coordinate...
namely the Big Bang. So with a 2D surface (assuming the
container is not 5D or higher), a third dimension, orthogonal to
the other two, will be required. Outer-time becomes the third
spatial dimension, allowing an infall onto/into a 2D surface, to
map (more or less) uniformly to a 3D+t_0 space.

> SW> And if you don't have an
> SW> optically thick plasma back then, I think you will have
> quite
> SW> some trouble to explain where all the baryons were.
>
>> Gelled into proto-galaxies (or some close kin to small BHs,
>> just
>> cooler than ~3000K), which would subtend very little compared
>> to
>> the CMBRM.
>
> Please remember my query was about redshift "a few thousand."
> Temperatures would have been >5400 K at z>2000, and the
> Universe would have been <133000 years old. What was the
> state of baryons in your putative "proto-galaxies?" Why wasn't
> the hydrogen ionized?

Would have been, but that doesn't mean it couldn't be
gravitationally bound, and doesn't mean it couldn't be some part
"iron".

> Never mind how such structures formed in such a short time;
> I'll let you assume magic properties in the cold dark matter.

I need assume no such thing. I can assume such structures were
ingested whole, or were coalesced from slightly smaller
structures.

> And never mind
> that WMAP sees exactly the angular power spectrum that
> the standard model predicts (with parameters that agree with
> the SN results).
> That could be a coincidence. :-)

No, but it could simply be interpretation based on an assumed
model.

> If you put the baryons into small black holes, how did they
> ever get out?

Why do black holes exist where galaxies form? Is the BH the
progenitor of the galaxy, or simply the end of it? Why is matter
the primary constituent of this Universe (rather than
anti-matter)? Lots of good questions, Steve. Hopefully
civilization lasts long enough to allow generations time to work
with them. I'm only concerned with what goes into them, for the
moment.

> And how do you account for the light element abundances,
> which require the baryon plasma to exist at early epochs?
> Or is that coincidence too?

The elemental abundances don't require the baryon plasma, rather
the elemental abundances *describe* the plasma. Note that (as I
have found out) iron is perfectly capable of being a black body
radiator at high temperature. As to where the light elements
came from, there is possibly a blend of two different sources:
- they infell from production in the container Universe (or its
container), or
- they were shredded down from more complex atoms in the act of
falling into the black hole before it reached a certain size.

> If you want anyone to take your "new model" seriously, you are
> going to have to address these sorts of questions. If it's too
> early for you to do that, that's fine. Just be aware that no
> one
> will take seriously any model that doesn't address them.

I have received about as much attention as I ever expected with
this one, Steve. I was pretty sure someone had enough coffin
nails to finish it before now. But it looks like it is a doable
thing, and this here mechanical engineer looks like he's the one
to do it.

>> > And certainly the event horizon is not a
>> > requirement for an accretion disk to exist. After all,
>> > neutron
>> > star accretion disks look pretty much the same as black
>> > hole accretion disks, so the disk and its radiation cannot
>> > depend on an event horizon.
>
>> Not to a "close enough is good enough" kind of guy like me!
>> ;>)
>
> I'm not sure what you are saying here. Do you think accretion
> disks
> require an event horizon? If so, why do neutron stars show
> accretion
> disks? At any rate, this is another unconventional view, one
> that
> seems to require new physics. If this is important to you, I
> suggest
> you look into the vast literature on accretion disks.

I do require an accretion disk for two of the scenarios. But
George tells me the one at the center of the Milky Way is pretty
quiescent. I suppose the one at the center of Andromeda is as
well...

>> I can never convince you or anyone else that the event
>> horizon is a physical singularity.
>
> Why do you suppose that is? :-)
>
> I think the posts so far have pretty well covered the
> standard model of the CMBR. Unless there's still
> confusion on that, I won't be responding further in this
> thread.

Thanks very much for your help. Over and out.

David A. Smith


.

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