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Quasar found 13 billion years away



 
 
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  #1  
Old June 20th 07, 05:10 PM posted to sci.astro.research
jacob navia
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Posts: 341
Default Quasar found 13 billion years away

[[Mod. note -- I apologise to the author and the s.a.r readership
for the week-long delay in posting this article, which arrived at my
institution's mail system on
Thu, 14 Jun 2007 13:59:45 +0200
but was mistakenly categorized as spam by an over-eager (and *not*
user-configurable) spam filter. I just now discovered it when cleaning
out the spam folder. I will try to do this more frequently in the future.
If it's any consolation, computer support just sent around a message
today that they're preparing to switch to a new spam filter... -- jt]]

Kent Paul Dolan wrote:
I don't see anything useful to be accomplished
by trying to twist every new find at the limits
of our current vision into some "counter-argument"
to the Big Bang, though, as the OP persists in
doing, despite the twisting given to each piece of
evidence being promptly debunked.


"Debunked" is an emotionally laden word. It is not
unreasonable to point to a quasar in just 500
million years being too fast to believe. I quoted the
original researcher saying the same.

This is the obsessive behavior typical of those
trying to square the circle or trisect the angle
for lifetimes after it is proved impossible with
standard tools of Euclidean geometry constructions.


This is just polemic. Trying to obsessively establish
what I consider the truth is a behavior I consider
correct. I could argue that you compulsively try
to establish the BB as the truth, but that would
not lead the discussion anywhere. I think that a
calm discussion without any emotional undertones is
the best for exchanging points of view.

So long as the cosmic microwave background
radiation continues to shine, and it shows no sign
of going away, the universe keeps testifying for
all to understand: "I had a beginning, and in
that beginning, things were different from today".


Taking out that "beginning" words (In the beginning
was the bang, and the bang cooled and created light...
That sounds familiar and it is maybe the deep reason
for my distaste of the BB theory)

I asked a question concerning this, but apparently it got
lost. It was basically this:

What physical evidence we have that the CMB is not just
radiation coming from a diluted hydrogen cloud whose mean
temperature is 2.7K and whose radius is (say) 20 billion
years?

And if we were in the middle of such a HUGE cloud?

And that would be just *one* of the explanations for the
CMB that doesn't require a big bang or a "beginning".

Why is this so hard for some people to accept?

xanthian.


Yes, why would that be so difficult to accept?

jacob
  #2  
Old June 23rd 07, 09:17 AM posted to sci.astro.research
George Dishman[_1_]
external usenet poster
 
Posts: 2,509
Default Quasar found 13 billion years away

"jacob navia" wrote in message
...
.....
Taking out that "beginning" words (In the beginning
was the bang, and the bang cooled and created light...
That sounds familiar and it is maybe the deep reason
for my distaste of the BB theory)

I asked a question concerning this, but apparently it got
lost. It was basically this:

What physical evidence we have that the CMB is not just
radiation coming from a diluted hydrogen cloud whose mean
temperature is 2.7K and whose radius is (say) 20 billion
years?


The evidence is the observed Hubble red shift. Take
the cloud and divide it into thin spherical shells.
We see some light from each shell but more distant
shells are red shifted to a greater degree. If the
cloud is at a uniform temperature, we should see
the integral of the redshifted curves. Ned Wright
produced a similar curve based on the CMBR being
red shifted starlight to illustrate the problem:

http://www.astro.ucla.edu/~wright/Stolmar_Errors.html

And if we were in the middle of such a HUGE cloud?


Yes, we would have to be at the centre, but the
model only works if the temperature is proportional
to the radius from us so that the redshifted
temperature is 2.7K for all shells. The cloud has
to have a spherically symmetric temperature profile
with the lowest temperature of 0K at the centre,
exactly where our galaxy is situated, but the
temperature 13.7 billion light years away is 3000K.

And that would be just *one* of the explanations for the
CMB that doesn't require a big bang or a "beginning".

Why is this so hard for some people to accept?

xanthian.


Yes, why would that be so difficult to accept?


It is difficult to accept because there is no good
explanation for how a cloud could maintain such a
strange temperature profile without the gas at the
centre being warmed to equilibrium, and personally
I find the idea that the universe is centred on the
Earth even more distasteful than a beginning with a
homogenous and isotropic universe.

On the other hand, the cooling of a dense cloud to the
point where it becomes transparent at around 3000K is
not unlike looking at the surface of the Sun where we
see the outer surface of the opaque layers.

That, the evolution of galaxy structures, the ages of
stars, elemental abundances and the red shift itself
all point to the same conclusion, the matter in the
universe was denser and hotter in the past. Whether
that implies a "beginning" in the classical sense is
another matter until we can reconcile GR and QM but
whether you find the idea distasteful or not will not
change the nature of the universe, either it did or it
didn't regardless of our opinions.

George
  #3  
Old June 25th 07, 02:05 PM posted to sci.astro.research
Chalky
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Posts: 219
Default Quasar found 13 billion years away

On Jun 23, 9:17 am, George Dishman wrote:
"jacob navia" wrote in message

...


What physical evidence we have that the CMB is not just
radiation coming from a diluted hydrogen cloud whose mean
temperature is 2.7K


I assume here the implied qualification: "post redshift"

and whose radius is (say) 20 billion
years?


The evidence is the observed Hubble red shift. Take
the cloud and divide it into thin spherical shells.
We see some light from each shell but more distant
shells are red shifted to a greater degree. If the
cloud is at a uniform temperature, we should see
the integral of the redshifted curves. Ned Wright
produced a similar curve based on the CMBR being
red shifted starlight to illustrate the problem:

http://www.astro.ucla.edu/~wright/Stolmar_Errors.html

And if we were in the middle of such a HUGE cloud?


Yes, we would have to be at the centre, but the
model only works if the temperature is proportional
to the radius from us so that the redshifted
temperature is 2.7K for all shells.


Absolutely. This is the crux of the matter.

The cloud has
to have a spherically symmetric temperature profile


And what is wrong with that? The same is true, in essence, within
classical BB theory, for increasing z, no matter what cosmological
parameters you choose.

with the lowest temperature of 0K at the centre,


Why?

exactly where our galaxy is situated, but the
temperature 13.7 billion light years away is 3000K.

And that would be just *one* of the explanations for the
CMB that doesn't require a big bang or a "beginning".


Why is this so hard for some people to accept?


xanthian.


Yes, why would that be so difficult to accept?


It is difficult to accept because there is no good
explanation for how a cloud could maintain such a
strange temperature profile without the gas at the
centre being warmed to equilibrium,


Expansion and accelerating expansion potentially account for that.
Otherwise you are essentially re-introducing Olber's paradox at a
lower EM frequency range.

Incidentally, what, precisely, is the z/T relationship predicted by
EFE? (I honestly don't remember)

and personally
I find the idea that the universe is centred on the
Earth even more distasteful than a beginning with a
homogenous and isotropic universe.


AHA! Back to the foundations of natural philosophy, I am pleased to
see! It has been pointed out (by prior authors) that Einstein's
general principle (also attributed {by some} to Galileo), puts the cat
amongst the pigeons in this respect. Stated pregeometrically, all
bodies of ref. are equiv. for formulating general laws of nature.
Hence coordinates centred around the observer are as good as any
other. Thus, the pre-Copernican and Copernican approaches are
equivalently valid in this relativistic respect. This is the "sting in
the tail" of GR theory, and greater authors than me have made this
point before.

On the other hand, the cooling of a dense cloud to the
point where it becomes transparent at around 3000K is
not unlike looking at the surface of the Sun where we
see the outer surface of the opaque layers.


Agreed

[snip]

George


Touchee, Chalky.
  #4  
Old June 26th 07, 09:06 AM posted to sci.astro.research
Kent Paul Dolan
external usenet poster
 
Posts: 225
Default Quasar found 13 billion years away

Chalky wrote:
George Dishman wrote:


The cloud has to have a spherically symmetric
temperature profile


And what is wrong with that? The same is true, in
essence, within classical BB theory, for
increasing z, no matter what cosmological
parameters you choose.


Because the diameter of the observable universe is
larger than the radius of the observable universe,
so unless they were once nearby one another [and
inflation makes the math work that puts them "nearby
enough"], the part in front of us hasn't yet had
enough time (by half) to communicate to the part in
back of us, "hey, let's all be _this_ temperature".

That leaves sheer coincidence as the remaining
mechanism for the observed smoothness of the CMBR,
if past propinquity is denied, and scientists
pretty much universally distrust coincidences of
that ubiquity.

xanthian.
  #5  
Old June 26th 07, 09:13 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jun 25, 2:05 pm, Chalky wrote:
On Jun 23, 9:17 am, George Dishman wrote:

"jacob navia" wrote in message


...
What physical evidence we have that the CMB is not just
radiation coming from a diluted hydrogen cloud whose mean
temperature is 2.7K


I assume here the implied qualification: "post redshift"





and whose radius is (say) 20 billion
years?


The evidence is the observed Hubble red shift. Take
the cloud and divide it into thin spherical shells.
We see some light from each shell but more distant
shells are red shifted to a greater degree. If the
cloud is at a uniform temperature, we should see
the integral of the redshifted curves. Ned Wright
produced a similar curve based on the CMBR being
red shifted starlight to illustrate the problem:


http://www.astro.ucla.edu/~wright/Stolmar_Errors.html


And if we were in the middle of such a HUGE cloud?


Yes, we would have to be at the centre, but the
model only works if the temperature is proportional
to the radius from us so that the redshifted
temperature is 2.7K for all shells.


Absolutely. This is the crux of the matter.

The cloud has
to have a spherically symmetric temperature profile


And what is wrong with that? The same is true, in essence, within
classical BB theory, for increasing z, no matter what cosmological
parameters you choose.


Hmmm....

Looked at simply,

F is proportional to 1/r*r
P=F/A (definition of pressure)
hence P is proportional to 1/r*r*r*r
but V is proportional to r*r*r,
and PV=nRT (ideal gas law).
Thus 1/r is proportional to T
so, if r is proportional 1/(1+z),
T is proportional to redshift.

When 1+z~1000, T~3000
When 1+z~1, T~3

So, why wouldn't the thermal radiation from this known expanding cloud
of hot transparent gas, after the surface of last scattering, produce,
or, at least, contribute to, the observed CMB spectrum?

If something re-absorbs that thermal radiation, why does it not
simultaneously re-absorb the classically predicted CMBR, which we are
taught was only released at this surface of last scattering?
  #6  
Old June 26th 07, 10:11 AM posted to sci.astro.research
Oh No
external usenet poster
 
Posts: 433
Default Quasar found 13 billion years away

Thus spake Kent Paul Dolan
Chalky wrote:
George Dishman wrote:


The cloud has to have a spherically symmetric
temperature profile


And what is wrong with that? The same is true, in
essence, within classical BB theory, for
increasing z, no matter what cosmological
parameters you choose.


Because the diameter of the observable universe is
larger than the radius of the observable universe,
so unless they were once nearby one another [and
inflation makes the math work that puts them "nearby
enough"], the part in front of us hasn't yet had
enough time (by half) to communicate to the part in
back of us, "hey, let's all be _this_ temperature".

That leaves sheer coincidence as the remaining
mechanism for the observed smoothness of the CMBR,
if past propinquity is denied, and scientists
pretty much universally distrust coincidences of
that ubiquity.

One cannot draw definite conclusions about the predictions of a model of
quantum gravity which we do not yet have.

Regards

--
Charles Francis
moderator sci.physics.foundations.
substitute charles for NotI to email
  #7  
Old June 26th 07, 10:35 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jun 26, 9:06 am, Kent Paul Dolan wrote:
Chalky wrote:
George Dishman wrote:
The cloud has to have a spherically symmetric
temperature profile

And what is wrong with that? The same is true, in
essence, within classical BB theory, for
increasing z, no matter what cosmological
parameters you choose.


Because the diameter of the observable universe is
larger than the radius of the observable universe,


This is a semantic argument not a physical one. It is true that the
distance to the big bang is ~13.7 billion lyr in all directions, but
this does not mean that the bb had a diameter of ~37.4 billion lyr,
13.7 billion yr ago.

You have thus missed my real point, which is as follows:

Closer to us than the surface of last scattering, we should 'see'
successively closer shells of successively cooler gas, which should
emit thermal radiation, according to temperature. However, if the
temperature increases with redshift, and that radiation is, by
definition, redshifted by that redshift, all successive shells should
reinforce a black body 2.7K spectrum, when measured in the here and
now. If we don't see that spectrum, why, not? And, since we do see
that spectrum, why do we assume that it all came from z=1069

Chalky
  #8  
Old June 27th 07, 10:25 AM posted to sci.astro.research
Kent Paul Dolan
external usenet poster
 
Posts: 225
Default Smoothing the Universe (was: Quasar found 13 billion years away)

Chalky wrote:

This is a semantic argument not a physical one.


No, it's not. The argument is entirely a physical
one. You don't see it because you are using a
failing intuition for the problem.

It is true that the distance to the big bang is
~13.7 billion lyr in all directions, but this does
not mean that the bb had a diameter of ~37.4
billion lyr, 13.7 billion yr ago.


That's not a useful argument, nor is it required.

Try to be a bit more alert to the sheer simplicity
of the situation.

The light (and _any other_ form of signal) from the
farthest observable universe, _by definition_, just
reached _us_.

The problem is spherically symmetrical.

Thus, regardless of _anything_ happening in between,
by sheer symmetry, the light from the farthest
observable universe "in front of us" has _not_ yet
had time to reach the farthest observable universe
"in back of us".

Elsewhere, you make arguments in terms of the ideal
gas law, but those arguments fail for exactly the
same reason: no mechanism exists, absent initial
propinquity, for communicating to the farthest
observable universe along one radius of the diameter
"from here" the _gas pressure_ of the farthest
observable universe along the opposite radius, so
there is no reason for the two pressures to resemble
one another _at all_, so any argument based on them
being spherically symmetrical fails from the outset.

The problem is perfectly general, for _any_ physical
constant: you can't get the information that makes
things smooth from one end of that diameter to the
other end of that diameter in the existing lifetime
of the observable (and thus from our point of view
"communicating with us") universe, absent arguments
that said diameter was at one time small enough that
considerations of propinquity allowed that
communication to occur and the observed smoothness
of the resulting CMBR (or of anything _else_ you
claim to be spherically symmetrical like the CMBR
is) to be other than coincidental.

Occam's razor then dismisses such claims of the CMBR
being spherically symmetrical and smooth "by
coincidence".

Quantum valeat.

xanthian.
  #9  
Old June 27th 07, 01:19 PM posted to sci.astro.research
[email protected]
external usenet poster
 
Posts: 96
Default Quasar found 13 billion years away

On 25 Jun, 14:05, Chalky wrote:
On Jun 23, 9:17 am, George Dishman wrote:

"jacob navia" wrote in message


...
What physical evidence we have that the CMB is not just
radiation coming from a diluted hydrogen cloud whose mean
temperature is 2.7K


I assume here the implied qualification: "post redshift"


I think Jacob meant the actual temperature of the gas.

and whose radius is (say) 20 billion
years?


The evidence is the observed Hubble red shift. Take
the cloud and divide it into thin spherical shells.
We see some light from each shell but more distant
shells are red shifted to a greater degree. If the
cloud is at a uniform temperature, we should see
the integral of the redshifted curves. Ned Wright
produced a similar curve based on the CMBR being
red shifted starlight to illustrate the problem:


http://www.astro.ucla.edu/~wright/Stolmar_Errors.html


And if we were in the middle of such a HUGE cloud?


Yes, we would have to be at the centre, but the
model only works if the temperature is proportional
to the radius from us so that the redshifted
temperature is 2.7K for all shells.


Absolutely. This is the crux of the matter.

The cloud has
to have a spherically symmetric temperature profile


And what is wrong with that? The same is true, in essence, within
classical BB theory, for increasing z, no matter what cosmological
parameters you choose.


The difference is that Jacob was proposing a
gas cloud as an alternative to expansion,
essentially a steady-state cosmology.

with the lowest temperature of 0K at the centre,


Why?


The Hubble Law, redshift is proportional to
distance. If properly thought through it would
be more difficult because there are extra
factors of (1+z) in the standard model compared
to a steady state model but the point is that
a very specific temperature profile is needed
if we are to measure a Planck curve in all
directions. The dipole moment might be
explainable as uot position being offset from
the centre but even that might not work out.

exactly where our galaxy is situated, but the
temperature 13.7 billion light years away is 3000K.


And that would be just *one* of the explanations for the
CMB that doesn't require a big bang or a "beginning".


Why is this so hard for some people to accept?


xanthian.


Yes, why would that be so difficult to accept?


It is difficult to accept because there is no good
explanation for how a cloud could maintain such a
strange temperature profile without the gas at the
centre being warmed to equilibrium,


Expansion and accelerating expansion potentially account for that.


It is a given of Jacob's suggestion that there is no
expansion since he is offering it as an alternative.

Otherwise you are essentially re-introducing Olber's paradox at a
lower EM frequency range.


Yes, the cloud should reach equilibrium given
sufficient time, or alternatively the cloud
should cool from the outside and we should see
a high temperature here in the middle further
exagerrated by the redshifting of the radiation
from the distant edges of the cloud if they are
observable.

Incidentally, what, precisely, is the z/T relationship predicted by
EFE? (I honestly don't remember)


The intensity is proportional to (1+z)^4 which
maintains the black body curve. Of those, some
of the factors come from relativistic effects
but offhand I can't remember either. Look up
the Tolman Test for more on that, I think Ned
Wright had a page mentioning it.

and personally
I find the idea that the universe is centred on the
Earth even more distasteful than a beginning with a
homogenous and isotropic universe.


AHA! Back to the foundations of natural philosophy, I am pleased to
see!


Just pointing out that argument from philosophy
wasn't in favour of Jacob's proposal any more
than the Big Bang.

It has been pointed out (by prior authors) that Einstein's
general principle (also attributed {by some} to Galileo), puts the cat
amongst the pigeons in this respect. Stated pregeometrically, all
bodies of ref. are equiv. for formulating general laws of nature.
Hence coordinates centred around the observer are as good as any
other.


Or to state that the other way round, all other
coordinates are as good as the observer's.

Thus, the pre-Copernican and Copernican approaches are
equivalently valid in this relativistic respect. This is the "sting in
the tail" of GR theory, and greater authors than me have made this
point before.


What was that point again? ;-)

George
  #10  
Old June 27th 07, 01:52 PM posted to sci.astro.research
[email protected]
external usenet poster
 
Posts: 96
Default Quasar found 13 billion years away

On 26 Jun, 10:35, Chalky wrote:
.....
You have thus missed my real point, which is as follows:

Closer to us than the surface of last scattering, we should 'see'
successively closer shells of successively cooler gas, which should
emit thermal radiation, according to temperature. However, if the
temperature increases with redshift, and that radiation is, by
definition, redshifted by that redshift, all successive shells should
reinforce a black body 2.7K spectrum, when measured in the here and
now.


Rephrase it slightly - after correction for
the red shift, more distant neutral hydrogen
clouds, which were essentially in equilibrium
with the apparent temperature of the CMBR to
which they were exposed, should have higher
temperatures.

In fact that has been observed.

George
 




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