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Galaxy discovered at 420 Million years after the supposed "Bang"

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jacob navia

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Nov 16, 2012, 3:12:29 AM11/16/12
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NASA JPL published today a press release
http://www.jpl.nasa.gov/news/news.php?release=2012-360cid=release_2012-360

telling that Spitzer has discovered a tiny (600 light years across)
galaxy only 420 million years after the supposed "bang"... At z=11.

This means that after only 420 million years after the supposed "bang"
stars existed, galaxies could form, etc.

I know, I have been told that the galxies were already there as small
concentrations of matter in an otherwise smooth universe.

Anyway this will be over soon. If we find any element heavier than
helium in that galaxy the "bang" ends and we can start measuring our
ignorance.

Interesting times.

Hans Aberg

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Nov 16, 2012, 5:58:47 AM11/16/12
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On 2012/11/16 09:12, jacob navia wrote:
> NASA JPL published today a press release
> http://www.jpl.nasa.gov/news/news.php?release=2012-360cid=release_2012-360
>
> telling that Spitzer has discovered a tiny (600 light years across)
> galaxy only 420 million years after the supposed "bang"... At z=11.

There is a problem with the link. This one worked for me:
http://www.jpl.nasa.gov/news/news.php?release=2012-360

Hans

Phillip Helbig---undress to reply

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Nov 16, 2012, 4:13:12 PM11/16/12
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In article <mt2.0-29837...@hydra.herts.ac.uk>, jacob navia
<ja...@spamsink.net> writes:

> This means that after only 420 million years after the supposed "bang"
> stars existed, galaxies could form, etc.

Why is this surprising? A redshift of 11 means that the average density
was 11*11*11=1331 times higher than now. The average density now is
about a hydrogen atom per cubic meter, so back then it was about 1331
hydrogen atoms per cubic meter. Hardly dense enough to prevent the
formation of stars.

> I know, I have been told that the galxies were already there as small
> concentrations of matter in an otherwise smooth universe.

Right; this is completely expected. CDM is a bottom-up scenario of
structure formation.

> Anyway this will be over soon. If we find any element heavier than
> helium in that galaxy the "bang" ends and we can start measuring our
> ignorance.

Why so? Massive stars live for just a few million years, so some of
them could have gone supernova and produced heavy elements.

Eric Flesch

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Nov 16, 2012, 4:33:42 PM11/16/12
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On Fri, 16 Nov 12, Hans Aberg <haber...@telia.com> wrote:
>On 2012/11/16 09:12, jacob navia wrote:
>> NASA JPL published today a press release
>
>There is a problem with the link. This one worked for me:
> http://www.jpl.nasa.gov/news/news.php?release=2012-360

Or go straight to the paper:
http://arxiv.org/abs/1211.3663

Eric Flesch

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Nov 16, 2012, 4:40:49 PM11/16/12
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On Fri, 16 Nov 12, jacob navia <ja...@spamsink.net> wrote:
>telling that Spitzer has discovered a tiny (600 light years across)
>galaxy only 420 million years after the supposed "bang"... At z=11.

They get this size by comparison to the standard model projection, see
their figure 16 of arXiv:1211.3663. It is smaller than the curve
followed by the standard size. As usual, the 1/z model is not plotted
on the figure, and as usual, it would have fit the size of this galaxy
well.

They say the 1/z model has no physical analogue, but it does, just not
one that people are used to.

Eric

Steve Willner

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Nov 16, 2012, 4:50:14 PM11/16/12
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In article <mt2.0-29837...@hydra.herts.ac.uk>,
jacob navia <ja...@spamsink.net> writes:
Preprint at
http://xxx.lanl.gov/abs/1211.3663

> telling that Spitzer has discovered a tiny (600 light years across)
> galaxy only 420 million years after the supposed "bang"... At z=11.

Much as I love Spitzer, this is mainly a Hubble discovery. Spitzer
was important for ruling out some alternative interpretations (such
as local, dusty galaxies).

> This means that after only 420 million years after the supposed "bang"
> stars existed, galaxies could form, etc.

Right. The very first galaxies probably formed around age 250 Myr
(z=16), though nobody knows for sure.

> If we find any element heavier than
> helium in that galaxy the "bang" ends

Why would you think that? It takes rather less than 10 Myr for a
massive star to form, evolve, and explode as a supernova. Lots of
heavy elements are synthesized during the explosion and of course
spread far and wide.

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123 swil...@cfa.harvard.edu
Cambridge, MA 02138 USA

jacob navia

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Nov 17, 2012, 1:48:19 PM11/17/12
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Le 16/11/12 22:50, Steve Willner a ecrit :
>
>> If we find any element heavier than
>> helium in that galaxy the "bang" ends
>
> Why would you think that? It takes rather less than 10 Myr for a
> massive star to form, evolve, and explode as a supernova. Lots of
> heavy elements are synthesized during the explosion and of course
> spread far and wide.
>

Yes, a star can explode in 10 million years, but then... the elements
have to disperse into space, cool, condense, form a new star, etc.

That is surely far slower.

To affect the spectrum of a galaxy this process must be repeated
hundreds of times so that the elements in question make for an important
part of the galaxy.

All this in less than 420 million years?

Eric Gisse

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Nov 17, 2012, 3:01:08 PM11/17/12
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Why all the sarcasm quotes?

Every time you post one of these, the formation is a nonzero and nontrivial number after t=0. Nothing ever meaningfully challenges the concordance cosmology model.

Objects had to form some time. Do you have a particular reason as to why this is a problem, or is it just general personal dislike?

Phillip Helbig---undress to reply

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Nov 17, 2012, 3:02:06 PM11/17/12
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In article <mt2.0-8582...@hydra.herts.ac.uk>, Eric Flesch
<er...@flesch.org> writes:

> On Fri, 16 Nov 12, jacob navia <ja...@spamsink.net> wrote:
> >telling that Spitzer has discovered a tiny (600 light years across)
> >galaxy only 420 million years after the supposed "bang"... At z=11.
>
> They get this size by comparison to the standard model projection, see
> their figure 16 of arXiv:1211.3663. It is smaller than the curve
> followed by the standard size. As usual, the 1/z model is not plotted
> on the figure, and as usual, it would have fit the size of this galaxy
> well.

I haven't looked yet, but "standard model" probably assumes a completely
homogeneous universe. If the universe along the line of side (by chance
or due to some selection effect) is under-average in density, then the
angular size will also be smaller.

> They say the 1/z model has no physical analogue, but it does, just not
> one that people are used to.

And that is?

Eric Flesch

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Nov 18, 2012, 5:24:26 AM11/18/12
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On Sat, 17 Nov 12, Phillip Helbig wrote:
><er...@flesch.org> writes:
>> They say the 1/z model has no physical analogue, but it does, just not
>> one that people are used to.
>
>And that is?

Well, as an intro, an open question is what separates the past from
the present from the future. What characterizes "now" that keeps it
separate from the past? It's something not comprised of matter or
energy, yet a fundamental aspect which perhaps can be measured only
externally, and is invariant as seen from within the universe.

Consider "scale" as one such aspect. Scale has counter-intuitive
qualities such that one sphere (drawn in a vacuum) which is twice the
width of another, has a lesser surface-area-to-volume ratio, even
though in every other way they are identical. We can calculate this,
but it fails the common-sense test.

So, seeing that scale is something with real effect, let's suppose
that scale is quantifiable and that it isn't invariant, and that in
fact it doubles per each time T0 -- thus separating the past from the
present from the future, because of the migrating scale. Internally,
it makes no difference to us whatsoever except via look back so that
at z=1 we see the universe as it was T0 ago when things look half as
large, causing the redshift because the internally-consistent C looks
to us to be travelling at half the speed then.

Such a universe is seen by us to have an edge which is exactly twice
as far away as z=1, if we had some way to apply today's scale to it.
This model conserves isotropy as all places are the same, it is only
via look-back that we see the comparative change. And because of the
scale change directly dependent on z, and the fact that all places of
high z are seen by our local eyes to be at about the same distance, it
thus follows that angular size is directly proportional to z for
sufficiently high z -- above z=2 in particular.

So there is a self-consistent model, with angular size proportional to
z, and one that people are not used to. Perhaps J.B.S.Haldane ("the
universe is queerer that we can suppose") would have liked this
model.

cheers, Eric

Steve Willner

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Dec 18, 2012, 1:25:08 AM12/18/12
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SW> Why would you think that? It takes rather less than 10 Myr for a
SW> massive star to form, evolve, and explode as a supernova. Lots of
SW> heavy elements are synthesized during the explosion and of course
SW> spread far and wide.

In article <mt2.0-3213...@hydra.herts.ac.uk>,
jacob navia <ja...@spamsink.net> writes:
> Yes, a star can explode in 10 million years, but then... the elements
> have to disperse into space, cool, condense, form a new star, etc.

I suggest you put in some numbers. For "disperse into space,"
remember that 1 km/s is 1 pc/Myr. Cooling time is months to a few
years, depending on density. That's enough for heavy elements to be
detected in the gas phase, which is generally easier than detecting
them in stars.

We don't have a good theory of star formation and therefore don't
have a good estimate for "condense, form a new star." What we can
say is that with gas cooling from heavy elements and dust available,
the second generation of stars ought to take less time to form than
the first.

> To affect the spectrum of a galaxy this process must be repeated
> hundreds of times

Why hundreds of times? One massive SN ejects about 50 solar masses
of heavy elements. What do you think the mass of the early galaxies
is, and what metal abundance are you expecting?

> All this in less than 420 million years?

Seems like plenty of time to me.

Robert L. Oldershaw

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Dec 19, 2012, 4:35:24 AM12/19/12
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On Saturday, November 17, 2012 3:01:29 PM UTC-5, Eric Gisse wrote:

> Nothing ever meaningfully challenges the concordance cosmology model.
>

How true.
Not observations.
Not logical argument.

The thing is cast in stone and will rule forever.
All bow down and be humble.

[Mod. note: when I was a PhD student 20 years ago, the accepted
cosmology was very different from what's believed to be the case now.
And what changed it was -- observations and logical argument. Just
sayin'. -- mjh]

Eric Gisse

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Dec 20, 2012, 2:28:10 AM12/20/12
to
On Wednesday, December 19, 2012 3:35:24 AM UTC-6, Robert L. Oldershaw wrote:
> On Saturday, November 17, 2012 3:01:29 PM UTC-5, Eric Gisse wrote:
>
>
>
> > Nothing ever meaningfully challenges the concordance cosmology model.
>
> >
>
>
>
> How true.
>
> Not observations.
>
> Not logical argument.
>

[...]

What I actually said:

"Every time you post one of these, the formation is a nonzero and nontrivial number after t=0. Nothing ever meaningfully challenges the concordance cosmology model."
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