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Galaxy discovered at 420 Million years after the supposed "Bang"
NASA JPL published today a press release
http://www.jpl.nasa.gov/news/news.ph...lease_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. |
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Galaxy discovered at 420 Million years after the supposed "Bang"
On 2012/11/16 09:12, jacob navia wrote:
NASA JPL published today a press release http://www.jpl.nasa.gov/news/news.ph...lease_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 |
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Galaxy discovered at 420 Million years after the supposed "Bang"
In article , jacob navia
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. |
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Galaxy discovered at 420 Million years after the supposed "Bang"
On Fri, 16 Nov 12, Hans Aberg 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 |
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Galaxy discovered at 420 Million years after the supposed "Bang"
On Fri, 16 Nov 12, jacob navia 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 |
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Galaxy discovered at 420 Million years after the supposed "Bang"
In article ,
jacob navia writes: NASA JPL published today a press release http://www.jpl.nasa.gov/news/news.ph...lease_2012-360 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 Cambridge, MA 02138 USA |
#7
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Galaxy discovered at 420 Million years after the supposed "Bang"
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? |
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Galaxy discovered at 420 Million years after the supposed "Bang"
On Friday, November 16, 2012 2:12:51 AM UTC-6, jacob navia wrote:
NASA JPL published today a press release http://www.jpl.nasa.gov/news/news.ph...lease_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. 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? |
#9
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Galaxy discovered at 420 Million years after the supposed "Bang"
In article , Eric Flesch
writes: On Fri, 16 Nov 12, jacob navia 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? |
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Galaxy discovered at 420 Million years after the supposed "Bang"
On Sat, 17 Nov 12, Phillip Helbig wrote:
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 |
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