[ExI] How the James Webb telescope is reshaping cosmology

BillK pharos at gmail.com
Fri Dec 16 15:10:23 UTC 2022


On Fri, 16 Dec 2022 at 14:05, spike jones via extropy-chat
<extropy-chat at lists.extropy.org> wrote:
>
> Thx BillK.  The astronomy world has been buzzing about this.  I can't get my head around it.  I don't understand how galaxies could have formed that quickly, or why they woulda, for that would suggest a nonuniformity in density which isn't explained well by the current standard big bang/inflation model.  I haven't been able to understand why there would be any non-uniformity at all.
>
> But then we received that astonishing result from COBE in the 1990s which proved to us the anisotropy is real.  Later instruments verified it in greater resolution.  It's been 30 years and I still don't understand why that anisotropy is there or how it formed.
>
> spike
> _______________________________________________


Oh, you should just have asked!  :)

To convince yourself you will need to do a bit of reading, but the summary is -

The quantum fluctuations that occur during inflation get stretched
across the Universe and when inflation ends, they become density
fluctuations. This leads, over time, to the large-scale structure in
the Universe today, as well as the fluctuations in temperature
observed in the CMB.
Additionally, gravitational wave imperfections and angular momentum
fluctuations are created as well, but the latter decay as the Universe expands.
---------

You will immediately reply 'What quantum fluctuations?' -
That's where the further reading comes in. :)

Search for 'primordial fluctuations' or 'early density fluctuations'.
<https://www.esa.int/Science_Exploration/Space_Science/Planck/History_of_cosmic_structure_formation>
<https://bigthink.com/starts-with-a-bang/big-bang-meaning/>
should help.



BillK



More information about the extropy-chat mailing list