The conventional interpretation of the cosmic microwave background (CMB) anisotropies is that they represent the result of a primordial ‘minefield’ of Dirac-delta energy concentrations that has a characteristic comoving spatial distance between the mines. The mines all exploded at the time of the big bang, generating what evolved into spherical baryonic-matter pressure waves in the primordial plasma, and the time of recombination just happened to coincide with the time when the diameters of the pressure waves were approximately equal to the characteristic scale of the minefield. The observed CMB anisotropies are believed to reflect the spatial form of the universe’s matter at the time of recombination.
This concept appears to be purely speculative, with no underlying mechanism proposed for the existence and form of the ‘minefield’, other than generic allusions to quantum events.
Even if this conceptual model is valid, it doesn’t imply anything about the behavior of dark matter- dark matter doesn’t care about baryonic pressure gradients. A random field of dark matter particle concentrations would have initiated its gravitational collapse process as soon as the particles formed, presumably the time of baryogenesis. At that early time the universe was extremely small (and gravitational accelerations extremely rapid). The dark matter would have collapsed hierarchically: smaller dark matter concentrations would consolidate most rapidly, medium-sized concentrations would have taken longer to consolidate, and really-large scale concentrations would still be far from consolidated. The same process can be described as small voids forming initially, as particles were gravitationally drawn away from lower-density regions, and those small voids subsequently expanding and merging into ever-larger voids, eventually comprising inter-cluster space.
Initially, when the cosmic velocities of dark matter concentrations were small, the collapses would have been towards the centers of local regions of above-average dark matter density. These collapses would have led to the formation of black holes, comprised of dark matter, with a wide range of sizes. As time passed and medium-sized dark matter concentrations started to collapse, their components would have developed significant amounts of angular momentum. They would have collapsed into gravitationally-bound dynamic systems, the beginning of the cosmic web. Those systems would have contained both the first generation of black holes, still feeding, and substantial amounts of dark matter particles.
At any given point in time, the evolving cosmic web would have a characteristic scale, reflecting the overall progress of the gravitational collapse process. In general, voids smaller than the characteristic scale would be slowly growing and merging, but at larger scales there would not yet have been enough time for significant density changes and void-mergers to occur.
By the time of recombination, the evolving dark matter web would have been surrounded by local concentrations of baryonic matter, unable to collapse deeper into the web because of the primordial plasma’s pressure. However, in inter-cluster space the vacuum would have been almost perfect. Following recombination, the baryonic matter halos would have started to collapse gravitationally into the dark matter halos, and the baryonic matter would have tended to be drawn towards the largest dark matter black holes. Galaxies would start to form, and increasing angular momentum at all scales would stabilize the forms of both the dark matter web and of the galaxies and their contents.
This process is entirely different from the conventional model of massive and super-massive black holes: that they formed by the gradual consumption, by early post-recombination supernova-remnant black holes, of large numbers of stars, of other supernova-remnant black holes, and of competitors. In this model, there were no massive or super-massive black holes at the time of recombination. This conventional model is currently being challenged by the James Webb Space Telescope’s identification of numerous super-massive black holes at very high redshifts.
So, a proposition: that the current cosmic web of dark matter was largely complete by the time of recombination, and it included both dark matter particles and dark matter black holes of all sizes. The web has evolved further since then, with more of the dark matter more localized into sheets and filaments and super-massive black holes. The cosmic minefield, and the baryon acoustic oscillations, are illusions.
Dear Ronald Ian Miller
If we like the 2 universal conservation laws (energy and momentum), we have to reject the big-bang hypothesis although every change from one state to another state (the creation of matter by the basic quantum fields) must have had one of more start positions "somewhere in the universe".
So if we want to interpret the image above - the polarization of the CMBR - we can think about a small volume (big-bang hypothesis) or a volume that represents the present visible universe (a universe that represents the universal basic quantum fields).
If we choose the second one the visible polarization is caused by huge gravitational fields. But we don't measure the radiation of celestial bodies that existed some 13,8 billion years ago. But if these celestial bodies are black holes the image above corresponds with the radiation of Hydrogen atoms while there existed already large black holes ("primordial" black holes). Because black holes don't emit detectable electromagnetic radiation.
See: BICEP2 Collaboration (2016): “Keck ArrayVII: MATRIX BASED E/B SEPARATION APPLIED TO BICEP2 AND THE Keck Array” https://arxiv.org/pdf/1603.05976.pdf
So I reacted on your last sentences in relation to the proposed baryon acoustic oscillations.
With kind regards, Sydney
Dear Ronald Ian Miller Our universe with several billions of galaxies in moderate distance, where each galaxy host billions of solar systems like ours is not result of an accidental mechanical event of big bang, thus we must accept this fact, Our universe is a complete entity.
The reality is, our science doesn't recognize an atom as unit of the universe, it pursues mechanical atom (QM) with electron/proton, neutron...and baryon, which up to date none of them never been observed yet to this date,
On the other hand, black holes are just postulation, and prediction is not science to even discuss about it.
read some of my articles for more detail.
regards.
Dear Sydney Ernest Grimm . Thanks for your comment. I'm not familiar with the mechanism for the polarization of CMB light, but after reading your post, my initial reading about CMB polarization suggested the polarization might also be due to gradients in the baryonic plasma density just prior to recombination. That would make sense, as the plasma would have been clustered around the cosmic web, so there would have been a strong large-scale anisotropy.
But, as you indicated, gravitational fields can also directly cause polarization, though it sounds like that requires a rotating gravitational source.
Regards, Ronald
Dear Ronald Ian Miller
The problem with the big-bang hypothesis and the related solutions to keep the concept “reliable” is the violation of the universal conservation laws (expansion of the universe). That doesn’t mean that Dark matter doesn’t exist – it is observed for example in the ”El Cordo” galaxy cluster and the Bullet cluster. The question if the flat rotational curve of galaxies is also caused by Dark matter is not yet solved.
However, your topic about Dark matter in the early universe is related to the big-bang model. A model that is questioned by the JWST observations. For example the ΛCDM model doesn’t predict the existence of a robust high-redshift galaxy candidate at red shift z ≈ 10.32 (UHZ1).
See: “Evidence for heavy seed origin of early supermassive black holes from a z ∼ 10 X-ray quasar” by Akos Bogdan et all (sept. 2023) at arXiv.org.
Thus the title of your discussion is somewhat fuzzy because there is no clear description about the proposed physical nature of Dark matter and the reliability of the standard cosmological model. That is why I enclosed the image of the polarized CMBR because it is in line with the JWST observations of the existence of giant black holes at some 100 million years after the proposed start of the universe. By the way, “everything” rotates in the universe (particles, atoms, planets, stars, galaxies and... black holes too).
With kind regards, Sydney
Dear Sydney Ernest Grimm ,
You make a good point re the Big Bang hypothesis being unproven. I deliberately avoided that question in my introductory comments about dark matter- the only real assumptions are that the early universe was very hot, that as it cooled both normal and dark matter particles formed, and gravitational effects due to initial inhomogeneities then drove the formation of cosmic structure.
I thought that was a big enough scope, and a radical enough proposition, for an interesting discussion.
Best regards, Ronald
For anyone following, I have updated the introduction to this discussion, and posted the update as a preprint: Deleted research item The research item mentioned here has been deleted
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