Scientists unveil largest 3D map of the universe ever

rod

Oct 22, 2019
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An interesting 3D map presented with differences for the H0 or the Hubble constant too. EBOSS estimated the Hubble constant, 67.4 and 69.0 km/s/Mpc. Others like Freedman noted this difference. "Freedman also notes that the disagreement over the Hubble constant depends to some extent on what methods are used. She herself has done studies using Cepheid variable stars and red giant stars, which give two different results. “I think we still don't know how this issue will be resolved,” she adds. “It is an interesting time in cosmology.”, ref - https://skyandtelescope.org/astronomy-news/new-3d-map-universe-growing-cosmological-debate/

Using this cosmology calculator, http://www.astro.ucla.edu/~wright/CosmoCalc.html, the Hubble time using z = 67.4 is 14.168E+9 years ago for the age of the universe. Using z=69, Hubble time is 13.84E+9 years ago. There is 3.28E+8 years time difference (delta) between these two values for the Hubble time that could change much in the BB cosmology for timelines, e.g. origin of the CMBR and earlier conditions, e.g. inflation. Freedman et al also report other H0 values, some range up to 82 km/s/Mpc. NASA ADS Abstract, 'The Completed SDSS-IV Extended Baryon Oscillation Spectroscopic Survey: Growth rate of structure measurement from cosmic voids', https://ui.adsabs.harvard.edu/abs/2020arXiv200709013A/abstract, July 2020. The arxiv report is attached in this record. The redshift range surveyed is, "eBOSS conducted a 5-year observation program, surveying the large scale structure of the Universe over a redshift range from 0.6 to 3.5." That is some range of redshifts surveyed and SDSS also reported cosmic high-noon for star formation rates too. The early universe according to BB cosmology, created SMBHs, PBHs, star formation rates much faster and higher than anything we see today (e.g. QSO or quasar formations, Population III stars) in astronomy. The universe is running downhill, not uphill and winding down as the universe expands. Processes observed operating today in astronomy are not the same as the early universe in BB cosmology (e.g. inflation, BBN, PBH forming, SMBH forming, quasars forming, Population III stars forming).
 
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Being an integrative cosmological summary based on the baryonic acoustic oscillations and the cosmic microwave background to establish flatness it reinforce the standard model nicely.

The structure data in the survey strongly fit dark matter evolving according to general relativity. The flatness of space is now 10^-4 – yielding a universe volume at least 100 million times larger than the observable – which is just an order of magnitude from the detection limit.

Dark energy can be detected at 8 sigma based on accepting flatness, it is constant and yields a current expansion rate at H0 = 68.20 +/- 0,81 km s^-1 Mpc^-1 which likely means no physics (< 72 km s^-1 Mpc^-1 at nearly 3 sigma) and is consistent with simplest anthropic finetuning which they point out as possible and substantially strengthened explanation.

"Nevertheless, the observed consistency with flat ΛCDM at the higher precision of this work points increasingly towards a pure cosmological constant solution, for example, as would be produced by a vacuum energy finetuned to have a small value. This fine-tuning represents a theoretical difficulty without any agreed-upon resolution and one that may not be resolvable through fundamental physics considerations alone (Weinberg 1989; Brax & Valageas 2019). This difficulty has been substantially sharpened by the observations presented here."
 

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