- Nov 11, 2019
Well, as I note in my comment on the article, it already is (as you later note) but the superfluid physics here is not relevant to our universe ...What if spacetime of our whole universe is a certain kind of superfluid?
... so this is a side topic.The problem is how GR emerges from QM! Which is actually, how spacetime emerges from quantum vacuum!
Again, the paper and the article is not about our universe, despite the click bait title - you likely did not read either and is not interested in the presented science.Apparently helium 3 and helium 4 cannot freeze even at absolute zero kelvin - if this is true then the universe will always have motion and cannot go back to a static motionless state from now on.
I'm not sure what "started to fall" means, though it is true that a classical newtonian gravity model of the expansion derives it as analogous to a thrown mass (for the matter dominated era), c.f. cosmologist Susskind's cosmology lectures at Stanford's open web courses.When the Universe started to fall:
The Gravitational Instability Cosmological Theory on the Formation of the Universe. The Theory: (1) The expansion of the universe is a result of the " heat ' contained therein;
(2) The source of the " heat " is the cosmic microwave radiation background at 3 kelvin,
(3) The microwave electro magnetic-nuclear energy was formed as a result of the
interaction of two different static gravitational vacuum fields, causing gravitational
No, it obviously isn't [ https://en.wikipedia.org/wiki/Big_Bang ].That is a summary of the Big Bang Theory. Actually the universe if hot at 3 kelvin for the billion ly + size of it 3 kelvin is impressive. The CERN collider operates at 2 kelvin, my question is when was the last time the universe was at 2 kelvin ? ( Some Big Bang theorist would say never. )
That link, if not the description, takes me to a pseudoscience site, with superstition thrown in for good measure.Here is a completely different cosmological theory
Again, the paper and the article is not about our universe, despite the click bait title - you likely did not read either and is not interested in the presented science.
A quantum particle field, as all the universe forces and matter seem to be constituted of, have always fluctuations even if a perfect vacuum [https://en.wikipedia.org/wiki/Vacuum_state ].
I'm not sure what "started to fall" means, though it is true that a classical newtonian gravity model of the expansion derives it as analogous to a thrown mass (for the matter dominated era), c.f. cosmologist Susskind's cosmology lectures at Stanford's open web courses.
That leads up to that the expansion scale factor as a function of time develops depending on the inner energy state of the universe [ https://en.wikipedia.org/wiki/Scale_factor_(cosmology) ; note that the matter dominated era scale factor alpha(t) ~ t^2/3 describes precisely a parabola of a thrown mass].
The radiation dominated era between the hot big bang start and about 50 kyrs, until dilution made the universe enter the matter dominated era for a couple of billion years (we are now in the dark energy dominated era) could be said to be driven by the universe "heat" at temperatures ranging from close to Planck temperature down trending towards the ~ 3,000 K when cosmic background radiation was released at ~ 400 kyrs. (Which now with space expanded by a factor ~ 1,000 has stretched cosmic background photons to a radiation temperature of ~ 3 K.)
That is far from your quantitative description, and any correspondence with reality stops there. E.g. there is only one type of gravity field.
No, it obviously isn't [ https://en.wikipedia.org/wiki/Big_Bang ].
And it is better described today as inflationary hot big bang cosmology [View: https://www.youtube.com/watch?v=P1Q8tS-9hYo
; the manuscript source is the popular astrophysicist Katie Mack]. One of the reasons for that is how the inflation that precedes the hot big bang period explains both the flatness and the homogeneity and isotropy of space, which only an expansion cannot [see the video].
The universe has never before been at 2.7 K, obviously.
That link, if not the description, takes me to a pseudoscience site, with superstition thrown in for good measure.
So no, it isn't "a theory" at a guess. Even if there were some reasonable numbers in a meaningless attempt at quantification of the absurd. it couldn't be published (hence the site).
[Reposting pseudoscience + superstition site text using crackpot font.]
[Reposting a BEC reference from Wikipedia.]
When you references to specific quotes, you may want to use the full reference ("fall into the lowest accessible quantum state") and add the quote. But our universe is obviously not a condensate nor at a lowest accessible state, as evidenced by us writing this.When the universe started to fall; fall in this case means the following:
quote : " Einstein proposed that cooling bosonic atoms to a very low temperature would cause them to fall (or "condense") into the lowest accessible quantum state, resulting in a new form of matter. "
The clickbait title in no way refer to our universe. The simplest general relativistic model both has the observed universal speed limit and an ideal "fluid" which in a classic model is an interaction free ideal "gas". These are different things, which the observation of having particle isolation at walls in order to exceed the Landau velocity (the speed at which fluid excitations would attain negative energy).
So it is a curious, but not breaking physics of superfluids or the universe.
I know the thread has long comments, but in my first I noted that this model is not applicable to our universe.
Thank you, and thank you for an interesting, detailed and thoughtful comment!I must agree with the comments made by Mr. Larsson.
[ https://www.sciencemag.org/news/2020/06/galaxy-s-brightest-explosions-go-nuclear-unexpected-trigger-pairs-dead-stars ]But he thinks cosmologists will run into trouble as they put their theories to more rigorous tests that require more precise standard candles. “Supernovae could be less useful for precision cosmology,” he says.
Astronomers already knew the peak brightness of type Ia supernovae isn’t perfectly consistent. To cope, they have worked out an empirical formula, known as the Phillips relation, that links peak brightness to the rate at which the light fades: Flashes that decay slowly are overall brighter than those that fade quickly. But more than 30% of type Ia supernovae stray far from the Phillips relation. Perhaps low-mass D6 explosions can explain these oddballs, Shen says. For now, those who wield the cosmic yardstick will need to “throw away anything that looks weird,” Gaensicke says, and hope for the best.
[ https://arxiv.org/abs/2007.08991 ]The inverse distance ladder measurement under this model yields H_0 = 68.20 ± 0.81 km s^-1Mpc^-1, remaining in tension with several direct determination methods; the BAO data allow Hubble constant estimates that are robust against the assumption of the cosmological model. In addition, the BAO data allow estimates of H_0 that are independent of the CMB data, with similar central values and precision under a ΛCDM model.
[ https://www.sciencedaily.com/releases/2021/01/210104131925.htm ]”Now we’ve come up with an answer where Planck and ACT agree,” said Simone Aiola, a researcher at the Flatiron Institute’s Center for Computational Astrophysics and first author of one of two papers. “It speaks to the fact that these difficult measurements are reliable."
[ https://arxiv.org/pdf/2007.07289.pdf ]ΛCDM is a good fit. The best-fit model has a reduced chi^2 of 1.07 (PTE=0.07) with H_0=67.9±1.5 km/s/Mpc.
Here we show that accounting for the enhanced recombination rate due to additional small-scale inhomogeneities in the baryon density may solve both the H_0 and the S_8 − Ω_m tensions. The additional baryon inhomogeneities can be induced by primordial magnetic fields present in the plasma prior to recombination. The required field strength to solve the Hubble tension is just what is needed to explain the existence of galactic, cluster, and extragalactic magnetic fields without relying on dynamo amplification.
[ https://arxiv.org/abs/2004.09487 ]Allowing for clumping using Model 1 makes the decisive difference, moving the best fit to H_0 = 71.03 ± 0.74 km s^-1 Mpc^-1 … This means that Planck+H3 M1 is essentially as good a fit to CMB as the Planck ΛCDM.
[ https://arxiv.org/pdf/2007.08991.pdf ]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.
[ http://articles.adsabs.harvard.edu/full/1992ARA&A..30..499C ; "The cosmological constant", Carroll, S. M., Press, W. H., & Turner, E. L., Journal: In: Annual review of astronomy and astrophysics. 1992].An interesting consequence of this argument is that Λ should not be zero, but only small enough for life to exist. Weinberg (1987, 1989) argues that this bound is very close to the observational limits. The prossibility that Λ is small for anthropic reasons is therefore of interest to astronomers, since they should be able to detect a nonvanishing value.