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Nothing about dark energy in the abstract. It is about redshift of galaxy analysis. Similarly the evidence that implies “dark energy” or “accelerated expansion” is due to redshift anomaly. I often wondered if the data is corroborated by other “standard candles” than type 1A, and if not, how reliable are type 1A SN truly?
ABSTRACT: "Observations have found black holes spanning 10 orders of magnitude in mass across most of cosmic history. The Kerr black hole solution is, however, provisional as its behavior at infinity is incompatible with an expanding universe. Black hole models with realistic behavior at infinity predict that the gravitating mass of a black hole can increase with the expansion of the universe independently of accretion or mergers, in a manner that depends on the black hole's interior solution. We test this prediction by considering the growth of supermassive black holes in elliptical galaxies over 0 < z ≲ 2.5. We find evidence for cosmologically coupled mass growth among these black holes, with zero cosmological coupling excluded at 99.98% confidence. The redshift dependence of the mass growth implies that, at z ≲ 7, black holes contribute an effectively constant cosmological energy density to Friedmann's equations. The continuity equation then requires that black holes contribute cosmologically as vacuum energy. We further show that black hole production from the cosmic star formation history gives the value of ΩΛ measured by Planck while being consistent with constraints from massive compact halo objects. We thus propose that stellar remnant black holes are the astrophysical origin of dark energy, explaining the onset of accelerating expansion at z ∼ 0.7."
with constraints from massive compact halo objects. We thus propose that stellar remnant black holes are the astrophysical origin of dark energy, explaining the onset of accelerating expansion at z ∼ 0.7."
Got it. Macho constraints (these were dark matter candidates too, though too few based on transit data). So there then is the “kick start” that appears in the historical Super Nova data, and I guess, because this contribution is so minuscule, (stellar mass black holes being so small compared to the Super Massive ones), the cosmo constant insanely weird tiny value (10 to the -120 smaller than Planck or something ridiculously tiny), it would make sense the contribution is from a small source creating the negative pressure observed.
We still need the mechanism (why not that they feed on the invisible dark matter then?).
Right. But as I said, and she is ignoring, the einstein equation implies that the constant is balancing the books. But what the super nova data showed, which was surprising to everyone and still on the table, that after inflation stops, everything is expanding as normal, but suddenly there is a “kick start” and the acceleration begins. The new paper has found precise correlation between the kick start epoc onwards, accounted for by the stellar mass black holes (that did not exist before, but form due to stellar evolution), and the very precise yet tiny increase in expansion. Sabine thinks the correlation is “too good do be true” so to speak. And of course there is no mechanism understood yet that would explain how the growth and expansion are directly related.
I don't know what she is on about; they have a whole section - 3.2 - and Appendices and Figure 2 working out whether the described black holes with non-singular vacuum-energy interiors can account for all the 'dark energy' and conclude that they can.
I don't know what she is on about; they have a whole section - 3.2 - and Appendices and Figure 2 working out whether the described black holes with non-singular vacuum-energy interiors can account for all the 'dark energy' and conclude that they can.
Actually this lady knows more about it as an expert on Super massive black hole growth. 31:50
Actually this lady knows more about it as an expert on Super massive black hole growth. 31:50
Her main counter-argument seems to be in fact confirming that Farrah et al.'s finding is significant.
While, once formed, elliptical galaxies ( EGs) are "passive", making them great candidates for this kind of research, she says that Farrah et al. did not consider, in the construction of their "time sequence" made of observed EGs at various ages by redshift, that EGs formed in the early universe would essentially grow less before forming as an EG compared to more recently formed EGs because the young universe was structured differently:
"in the early Universe those galaxies are probably going to be a lot smaller very chaotic whereas it later on in the universe they've probably settled down into disc galaxies with spiral arms that can funnel material along them and grow the black hole before they merge together with something else and eventually form the elliptical galaxy"
She is saying this in arguing that the apparent result in Farrah (growth in mass relative to stellar mass by a factor of 8 to 20 with EG age) may be due to a difference in how EGs are formed depending on whether they were formed long time ago (early universe) versus later on.
But the ones formed in the early universe would be the ones that now would have the largest redshift i.e. be the oldest ones in the Farrah sequence, and vice versa. And yet, it is these older ones (formed in the younger universe) that show the biggest mass gain, factor of 20, compared to the younger ones (which should grow more according to her) that show a factor of 8.
So, I don't understand how the differential growth histories before forming as an elliptical galaxy are supposed to be an alternative explanation of the Farrah findings - the effect of that would be running the other way in terms of mass growth factor, so Farrah should not have found an increase from 8 to 20 with age; and yet they did.
But the ones formed in the early universe would be the ones that now would have the largest redshift i.e. be the oldest ones in the Farrah sequence, and vice versa. And yet, it is these older ones (formed in the younger universe) that show the biggest mass gain, factor of 20, compared to the younger ones (which should grow more according to her) that show a factor of 8.
So, hmm. I think that is backwards…time does not run backwards. That would imply a DECREASE in mass as time moves forward anyway. Looking back means “long ago” or “old now”, but the things we see there are evolutionarily “young” compared to things we see nearby. The idea is that YOUNGER FROM OUR PERSPECTIVE high red shift ellipticals show lower masses than low red shift galaxies (nearby evolved OLD GALAXIES), assuming the ellipticals at ANY POINT IN TIME, don’t have material around them to evolve more, so consider/assume each one an evolutionary cul-de-sac. Since they are not mapping the literal time evolution, but infer that all other formational aspects were equal, they see GROWTH over time, not the opposite, so the younger ones will have grown more mass BY NOW, but that info has not reached us yet…it is inferred by the study. (If I have this wrong then I understand absolutely NOTHING )
She is saying that the assumption that the closer (older and more evolved) black holes that show growth via a mechanism OTHER than merger (elipticals don’t’ exist or evolve alone, they are ALL after-merger constructions), is ALREADY WELL KNOWN, but these mechanisms are NUMEROUS, and not clearly understood, and Farrah’s findings are just more of this non-merger growth on the huge pile.
Anyway, a lot of this is beside the point that it is the STELLAR MASS black holes appearance in the evolution of star formation that triggers the acceleration, i.e., more recently in history. At least that is THE important correlation the explains observations known since 1998. But as you know “correlation does not equal causation”.
Oh I see, calling EGs formed in the early universe 'old' was confusing.
Perhaps not ironically, a few days ago, James Webb found 6 EG’s too massive to be allowed to exist THAT EARLY in the Universe. In other words, they imply that actually….they are the equivalent of “OLD” EGs after all. First thoughts are that the universe is quite a bit older than 13.8 billion, in order for the amount of time needed to pass for galaxy merger and evolution on that scale to occur. However, as Hossenfelder points out, this is actually a PREDICTION of the alternative solution to Dark Matter Wimps/Machos, called MOND (Modified Newtonian dynamics). I believe if this theory ends up having legs after all, then “red shift” studies like the blackholes over time thing, might also need updating.
This guy says the 98% confidence regarding the coupling is actually a red flag. He traces the concepts through some other papers not mentioned earlier.
Not made obvious in years past when we had our very first views of some of these Supermassive black hole event horizons, is the fact that their construction due to mergers and basic “feeding” on gas, dust, and plasma, is extremely improbable on the timescales we know they must have formed. In other words we know they are single objects now via direct evidence, and JWST shows they were already formed in the early years, so that means we don’t understand how they are formed at all, because enough time has not elapsed to form them based on conventional means. A new idea about it here:
I know exactly what you mean. This same exact question has been bothering me for some time. It never seems to get addressed in the popular books or talks I listen to in enough detail. But I THINK I have some idea about why the Graviton “has to” exist... and that is because of Quantum Field Theory. If you make the other forces like Electromagnetism a field that lives in space, and you must quantize that force, then the logic follows that space itself gets quantized too in the process. Now everything in the world must happen in discrete chunks of vomit soup. This of course caused all kinds of issues in the process like vacuum energy discrepancies that have to be normalized and how to deal with gravity.
If space is quantized and the sun were to be blown up by aliens then the gravitational wave would propagate like a series of graviton dominos, because space is not a continuous medium according to QFT.
Dark matter was thought to be a possible GR/gravity problem but now there is enough evidence that points to it being a particle. Those that still hang on to GR have to alter the rules so much that it falls apart in other basic areas.
This post was in response to me back on page 18. Since then I recently learned two important concepts.
1. Grand Unification theories, or GUT, actually never worked and were falsified and given up on a year after the Standard Model become clear (1973-4). I realized it is the string theory guys in popular media reviving them, though dead in the water, to explain that story of how a quantized graviton would allow a TOE (theory of everything), as if the GUT was legitimate when it actually NEVER WAS. Meaning Electroweak does NOT unify with Strong Nuclear force at high energies…the biggest evidence being the Protons should show historic decay in experiments and simply do NOT.
This guy explains it all very well and MIGHT have a new idea that works
And 2. Like I was saying all along, why the heck must we quantize gravity, as it is not a real “force” but a curvature? And there is apparently work in explaining why we don’t need discrete Spacetime “force” carriers at all, and that quantum wave collapse is emergent.
For those members of the Foro in the US who maintain an interest in the Cosmos and Quantum Physics, tonight at 9:00pm on PBS, NOVA presents a program on quantum entanglement, the phenomenon where two subatomic particles mirror changes in each other instantaneously over any distance, even billions and billions of light years apart. Einstein called it "Spooky action at a distance."
Should be interesting for those of us left who used to have interesting discussions about such phenomena.
Bill
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And the end of the fight is a tombstone white, With the name of the late deceased, And the epitaph drear, "A fool lies here, Who tried to hustle the East."
Thanks Bill. Honestly, I came to terms recently with this misconception I have had for years. In video below “even physicists get this wrong”. No, Einstein never meant this about Entanglement, rather, his concern was with SUPER POSITION. Entanglemeant is actually like DOUBLE spooky action at a distance (4 possible states for two particles, both in superpositions). In the end I understand it as a statistical discrepancy in favor of correlation prediction (not a 100% guarantee regarding the future of one superposition after measuring the other. Like two spinning coins….you slap one down and predict the other to good % better than 50/50 as in real coins). The predictability is thought to be a “cheat” or short cut, but in the end no real practical applications (for example “teleportation” of photons does very little for us ).
I will say I am interested in microtubules in the brain that have shown a potential to hold superposition AKA quantum effects inside the squishy wet human brain (Hammerhoff/Penrose Orch OR), which was a shock for all those skeptics. Again, what good is it if it is true? They realize how the anesthetic drugs affect them like an “on off” switch for consciousness, so perhaps there could be a future for AI consciousness.
But her practical take on Entanglement below is a good way to orient yourself before watching other discussions about the Entanglement thing.
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