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New Evidence Against the Standard Model of Cosmology

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Re: New Evidence Against the Standard Model of Cosmology

#41

Post by EGreg »

beeboop wrote: post #20
evgen wrote: post #18

Earlier quoted context omitted.

> the c10l principle Don't do this. It is bad enough that every major devops/infra component needs to create some tag, but dropping it in to random places is worse than the regular backronyms and cute project names science and tech people use to try to hide complexity. It just adds confusion for no rhyme or reason other than trying to sound like you are a part of some club of insiders.

You see it everywhere really. Military and politicians and government orgs all do it to embarrassing lengths too

They also call things polintelcom and codenames like eschelon and prism, doesnt mean it’s great practice for us

Btw ESCHELON and Five Eyes coordination existed for so long and people only woke up when Snowden revealed prism

Re: New Evidence Against the Standard Model of Cosmology

#42

Post by kkylin »

zeven7 wrote: post #35
Svoka wrote: post #16

Earlier quoted context omitted.

That would be true if young scientists wouldn’t continuously make successful predictions based on cosmological principle among other observable effects of the general relativity and standard model. Make observable prediction, coherent thesis, then we’ll talk. Of course our models are not perfect, but it is best we have. Physics so far never dealt in “fundamental truths”, just good enough models. So far, this is best…

I'd argue that Einstein in particular cared a lot about "fundamental truths". Not everyone can be Einstein, but I'm glad some people care about asking deeper questions.

I don't disagree with your point, but do want to add that not publishing on "fundamental truths" isn't the same as not asking those questions. Not everyone's going to have something novel, plausible, and fundamental to say on a regular basis, hence most publications (even if everyone's asking these questions, which granted they're probably not) are going to be much more incremental.

Re: New Evidence Against the Standard Model of Cosmology

#43

Post by sahil50 »

zozbot234 wrote: post #40
drran wrote: post #29

Earlier quoted context omitted.

As opposed to one of "tired light" models. Light is not immortal, so it loses some energy with time. E.g. gravitational noise can affect photon energy, or photon can lose some energy to medium due to friction, or photon can lose some energy because of truncation of ideal sinusoidal wave at Planck scale, or speed of light is a bit slower than c (because light arrived 16 seconds later than gravitational waves, when gra…

The standard argument against 'tired light' is that it should lead to scattering of light from more distant objects, but this has not been observed in the data.

The standard argument is a straw man argument. Tired light is not photons getting scattered, and is not photons bumping into stray electrons.

Tired light is because there is a cost to traveling through spacetime. The photon is warping the shape of all the universe mass around it. The photon is doing work.

Re: New Evidence Against the Standard Model of Cosmology

#44

Post by naasking »

sahil50 wrote: post #34
FridayoLeary wrote: post #17

Earlier quoted context omitted.

could you pls elaborate on that?

What Hubble objectively measured wasn't galaxies receding. He measured redshift. Or photon energy loss. And there's another way to explain this, that is simpler, self-consistent, and doesn't require the concept of "inflation" where apparently space expanded faster than the speed of light. The explanation: photon hubbling, tired light. That galaxies are frankly right where they are. They're not receding. The photon lo…

"Tired light" has failed other tests, so it's probably not the answer.

Re: New Evidence Against the Standard Model of Cosmology

#45

Post by sahil50 »

naasking wrote: post #44
sahil50 wrote: post #34

Earlier quoted context omitted.

What Hubble objectively measured wasn't galaxies receding. He measured redshift. Or photon energy loss. And there's another way to explain this, that is simpler, self-consistent, and doesn't require the concept of "inflation" where apparently space expanded faster than the speed of light. The explanation: photon hubbling, tired light. That galaxies are frankly right where they are. They're not receding. The photon lo…

"Tired light" has failed other tests, so it's probably not the answer.

How so?

Considering all the data on redshift we have, tired light fits. Not galactic recession.

Rough calculations https://docs.google.com/spreadsheets/d/1HI61-pDIzzSItw48K0ga...

Data from https://ned.ipac.caltech.edu/Library/Distances/

Re: New Evidence Against the Standard Model of Cosmology

#46

Post by tlogan »

shmageggy wrote: post #19

Any time dissenting physics/astronomy opinions show up on here, it's always Sabine Hossenfelder. Is she a lone wolf or the face of a larger community?

She might be right but, as of now, the evidence shows that she is probably not right.

But as with everything, contrarian point of view is always popular on the internet. And we all want be in the know (have some secret knowledge) thus posts like this are popular.

So if she is really right we will feel like winners - if not, who cares: it is internet.

Re: New Evidence Against the Standard Model of Cosmology

#47

Post by rich_sasha »

teilo wrote: post #23
rich_sasha wrote: post #3

Not knowing much about the subject: cosmological principle appears to say that laws of physics are uniform in space. Then, with known matter and forces, this leads to some structure, with fluctuations, and hence some scale over which matter is uniformly distributed. If we calculate such a scale and find matter is still not uniform at that scale, wouldn’t the first conclusion be that there are missing terms in either…

> Rather than saying that laws of physics are not space-homogeneous. No one is saying that, and if the cosmological principle falls, it does not imply that in the least. It just means we need to revisit our assumptions about things like hyperinflation, dark matter, etc. Even more exciting, it may mean we need to look for the remnants of a force active during the initial inflation of the universe, that can account for…

Hmm, but if the principle comes with a model-dependent length scale, that experimentally looks wrong, why should I discard the principle when it might as well be an incomplete model?

Or frankly inaccurate estimation, my understanding is that it is extremely hard to actually sully simulate the lambda-CDM model from Big Bang.

Re: New Evidence Against the Standard Model of Cosmology

#49

Post by sharpener »

sahil50 wrote: post #38
mkl wrote: post #30

Earlier quoted context omitted.

What does that mean in this context? How does it relate to the cosmological principle in the article?

Hubble's constant is related to all the other fundamental constants. And is not a measure of "expansion", which is one of the core ideas of the Standard Model. Relation to the cosmological principle: self-similarity not just in terms of density and homogeneity, but also macro and micro scales. H, a measure of cosmic stuff, is literally derivable from atomic stuff.

I'm not a cosmologist but...

Is it possible to have both photon tiring and expansion and still measure the same numbers in experiment?

Also wouldn't the arc separation of deep field stars increase detectably with expansion?

Re: New Evidence Against the Standard Model of Cosmology

#50

Post by whatshisface »

rich_sasha wrote: post #5
JetSetWilly wrote: post #2

> Two years ago, I told you about a paper by Subir Sarkar and his colleagues, that showed if one analyses the supernovae data correctly, without assuming that the cosmological principle holds on too short distances, then the evidence for dark energy disappears. That paper has been almost entirely ignored by other scientists. Is this a case of science advancing one funeral at a time? We have to wait for the dark energ…

There is more evidence for dark energy. Discrepancies in redshift vs distance are just one, and there are interestingly also other explanations for it. IIRC in lambda-CDM, if you don’t have dark energy, the whole universe just looks very different, eg the structures of galaxies, groups and supergroups etc are not the same. It might still be wrong, but more nails are needed for this coffin.

One thing that can happen when you are doing computer modeling to find the input parameters that explain your observations is getting stuck in a local maximum. I am absolutely ready to believe that eliminating dark energy from current models makes their results look less like the real universe, but the number of re-runs that would be required to sample the entire parameter space and demonstrate that there were no other parameterizations that looked like our universe would be enormous, and if you include the possibility of new theories, infinite.

There would either have to be some kind of theoretical reason to think that the best known parameterization of a simulated lambda-CDM universe is not merely a local maximum, or the parameters would have to be well-constrained, by observations, so that the free parameter space was small enough to exhaustively explore. I am not aware of either condition being true so I will express some skepticism about the conclusions from the models. Nonetheless, my lack of knowledge about those conditions is not very strong evidence for their absence, and I know there could be someone reading this and feeling very annoyed that I don't know about the Backhausen-Thule principle, or whatever piece completes this puzzle. (Your contribution to the discussion, oh annoyed reader, would be greatly appreciated.)

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