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Comment by gmane | Hacker News Reader

Sorry, the conclusion in the paper really underlies how poorly the results fit the evidence: "The resulting almost doubling in the age of the Universe and increasing the formation times by 1 order of magnitude has been a subject of concern and requires that the new model also explain some critical cosmological and astrophysical observations" [0]

Call me skeptical of the claims made.

[0] https://iopscience.iop.org/article/10.3847/1538-4357/ad1bc6#...

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It's a double edged sword. On the one hand the model helps to explain the "impossible early galaxy" problem (since the universe is older than we thought).

On the other hand, if the universe is older there are other things that will need more research to figure out.

You should be sceptical, but there is not as yet a reason to entirely reject it. I'm not really a fan of the tired light theories myself, but glad to see different ideas being explored.

Any article/paper claiming nonexistence of dark matter that does not mention the bullet cluster should be sent to the spam folder.

The bullet cluster is not the slam dunk proof of dark matter that is commonly supposed. For example, see this: https://tritonstation.com/2024/02/06/clusters-of-galaxies-ru...

>So the unseen mass in clusters could just be ordinary matter that does not happen to be in a form we can readily detect.

That is the same thing as dark matter...

No. Dark matter is a proposed form of matter which does not interact with light.

Normal matter we can't detect isn't dark matter - it's just currently undetected matter. As our observational ability improves we find more of it.

That's WIMPS, early candidates for dark matter included primordial black holes and dust.

WIMPS are most probably not real. They'll keep searching but it's quite unlikely they'll find any.

https://en.m.wikipedia.org/wiki/LZ_experiment

A good point. I have heard of primordial black holes as a candidate for (at least some) dark matter. Not heard that dust was ever a candidate (if you have a reference it would be appreciated).

Baryonic (tangible) dark matter exists in the form of MACHOs, which includes small cold planetary-mass dwarf stars. But there's a limited number of these, and the Big Bang hydrogen helium ratio puts limits on the amount of baryonic matter there can be.

Dark matter is a question, not a theory.

WIMPS, sterile neutrinos, SIDM, primordial blackholes, MACHO, MoND, entropic gravity, &c all seek to answer the black hole question.

I think there are too many unknowns and we are nowhere near close to fully understanding our universe that we should be open minded to new ideas and see if they fit into our understanding. Dark matter is one explanation to the bullet cluster but perhaps there is another we just don't understand. Yes if someone has a perpetual motion machine to the spam folder but I am always open to hear new ideas to our universe.

I assume you are referring to gravitational lensing estimates of total matter versus visible?

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