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New research puts age of universe at 26.7 billion years, nearly twice as old as previously believed (phys.org)

submitted 1 year ago by L4s@lemmy.world to c/technology@lemmy.world

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New research puts age of universe at 26.7 billion years, nearly twice as old as previously believed::Our universe could be twice as old as current estimates, according to a new study that challenges the dominant cosmological model and sheds new light on the so-called "impossible early galaxy problem."

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[–] ProcurementCat@feddit.de 99 points 1 year ago* (last edited 1 year ago) (3 children)

many scientists have been puzzled by the existence of stars like the Methuselah that appear to be older than the estimated age of our universe

No, not really, because the age of that star is compatible with the age of the universe within the error bars.

These galaxies, existing a mere 300 million years or so after the Big Bang, appear to have a level of maturity and mass typically associated with billions of years of cosmic evolution.

Galaxy formation is still an active area of research und different models predict different evolutionary rates

Instead, he proposes a constant that accounts for the evolution of the coupling constants.

That's exactly what Brans-Dicke theory is trying to do, and other modified theories of gravitation as well. Yet they can't explain stuff so well as Lambda CDM can.

Overall, tired light pretty much doesn't work well explaining the perfect black body behavior of the cosmic microwave background or surface brightnesses of galaxies.

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

[–] kescusay@lemmy.world 30 points 1 year ago (1 children)

Yeah, I'm not convinced, either. It seems like every couple of years, someone puts out an announcement that Lambda CDM is dead, other scientists take a look, and a much quieter announcement correcting their work gets put out.

[–] jalda@sopuli.xyz 24 points 1 year ago

Yes, this is a bit frustrating. Part of the scientific method is to propose new hypothesis, and that's what the original author did, so no issue with that. But then there is a chain of increasingly pop-sci media that hype some of these hypotheses as they were already confirmed and accepted by the mainstream scientific community, which is not the case. For example, the title of the article, "New research puts age of universe", that is pure clickbait, the correct tense is, being very generous, "could put".

And when this happens in a field like cosmology, it's relatively harmless. But the same happens in fields that have a more direct impact in the general public's life, like the usual "a couple of years ago they said eggs were unhealthy, and now they say we should eat 5 per day". And the effect is that people stop trusting the recommendations of the experts.

[–] ashe@lemmy.starless.one 15 points 1 year ago

https://doi.org/10.1093/mnras/stad2032

I wasn't able to read the actual paper since it's behind a paywall, but it's not exclusively a TL model. They say this in the abstract:

Deep space observations of the James Webb Space Telescope (JWST) have revealed that the structure and masses of very early Universe galaxies at high redshifts (⁠z∼15), existing at ∼0.3 Gyr after the BigBang, may be as evolved as the galaxies in existence for ∼10 Gyr. The JWST findings are thus in strong tension with the ΛCDM cosmological model.

While tired light (TL) models have been shown to comply with the JWST angular galaxy size data, they cannot satisfactorily explain isotropy of the cosmic microwave background (CMB) observations or fit the supernovae distance modulus vs. redshift data well.

We present a model with covarying coupling constants (CCC), starting from the modified FLRW metric and resulting Einstein and Friedmann equations, and a CCC + TL hybrid model. They fit the Pantheon + data admirably, and the CCC + TL model is compliant with the JWST observations. [..] One could infer the CCC model as an extension of the ΛCDM model with a dynamic cosmological constant.

[–] SakaiSama@sh.itjust.works 6 points 1 year ago (2 children)

The idea of evolving fundamental constants is pretty mind blowing to me. Is this a well based theory?

[–] 1bluepixel@lemmy.ml 19 points 1 year ago* (last edited 1 year ago) (1 children)

I mean, it's a bold idea, but I don't find it so shocking.

It's well possible that what we call a "fundamental" constant is a variable that depends on other deeper variables. For instance, an earth-bound observer might consider acceleration in freefall to be a constant, but knowledge of universal gravitation tells us it's a variable that depends on the masses of the objects involved and distance between them.

It makes sense that other ostensible "fundamental constants" are also dependent on the structure of the universe at any given point in space and time, but the limited window of our observations makes them appear as constants.

[–] SakaiSama@sh.itjust.works 2 points 1 year ago

Sure, but I wouldn’t call gravitational acceleration on earth a fundamental constant, since it’s only locally useful. If something like the charge on an electron started changing though, then there would be profound consequences on the way the universe works

[–] ProcurementCat@feddit.de 2 points 1 year ago

Well, yeah. We know for example that the coupling constant of the strong, weak and electromagnetic interactions are "running", i.e. they change depending on what energies the interacting particles have.

https://www.physicsmasterclasses.org/exercises/keyhole/en/projects/running_alphas.html

That's why we assume that those interactions are all part of one single, more fundamental interaction at very high energies. We already know that the electromagnetic and weak interaction combine into a single interaction at high energies, and it looks like the strong interaction will combine with that at even higher ones.

This doesn't say anything about how those couplings change with (cosmological) time, however.