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> there are really no convincing arguments for or against LCDM because it's highly sensitive to the galaxy formation model that's adopted. To be fair, that is
by ajross 2y ago
> there are really no convincing arguments for or against LCDM because it's highly sensitive to the galaxy formation model that's adopted.
To be fair, that is absolutely not the way ΛCDM would have been described to someone in the pre-Webb days. It was a well-regarded theory and the hope was (a-la the Higgs detection) that new data would just better constrain the edges and get us on to the next phase of the problem.
But instead it's a wreck, and we didn't see what we were expecting at all, and so now we're retreating to "Well, ΛCDM wasn't exactly proven wrong, was it?!"
That doesn't mean it's wrong either, and it for sure doesn't mean MOND is right. But equally for sure this is a Kuhnian paradigm shift moment and I think it's important for the community to be willing to step back and entertain broader ideas.
- astroH 2y agoAgain, LCDM and galaxy formation are two different things. "...and we didn't see what we were expecting at all..." It depends on who you ask. There were many pre-JWST models that did well in this regard. A particularly interesting one is this from 2018 (https://ui.adsabs.harvard.edu/abs/2018MNRAS.474.2352C/abstract https://ui.adsabs.harvard.edu/abs/2018MNRAS.474.2352C/abstra...). That group even had to write another paper reminding everyone of what they predicted (https://ui.adsabs.harvard.edu/abs/2024arXiv240602672L/abstract https://ui.adsabs.harvard.edu/abs/2024arXiv240602672L/abstra...). Another example is here (https://ui.adsabs.harvard.edu/abs/2023OJAp....6E..47M/abstract https://ui.adsabs.harvard.edu/abs/2023OJAp....6E..47M/abstra...) which shows results from a simulation from ~2014. I can provide numerous other examples of this. My point isn't which theory is or isn't wrong, my point is that what is presented in this particular article is not a constraint on any realistic theory of gravity as the sensitivity of these particular observations to galaxy formation modeling is so strong.
- Davidzheng 2y agoAbsolutely not in the field, so if you are please completely disregard. But from conversations with physicists (not cosmologists) I always thought people thought a lot of evidence for ΛCDM was dubious at best.
- liquidpele 2y agoDubious at best, lol, Isn’t that half of all of cosmology? Lots of pure math these days and little science it seems.