[jboy55]

>Quantum gravity is obviously the elephant in the room,

Isn't that just our understanding of gravity not being complete.

> the standard model doesn't account for neutrino masses ,matter/antimatter asymmetry, or why the lepton masses are related, and it gets the magnetic moment of the muon wrong. The existence of physics beyond the standard model is certain.

That seems to be a big leap, is not the existence of flaws in our understanding of gravity also certain?

[nyssos]

> Isn't that just our understanding of gravity not being complete.

No. It's that, but it's not just that: if a QFT in 4-d spacetime has a coupling constant with a negative mass dimension, it has infinitely many free parameters, which means you can only use it below a given energy scale. We live in a 4-d spacetime, and the mass dimension of Newton's constant is -2, so either the true theory is not a QFT, or it's an infinitely complicated QFT we can never actually find.

> That seems to be a big leap, is not the existence of flaws in our understanding of gravity also certain?

Yes, both GR and the standard model are known to be incomplete.

[ben_w]

> It's that, but it's not just that: if a QFT in 4-d spacetime has a coupling constant with a negative mass dimension, it has infinitely many free parameters, which means you can only use it below a given energy scale.

Huh.

Do you know of any videos that go into more depth? (My level is the "PBS Space Time" and Sabine Hossenfelder videos as I don't do this professionally).

[nyssos]

No, this is upper level undergrad/introductory graduate material. Popsci is going to be worse than useless.

[ben_w]

Fair enough. I'm definitely not at that level yet, and there's a good chance I'll never find time to reach it.