What evidence is their that physical constants have always remained

>>8678144
Considering you think the universe is a trillion years old you're probably high right now but the evidence is simply that there's no reason to think they would be changing.

Even in the oldest galaxies we can see, everything is consistent with assuming the same constants we have now.

>>8678235
We gauge the age of galaxies based on the assumptions the physical constants are the same though.

For example, we spot their distance by their redshift. But if electromagnetic interaction was weaker in the past, the hydrogen energy levels would be squeezed, and the light would naturally be more redshifted than current. In that case, galaxies are actually closer than what we are calculating.

>>8678144
>none
>we dont.

our physical models dont have changing constants and they predicted the CMBR so there's that I guess.

still not a guarantee in the slightest.

>>8678144
I think it unlikely that all the teeny photons go the same exact speed (this is inconsistent with the observable world). And while I'm not familiar with a whole lot of constants, most of them seem irrational (insane). They're good for approximations, I agree, but they're never accurate.

>>8678144
If physical constants can change, how would we be able to tell?

>>8678144
If light were "faster" then time would be faster too and nothing would change

it would still be a constant, it would just be a different constant now

>>8678319
Isn't that the antithesis of a constant?

Quantam super-positioned probabilistic constants?

>>8678251
Objects in mirror are closer than they appear

>>8678235
>Even in the oldest galaxies we can see, everything is consistent with assuming the same constants we have now.
Every single galaxy we see is inconsistent with Newtonian and Einsteinian gravity. Why is the notion of dark matter any more credible than a fundamental constant changing with space/time? Neither have any direct evidence.