Is the mass of the electron constant?

[GeorgeBailey]

There's no good answer to that question, because we do not live in a universe in which "the Compton wavelengths of all atomic particles [are always in] a fixed ratio to the Hubble radius". Thus the question is tantamount to asking what we learn by applying the laws of physics in a situation in which they do not apply - and the answer is that they tell us nothing because they don't apply.

This answer surprises me. The great strength of mainstream physics is that it can always explain what phenomenological nonsense - or at least what contradictions to empirical findings - would happen if one were to replace the established model with a crank idea at any point. You did that pretty well above - a universe in which only the electron changes its Compton wavelength over time, but not the other particles, would look completely different from ours because of the change in mp/me over time.

 

[ohwilleke]

Here's an example of such a study from ten years ago. There have been similar updates of this approach every year or two since then.

 

[GeorgeBailey]

Here's an example of such a study from ten years ago. There have been similar updates of this approach every year or two since then.

Another nice article that shows or rather admits that the sole variation of the electron mass can be empirically refuted, but not a coordinated variation of the masses of all subatomic particles ("Of course, it is possible that several of these quantities are varying, and just by chance all the variation cancels out of the electron mass to proton mass ratio ... So there's a caveat, but it is a small one." ).

Ultimately, everyone can decide for themselves how big or small this caveat is. Just as everyone can answer the question for themselves whether they are convinced that darth... uh dark matter and dark energy (or at least one of both) will be directly detected during the rest of their lifetime.

In making this decision, I myself would pay more attention to the muon precision experiments from 2010 and 2013 (see proton radius puzzle), in which a proton radius of around 0.8412 fm was determined. Thus the ratio of the reduced Compton wavelength of the electron and the proton radius corresponds almost exactly to a quarter of mp/me. The whole confinement approach has no explanation for this match.
Suppose there were two projects to choose from: a new fancy telescope that could finally detect dark energy, or another precision experiment to confirm the conjecture that the proton radius is in a simple numerical relationship to the Compton wavelength of the electron. I bet you that the latter is more promising.