Timeline for If all fundamental constants changed proportionally would we know?
Current License: CC BY-SA 4.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 30, 2021 at 17:49 | comment | added | Dale | @AlBrown yes, any combination of units in any system of units could be scaled arbitrarily with no change to the dimensionless constants. | |
| Jul 30, 2021 at 17:36 | comment | added | Al Brown | We could scale mass, distance, charge, and time equally without effect. For classical and relativity, probably not quantum. Can you think of anything that doesnt have those units (eg force does, energy does, even magnetic fields ultimately grounds in moving current)? Or equivalently every constant scales by the factor defined by its units in those terms. But thats a tautology and way different than scaling every constant proportionally, i think. Ok I guess we’ve killed this question esp given its lack of application, even the most theoretical one. Unless of course you have more. Thank you | |
| Jul 30, 2021 at 17:35 | comment | added | Dale | @JohnHunter neither changing your units of time nor your units of distance will change any observations. Having time varying units will also not change any observations but it will make all formulas more complicated. | |
| Jul 30, 2021 at 17:14 | comment | added | Dale | @AlBrown the core concept is right, but it is not a list of constants so much as combinations of constants. The definition/criteria is very clear. Any combination of constants that leave the dimensionless constants unchanged could be scaled without effect. | |
| Jul 30, 2021 at 16:21 | comment | added | Al Brown | My intuition is still telling me there exists some list of “fundamental constants” defining reality that could be scaled without effect. I always thought there was a clear definition of the them? Like constants for “strong nuclear force, weak one, electrostatic force, speed of light in vacuum, charge of an electron, mass of a proton (or maybe a quark?)” stuff like that. I dont know much about it, but does that answer? Looking at that I would guess probably not talking about alpha. This question is more complicated than is obvious. What about item 1 tho? | |
| Jul 30, 2021 at 16:11 | comment | added | John Hunter | If it were proportional to time like $h = h_0 e^{2kt}$, (the 2 is for the length dimension of h), then no change would be noticed locally, but distant stars would have atoms that are smaller than atoms here, so it's tricky to decide whether it could be happening like that... | |
| Jul 30, 2021 at 16:05 | comment | added | Dale | Sure, that would just be changing the SI definition of a meter. You could do the same with any units. That is precisely why such changes don’t change the physics | |
| Jul 30, 2021 at 16:03 | comment | added | John Hunter | If all the terms were to go up by a factor $2^n$ where $n$ is the number of length dimensions in each quantity, then $\alpha$ would be unchanged. | |
| Jul 30, 2021 at 15:30 | history | answered | Dale | CC BY-SA 4.0 |