Is physics invariant under global regauging of c?

[decraig]

The title should have been:

 

"Is physics invariant under global regauging of c?"

 

 

The geometrical constant relating dimensions of time and distance is c=~300,000 km/sec.

 

Are the laws of physics invariant under regauging of c; that is

 

[math]c \leftarrow c' = b c[/math]

where b is real scalar?

 

I'm sure there's something obvious I'm missing.

Edited January 22, 2014 by decraig

[ajb]

I would think you would pick up factors of b all over the place in your equations and so generally we won't have invariance in the sense that the laws are totally insensitive to this rescaling. You could also try thinking about this in terms of group theory and the representations of the Lorentz group, I guess.

 

They are invariant in the sense that we can make some other choice of units when defining the value of c and the physics won't change, of course being careful with the other constants that we have.

[decraig]

I would think you would pick up factors of b all over the place in your equations and so generally we won't have invariance in the sense that the laws are totally insensitive to this rescaling. You could also try thinking about this in terms of group theory and the representations of the Lorentz group, I guess.

 

They are invariant in the sense that we can make some other choice of units when defining the value of c and the physics won't change, of course being careful with the other constants that we have.

Doh! Yes, replacing c with bc is the obvious part I missed, such that, if b canels on both sides of a set of equations, then those equations are invariant under rescaling of c.

Edited January 23, 2014 by decraig