It could mean that the dimensionless constant “alpha”, also known as the “fine structure constant”, varies, and the simplest way to express that change mathematically is as a change in C rather than in one of the other parameters (such as the charge of the electron).
What would it even mean for the speed of light to not be constant, other than we’re using the wrong system of coordinates?
It could mean that the dimensionless constant “alpha”, also known as the “fine structure constant”, varies, and the simplest way to express that change mathematically is as a change in C rather than in one of the other parameters (such as the charge of the electron).
(I read a book about this.)