Einstein wrong? Speed of light not constant?

Here is an article from Reuters on AOL. If you don’t have AOL there’s no way for me to link this, so I’ll try to put as much critical info from it without pasting the whole thing. Post your thoughts!

Take a look at Bye Bye, Speed of Light over in Great Debates.

The thing that might be changing is something called the Fine Structure Constant. This is defined as the square of the charge of an electron, divided by two times Plank’s constant times the speed of light times the permissivity of the vacuum. They’ve decided that the part of the equation least unlikely to be variable is the speed of light, but that’s still a very controversial claim.

The speed of light measured in meters per second is constant by definition. In October 1983 the meter was defined as the distance light travels in 1/229,792,548 second. This means that the speed of light is necessarily constant and equal to 229,792,548 meters per second. According to Relativity, this definition is equivalent to a definition using (idealized) rigid rods. If the two definitions are not equivalent, then we can ask if rigid rods change length, but the speed of light cannot change.

I would have thought that the units of electric charge would be defined in terms of the electron’s charge, which would make the electron’s charge necessarily constant. I looked up the definition of charge in a physics book. My book said that the unit of electric charge is the Coulomb and it was defined in terms of the second and the ampere. It said that the ampere would be defined in later chapter. I look ahead for the definition of ampere and find that the ampere is defined as one Coulomb per second :rolleyes:

Wrong kind of photon? How many kinds are there?