rationalskepticism.org

epepke wrote:

More to the point: E=mc2 is a simplification at rest for a more complicated formula that relates energy and momentum with rest mass.

A photon has energy and momentum. When you use that formula, the rest mass is zero. This can only happen if the photon always moves at c

Yes, the formula is:

E2 = (pc)2 + m2c4

In the case of a photon, m=0 leaves you with E=pc.

twistor59 wrote:

eric8476 wrote:what makes a photon a particle if it is not mass? why isn't it energy? or is that for the next nobel prize?

Good question. I'd say it's debatable whether we should really use the term "particle" in connection with photons !

Ha, ha, Einstein would disagree -- his explanation of the photoelectric effect went against the thinking of the day since light was thought as waves since Maxwell, and a course in QFT would convince you otherwise. Photons are the "particles" that mediate the electromagnetic force. Without that, you might as well through QED under the bus.


I'm still waiting for what would be the ramifications should the Higgs bosons be ruled out. Any thoughts?