A Photons mass = 0
but
the real Photon's Mass is <1×10âˆ'18eV
a photon's electric charge = 0
but the real electric charge of a photon is <1×10âˆ'35e
http://en.wikipedia.org/wiki/Photon
years ago, science considered the math equation was to tiny of an answer so it was considered to be 0 for charge and 0 for mass and isn't used in any equations but only as 0. even a minuscule equation should not be ignored when developing Quantum theories.