Quote originally by Alexander from religion forum. "Don't you know that photons are MATTER? Being bosons they obey different statistics than fermions (electrons, protons), rather than that have same properties other particles have - they are wavy (as all particles), have spin, momentum, energy. What makes you think that photons are not matter? By the way, if you place about 3x1035 of green photons in a massless box, the box will acquire mass 1 kg. (Both inertial mass and gravitational mass)." Is this true? The last that I read from books published as late as 2002, photons were still considered quantum packets of energy with zero rest mass and traveled at the speed of light, not matter which has mass and therefore cannot travel at the speed of light.