Hello All, I have read that because the Neutrino has so little mass, and because it is not affected by the Electromagnetic Force that it can travel through light years of solid lead. The photon is also mass-less, I believe. Why can it not do the same as neutrinos? I understand the photon is the force carrier for the electromagnetic force. Does that mean the photon is so affected by the force that it represents that it cannot travel through lead as a neutrino can?