For example, thermal energy exists and has no mass, but is carried by particles which have mass. A photon is described as a particle - how can a photon exist on its own, travel in space and even push other particles with mass if it has no mass itself?
Asked
Active
Viewed 38 times
1
-
@Kyle Kanos I am not asking about momentum – nbvmnm Sep 26 '14 at 02:08
-
2The relationship to energy is given in the proposed duplicate; the relationship to momentum (which allows it to "push" other particles) is also discussed. – Kyle Kanos Sep 26 '14 at 02:12
-
Photons don't have rest mass. Neither does thermal energy. There are, of course, no resting photons and the thermal energy of resting particles is zero. No contradiction. – CuriousOne Sep 26 '14 at 03:32
-
What we talk about mass in modern physics is rest mass. Photons never have a "rest" , you can't "catch up with " it and "measure" its mass. – Simon Sep 26 '14 at 04:09