I don't really understand energy-momentum... Regarding the fundamental fields in the standard model: Could the gluons in an atom (and the atom itself), ever be stationary to spacetime? I'm assuming not because that would seem like the atom didn't have gravity or ...whatever? (I can't really word the question, I mean like if it wasn't moving there wouldn't be a perturbation in the Higgs field or exchange of energy to slow the atom down) My thinking is (and this may be a misunderstanding in my own premise) that if everything is travelling at the speed of light by default, and gravity just constant exchanges of Higgs energy with the Higgs field (I presume through Higgs bosons?) that causes things to experience time and have mass...or is it just gravity? Is the equivilancy between mass and energy (M = E / c^2) due to the Higgs field? Also, are gravitons like the virtual photons of the Higgs field? Please forgive my ignorance and poor wording. Hopefully it's all not as silly as it sounds. Thanks.