| MadSci Network: Physics |
This is a very complicated question-- the math and physics that lead to the Higgs boson won a Nobel Prize. First question: the mass of the Higgs boson has no (or really, very little) relationship to the masses of the quarks (that which make protons), leptons (electrons, muons, taus, and neutrinos), and the other bosons (such as the photon, and the W and Z bosons). If it did, then knowing the masses of all of those other particles-- which we do very well-- would have told us the mass of the Higgs boson and we would have found it much much sooner. Instead, the Higgs boson is the physical manifestation of a field that gives all of the other particles mass. Again, this is very complicated; if you want to know, write in again and we'll give it a shot. This also goes for the second question: the Higgs field, which manifests as the Higgs boson, is needed for spontaneous symmetry breaking, which in turn causes the photon to be massless and the W and Z bosons to be massive, and the leptons and quarks to also be massive. The lifetime of the Higgs is moot. As for your third question, remember that inertial is just mass times velocity; we now know the mass, and that's the really interesting bit.
Hope this helps!
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