What is Massless particles: Definition and 52 Discussions
In particle physics, a massless particle is an elementary particle whose invariant mass is zero. The two known massless particles are both gauge bosons: the photon (carrier of electromagnetism) and the gluon (carrier of the strong force). However, gluons are never observed as free particles, since they are confined within hadrons. Neutrinos were originally thought to be massless. However, because neutrinos change flavor as they travel, at least two of the types of neutrinos must have mass. The discovery of this phenomenon, known as neutrino oscillation, led to Canadian scientist Arthur B. McDonald and Japanese scientist Takaaki Kajita sharing the 2015 Nobel prize in physics.
I'm sure this is a very newbie-level question, but how is it that massless particles and light are affected by gravity? I've been reading about the 'ghost condensate' theory, and the latest article in New Scientist that says these massless 'ghost' particles should have been sucked up by black...
Where does the speed of light (~300000km/sec in vacuum) come from
Is this the rotational speed of an electron. Up to Einstein a photon has no mass once it is in movement.
Is the absence of mass the reason why speed of light cannot be modified ?