Hi, I'm a vet with an amateur interest in physics. In discussion with a friend about the usefulness of physics he stated that physicists had not even decided whether light was a wave or a particle. I said the following: 'The question of whether light is a wave or particle is not one which really troubles modern physicists. A photon is not something we can describe in terms of things we humans can see with our eyes. If you do an experminent to see if light is a wave, it is; if you do the same for particles, it is too. Quantum physics tells us that photons are quanta of electromagnetic waves, so if you were to twist my arm I'd say it is a particle which has emergent wavelike properties. Photons are described by wavefunctions and governed by quantum amplitudes; these are complex numbers and as such have a magnitude and also a phase. This phase rotates as time goes on and gives rise to an illusion of wavelike behaviour.' Was I taking crap?