Verified answer

1) refraction happens when the speed of light changes as a result of a change in the medium through which it is moving. so a material transition is necessary for refraction to occur.

2) gravity bends the light in the sense that the light is moving in a straight line, but the space-time through which it is moving is curved as a result of the presence of a body (or bodies) massive enough to cause the curvature in space-time. no material transition is necessary, but curvature of space-time is required.

3) reflection is a different matter entirely. as in the rutherford experiment, particles which encounter the electromagnetic field of the nuclei in the foil at which they are being shot are reflected backwards toward the source. so a certain type and density of electromagnetic field at the atomic lattice level is required for reflection to occur.

quite the photons that make up easy are basically a million/2 of the question. the different a million/2 of the question concerns the "different" photon which bills for mass. Re: the nicely widely used, disappearing photon try. that is this photon that can no longer get away the grav. field of a black hollow. most of the photons that account for easy can and do get away,. no rely if interior the fashion of sunshine or capacity, i do no longer know yet my guess after thinking S. Hawkins theory, is easy.

um I think maybe it like, when you chase a mouse it runs away really fast, but if you put out some cheese you can make it come to the cheese, so its like you are the mirror and the cheese is the gravity? I'm hungry now D: why did you make me think about mice! oh well I know you didn't mean to make me hungry so its okay! :3