Yes, the speed of light through a medium is different for different wavelengths. (Read about refraction.) The simplest explanation is the electric-magnetic waves interact with the charged particles in the medium. If you read about Maxwell’s equations, you’ll see that the speed of propagation through a medium depends on its permittivity and permeability (constants describing the “stretchiness” of the medium to electric and magnetic fields, respectively).
That’s all based on a wave description of light. If you want to use a particle-based description, you can assign an effective “mass” to photons in a medium, which causes them to move slower than c. Just as Higgs bosons cause particles to have mass, virtual photons from the medium give mass to the photons propagating through it.
The reason why we can describe gravity as a distortion of spacetime is that it affects everything equally. If there was something not affected by gravity, gravity-as-spacetime-warping wouldn’t work as a description of reality.
Claudia de Rham, Gregory Gabadadze, and Andrew J. Tolley published “Resummation of Massive Gravity” in Phys. Rev. Lett in 2011.
And that, fellow non-scientists, is why these jargon-free discussions seldom satisfy.
They apparently got massive, pun deliberate, pushback on this. But an article in The Guardian this year says it’s gaining attention because the math works, although there is yet no evidence.
I’m mentioning this solely because it was so recent I remembered the article. You physics people can do all the commenting on it.
The total influence on a how an object/particle/etc behaves will always depend on all the influences, but when the total influence is just the sum total of the influences then the situation can be described linearly, but when those influences are also influencing each other then it is non-linear.
Waves and interference are linear phenomena, but can be used to describe gravity in certain situations when the self-interaction can effectively be ignored.
Since we’re mentioning the weak gauge bosons, it’s worth noting that the Z particle behaves very much like a photon, except that it has mass. But any interaction that a photon can mediate, a Z can also mediate (and in fact, a complete description of either electromagnetism or the weak force is impossible without including the other).
Exapno Mapcase, I haven’t read that article, but from the abstract, it sounds like it’s addressing a toy model: A model which does not correspond to any known real phenomenon in nature, but which is in some way simpler than the real phenomena, and which has some interesting properties to be examined which might be somewhat analogous to real properties. In other words, it’s not saying that the graviton really is massive; it’s saying that thinking about what gravity would be like if it were can lead to interesting results.
Like separate sets of ripples on a pond intersecting?
Not being a scientist, a large part of my misunderstanding of gravity comes from too many dumbed-down science shows that demonstrated gravity with the ‘bowling ball on a trampoline’ method.
So when I think of situations of things (like light) not being affected by gravity I think of the above example with a yardstick laid across the depression as a possible direction of travel.
I know that’s not right (now) but it’s hard to get those early ‘lessons’ out of my head.
Gravitational waves do interfere in (almost) the same way as any other waves. In fact, a large part of the difficulty in detecting them is that your detector is always detecting all the gravitational waves that are passing through it, and you have to break that down into all of the separate waves. Though admittedly this isn’t as big a problem for the LIGO-type detectors (the only ones that have actually made definite detections), because in those frequency ranges, you’ll usually have one source at a time that’s much stronger than the others.
The “almost” there, incidentally, is because gravity is non-linear (that is to say, gravity itself gravitates). But for gravitational waves that might realistically be passing by Earth, the wave amplitude is so small that the nonlinearity can safely be completely neglected (the wave itself only shows up when you look at changes as small as one part in around 10^20, so the nonlinearities would be way down at 1 part in 10^40).
People don’t have much experience with non-linear waves - but this video of oobleck might demonstrate how weird those waves can get Non-Newtonian Fluid on a Speaker Cone - YouTube - for a much smaller driving force, the waves would look like typical water waves, but the driving force of the speaker cone is evidently large enough for the nonlinearity to be obvious.
As I understand it, the electroweak force has 4 bosons, all of which are massless. Two of them are mixed to form the W+ and W- bosons, and the other two are mixed to form the Z and photon. The W and Z have mass because of the Higgs boson, but I don’t really understand why the Higgs affects them and not the photon.