Why is it that we can see only light and not any other boson like say, gluon or graviton?
We can't see gravitational radiation because its cross section for interaction with ordinary matter is extremely small. That is, a zillion gravitons could pass straight through your eyeball with none of them being absorbed; so there's no way you could "see" them. (This is related to the fact that gravitation is a very weak force.) Even our largest and most sophisticated detectors [LIGO] have so far failed to detect gravitational radiation; there is no way it could be done by the eyeball.
We can't see W and Z bosons or Higgs bosons for two reasons:
We can't see gluons because they are colour-confined within hadrons, just like quarks. You can't make a beam of free gluons like you can make a beam of light. Any event that produces any gluons must also produce other gluons or quarks, and the result is that the gluons become bound up in hadrons within a tiny fraction of a second.
We can't see W and Z bosons or Higgs bosons for two reasons:
- because they are extremely massive; hence they require large amounts of energy to produce, which did not exist on Earth until the construction of powerful accelerators in the late twentieth century. So there would certainly have been no evolutionary advantage whatsoever to being able to see W, Z, or Higgs bosons.
- because they are so short-lived that most of them won't even be able to traverse the diameter of an atomic nucleus before decaying
We can't see gluons because they are colour-confined within hadrons, just like quarks. You can't make a beam of free gluons like you can make a beam of light. Any event that produces any gluons must also produce other gluons or quarks, and the result is that the gluons become bound up in hadrons within a tiny fraction of a second.