polarization is sort of like a little arrow that each photon carries with it that can point in different directions. But it’s not quite that simple. For one thing, we can’t actually tell what direction a photon’s polarization arrow is pointing. All we can do is measure a photon’s polarization along one particular axis at a time in a somewhat indirect manner, by shooting it at a polarizer (like a lens in a pair of polarized sunglasses). When a photon hits a polarizer, it either passes through or gets blocked; the closer the photon’s polarization is to the polarizer’s axis, the more likely it is
...more
polarization
