However, if we consider a photon is a particle, then, collision will be a proper word for radiation. My idea is that if one of the collision parties is a photon, then, the collision is named radiation. If both parties in a collision are photons then the collision is related to the transportation of heat but the possibility of that kind of collisions is so tiny that people can ignore it for the time being. When the technology is ready to detect that kind of collision then people can name it and study it. If at least one of two parties in a collision contains atoms then it is the 2nd way of transporting heat and people can measure the temperature of the party with atoms. I don't have a good name for it yet, let me call it ?contact? for now. I will explain my definition in more detail.
Light is a pulse or a ray of photons. Light is a wave and photons move along a cycling path. However, if photons have no charge, then people should not say light is electromagnetic wave (EM wave), isn't it? Only if photons have charges, the name of EM wave can make some sense. I will say even if photons have charges, the name of EM wave is still a miss guiding. The main reason is a photon may go to a direction that nothing is before it, but a cycling electronic field makes sense only when there is another photon around that moving photon. Isn't it? Light is the main topic of my paper. I will show you how people misunderstand the light in more detail.
