I have been thinking about different forms of energy and ways to define them, but I realized that most elementary forms of energy are waves, such as light (a wave in the electromagnetic field). Waves are a transfer of energy, so does that mean light is a transfer of energy? Or is light itself energy?
Waves are a transfer of energy, so does that mean light is a transfer of energy? Or is light itself energy?
Light can be said to have a certain amount of energy. For example, when describing light as a collection of particles (photons) the individual photon's energy is equal to $hf$, where $f$ is the frequency of the light and $h$ is Planck's constant.
It is incorrect to say that light is energy. Rather, it is correct to say light "has" or "carries" energy.
Similarly, light can also be said to "have" a certain amount of momentum. It would be similarly incorrect to say that light is momemtum