- #1

Pushoam

- 962

- 51

particle nature of light. So, what is light?

According to the photoelectric effect, light consists of photons with energy E and momentum ## \vec

p##.

According to the interference pattern, we don't know where an individual particle will reach on the screen.

So, considering one-dimensional case, what I understood is that there is a wave - function ## \psi (x,t) ## associated with each photon such that ## |\psi|^2 dx ## tells us the probability of finding the particle in the region dx at time t. So, if a particle reaches x at time t then it can be said that the particle has momentum ## \vec p ## and energy E at x and t. Thus, it is meaningless to say that the particle has momentum ## \vec p ## and energy E without specifying its position and time.

Thus, what we can say is the probability of finding the particle with momentum ## \vec p ## and

energy E in dx at time t. Thus, the probability of finding the energy of particle to be E in region dx at time t should be given as E ## |\psi|^2 dx ##.

I don't understand why the author is emphasizing that ## \psi ## is associated with each particle, not a collection of particles.