What is a photon?


What is a photon?

In: Physics

A small vibrating particle of light. I’d explain further but I’m not up to date with quantum physics.

A photon is a packet of energy. They are ripples in the electro-magnetic field, and so are crucial to electro-magnetic interactions (one of 4 ways things can interact). They “carry” electro-magnetic forces (including via electro-magnetic radiation, i.e. light), and generally are responsible for anything involving electro-magnetism.

A photon is a teeny tiny little packet of energy. Specifically, a photon is an excitation of the electro-magnetic field.

We can think of the electro-magnetic field like a pond. When we disturb the surface of a pond by tossing a pebble into it, waves ripple out, carrying the energy of the pebble. Similarly when we disturb the electro-magnetic field photons ripple out, carrying the energy that was applied.

There are a couple of ways we can interact with the EM field. One way is to wave a magnet over an an electrical conductor. The energy from that motion is converted into electricity which interacts with the EM field and produces those waves.

Side note: If we had an electronic current moving back and forth very quickly then we would be creating a bunch of photons (EM waves). If we had a way rectify (read) those waves then we would have a radio! That’s what a radio is. 🙂