What are photons made of?

Answer

Delicious question 🙂 as unanswerable as “what does gravity consist of” or “what does love consist of”. So the simple answer is “no, we don’t know”. But you (and I) won’t settle for that.

The complicated answer might go in one of the following directions:

1) “consists of”. Why the hell does something “must” consist of something else? Can’t we just accept that something is absolute in itself? Like numbers, like the dimensions, like existence.

2) we can answer the question “what are photons” or “what do we mean by photons”. A photon is a quantum of the electro-magnetic (“EM”) interaction. This means: it is the amount of energy that an EM wave gives off or absorbs at once from a charged particle, usually an electron. You can imagine this as follows: an EM wave is an electric+magnetic field that propagates through space. A wave has a wavelength and a frequency of vibration. A fixed observer, for example an electron, experiences the passing EM wave as a rapidly varying electric (or EM) field. Since an electron feels the force of the electric (and magnetic) field, and therefore accelerates [kracht=massa*versnelling; en energie=kracht*afstand], it absorbs energy (or releases it if the acceleration is opposite to its velocity). It turns out that this transfer of energy happens in packets exactly proportional to the wave frequency, called “quanta”. The quantum of an EM wave is called a “photon”.

If you look at it that way, a photon consists of EM energy. Next question: what does EM energy consist of then? The energy of an EM wave, so you could say of the photon, is stored in the vector product of electric and magnetic field, the so-called Poynting vector. Next question: what does the electric and magnetic field consist of? Well… from virtual photons some say…