system
Given the following post, respond as if you're commenting on Reddit:
human
[Physics] Do fields actually exist?

Take the electromagnetic field, for instance. Photons are quantized, meaning that it takes a threshold energy level for the photon to even exist. On the other hand, photons are excitations of the electromagnetic field. 

Putting these two ideas crudely together: if there's no photon, then that means *there's no excitation in the field*. So if that is true, then how could you distinguish the field from nothingness?

To put it differently, do fields exist independently from their particles?
gpt
> To put it differently, do fields exist independently from their particles?

Yes, fields are much more fundamental. There are QFTs where there are no "particle-like" excitations, so even though there are excited field configurations there is nothing resembling a "particle" in these theories. 

Also, there can exist field configurations which do not have particles in them even for electromagnetism. A static electric or magnetic field - like say a Coulomb field - does not have any photons in it, but it's a nontrivial configuration of the field.

In other words, particles are just particular kinds of excitations in fields, but they're not the only possible excitation.