The more I think about it, the more I realize that I do not understand charge. Especially electric charge and electric fields. Do not even get me started on color charge since my understanding of quarks and quantum chromodynamics would be an embarrassment to any self respecting particle physicist.
I mean, sure. I get the idea that there is a “positive” charge and a “negative” one. I get that different charges attract each other and like ones repel. I get that the charge of the electron is the basic unit of charge and that the proton has the same absolute value as the electron but positive instead of negative and with about 1800 times the mass. I get that a particle with the same mass and opposite charge as an electron is called a positron and that the proton’s analog is called the anti-proton or p-bar. I get that a changing electric charge causes a magnetic field and that a changing magnetic field causes an electric field. All of those things make sense.
What I do not get is … what exactly is a charge?
I mean, a lot of physics is based on the idea that there is no such thing as “action at a distance.” That means that me flapping my arms in Chicago cannot cause a sunspot on Alpha Centauri Proxima unless something carries the information of my action to that destination and initiates the reaction.
So what exactly is interacting between charged particles? What is causing the field? What makes the positive and negative accelerate towards one another? How do they “know” that the other particle is there?
I have heard that Dr. Richard Feynman had a theory involving virtual particle exchange, but I have not read it. I might have to though, if I want to figure things out.
On another note, I have heard that some physicists feel the same way about mass …