Real: something which has objective existence. Note that things which are just a description of something that has an objective existence are not, at least for my definition, real themselves.
The only reason I mentioned gods is that they're the easy escape route... my rough definition of a god would be as "the original real thing which is a cause but needs no cause itself." I don't assume that gods exist... I'm an atheist actually, so I assume gods don't exist.
I don't assume we can understand all causes... nor even that it's even theoretically possible to understand all causes, nor that absolutely everything has a cause. The study of physics, however, assumes that everything has a cause... so for the purposes of understanding how physics derives the idea of physical forces I must go along with that assumption.
It's like software engineering. The universe is treated as a function. We're given this huge complex function which seems to be doing lots of different things, and we want to understand the function better. The goal of physics is to reverse-engineer this function which we are all a part of. Physicists examine the logic of how the function works, and they derive from that a set of preconditions which they call "physical forces," or sometimes when they're thinking more clearly "physical laws." Remember, we're all inside the function, so we never actually
see the preconditions and in fact the preconditions don't actually exist for us since they're not inside the function... we only know that what's going on in the function seems consistent with what a certain set of preconditions would produce. No physical force has any reality on its own, it must have something to act on just as a precondition must be run through the function in order for it to do anything. The preconditions (physical forces) are themselves nothing more than logical simplifications science has created in order to understand the function (universe) better.
It seems to me as though there can't be any actual
real preconditions for the universe, because that would mean there's something outside of the universe and the definition of the universe would automatically expand to incorporate it... at which point science would have to develop preconditions for the now-real things that we used to call preconditions, and it'd go on like that forever. So, what's real is only the complex effects of the physical laws (i.e., all the interactions we observe between everything in the universe), not the physical forces we use to describe the effects and sometimes mistakenly think of as the cause. That's why there's no actual reality to the physical forces: they have descriptive value, and the whole point of them is to describe things other than themselves in a consistent manner, but they have no actual reality of their own.
What we call physical forces are simply laws of interaction. They're not really forces, just descriptive laws.
I hope that's clearer.
