Hi, So this question might be a little simple, or not. But I was wondering about the exact nature of magnetic fields. Now obviously magnetic fields work in a vacuum(due to the fact that it's not a perfect vacuum), but would a magnetic field exist in a theoretical perfect vacuum? Now I think this would be a rather difficult experiment to perform, in order to see if the field is there, we would have to insert particles into the space were we suspect the field might be. Is there a mathematical model or theory to prove of disprove this without altering the experiment itself? Or could this be a question along the line of "a tree falling in the woods without anyone around.. blahblah" Am I missing something fundamental? Any thoughts or insight would be peachy, thanks.