Tuesday, July 29, 2008

Electric Fields Are Real

O.K. Let's say we have a charged particle or charged object at some location. At some distance away, in principle, we can place a small test charge, release it, and observe it's acceleration. From that we can know the magnitude and direction of the electric field strength. From my point of view there are two options here. On the one hand we might say that by pure magic, i.e., with nothing physically present at the location of the test charge, the charged particle or charged object attracts or repulses the test charge. On the other hand we might say that 'something' that we call an electric field is physically present at the location of the test charge, in fact, is physically present everywhere in space. It's still magic, but only because we don't know exactly what it is or exactly how it does what it does. Personally I prefer the second option. In other words, the electric field of a charge particle or charged object is something real, physically present.

Following that line it seems to me that the physical presence of that electric field is completely independent of whether there are other charges with their electric fields in the vicinity. In other words electric fields of charges 'overlay' each other at any location. One can determine the net electric field at that location, but whatever the net electric field turns out to be, it in no way obviates the physical presence of the underlying primary electric fields.

Continuing that line, since each charged particle has an electric field of infinite extent, it follows that right here in this room where I'm sitting writing the primary electric fields of every single charged particle in the universe is physically present. Can anyone make an argument that this is not the case? You may say, o.k., but so what? Who cares? I'll come back to that.

No comments: