|MadSci Network: Physics|
First, I must confess I have not learned any particle physics at school yet. Therefore my answer will not be very exact.
One of the most important laws of quantum mechanics is the principle of uncertainty. A consequence of this is that there is no absolute void. That is what we classically denote by "void" is actually filled with virtual particles. And why is that? Because in a region of space with zero energy (absolute void) the principle of uncertainty tells us that for a very short period of time we can have a small fluctuation in energy. The relation between this quantities is E * t = ct (1). If the energy is not zero there must be something that has that energy, and we call this a "virtual particle".
Now back to our problem. If we talk about interaction between two electrons thru a virtual particle we mean that a small fluctuation in electron's 1 energy makes a virtual photon appear which travel to electron 2 and is absorbed. The same happens in the other direction. But we know exactly how long this photons are alive because we know the distance and the speed (c = 3E+8 m/s). This means that we can find out their energy, frequency and so on by using relation (1). I leave this to you.
Let me rephrase your second question in terms of electromagnetic fields. "Is it possible to neutralize the current into a wire by applying a proper electromagnetic wave?" The obvious answer is yes, because any wire behaves (more or less) as an antenna.
Feel free to email me if you don't like the answer or have some feedback.
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