(March 6, 2016 at 10:23 am)Alex K Wrote:(March 6, 2016 at 10:15 am)little_monkey Wrote: No, you didn't understand my post. Seeing means detected by not only your eyes, but also by any detector that will indicated it has been hit by those particles, either by a flash or a jump in voltage. Virtual particles are exchanged between two other particles, so those particles are NOT going to hit your eyes or any other detector. It's that simple.
What's the conceptual difference between particles in a detector (which is made from particles) and "two other particles"?
The difference is not in the concept in terms of what "is" a particle, but that are involved differently. The particles that can be observed are those registering on your eyes ( or any detectors you wish to use). So you can say they interact with you (or an observer/detector). The virtual particles are those involved in the interaction between other particles. Therefore, they are not interact with you (or any other observer/detector). The word "virtual" is to distinguish these two cases, but a photon is a photon whether it interacts with you, hence its a "REAL" particle, or it interacts between two electrons, hence "VIRTUAL".
