[Physics] Are the particle-antiparticle pairs produced in vacuum virtual particles, and can they interact with normal particles

pair-productionquantum-field-theory

If it is true that due to energy fluctuations of a vacuum being able to produce a particle-antiparticle pair that shortly annihilate with each other and disappear again, is the following circumstance possible?here

I was then thinking that if this was the case, there would be some inherent uncertainty to any particle's position, because of the particle/antiparticle production in vacuum was random, then if I leave an electron in a specified place for a short period of time, the pair production could have caused the electron to move. This seemed to fit in really well with the concept of a wave function, and that we can never predict a particle's position with 100% accuracy, and to me this seemed to offer some sort of an explanation as to why this was the case.

The only knowledge I have on this topic is knowledge gained through pop-science, and so I don't really understand much of this at all, so any help understanding would be great. I talked to my friend about this, and he said something along the lines of "the pair production particles aren't 'real' particles, and they can't really interact with anything", though I'm not too sure I understand what that means.

Best Answer

I talked to my friend about this, and he said something along the lines of "the pair production particles aren't 'real' particles, and they can't really interact with anything", though I'm not too sure I understand what that means.

Your friend is correct.

A virtual particle is a mathematical construct, it is a creation of the mathematical model used to fit elementary particle physics. This model has an iconal representation for the mathematical formulas that build up the functions that give the probability of interaction for elementary particles. . These are the Feynman diagrams and all the lines correspond to functions and the vertices to the strength of the interactions described by the iconal representation.

fdiagram

The particles in the table are real , their properties have been measured in the lab, and the theoretical model fitting them is the standard model. They are represented in the above diagram with the arrows. The exchanged wiggly line is a virtual photon, not a real one. A virtual particle has a varying mass, not the mass on the table, because it represents an integral over the variables. The reason it keeps the name, in this case photon, it is because it carries the all the relevant quantum numbers of the name.

A virtual particle can never be measured by construction of the integrals.

Thus in pair production from the vacuum the pair cannot become real , your middle diagram, unless there exists an interaction where energy is supplied, and one of the particles can become real as with the Hawking radiation effect, where the gravitational potential of the black hole supplies the energy.

Related Question