Tagged Questions
6
votes
3answers
335 views
What makes a Feynman diagram real or virtual?
Simple question: as the title says, what makes a real Feynman diagram real, and what makes a virtual diagram virtual? Or in other words, how do I tell whether any given diagram is real or virtual? ...
5
votes
2answers
411 views
How do we distinguish between virtual particle exchange and particle decay?
The difference between virtual particles and unstable particles is discussed at length in this question (namely, virtual particles correspond to internal lines in Feynman diagrams and are not ...
1
vote
1answer
179 views
Does path integral and loop integral in a Feynman diagram violate special relativity?
Consider a correlation function between two points A(x1,t1) and B(x2,t2), we need to integrate over paths which could be ...
