- #1
Sleuth
- 47
- 4
Hi guys,
it's been a long time since I wrote here the last time...
I come with a very stupid question... it's only a definition, and it's a matter of ignorance I know that... but nobody ever explained it to me, nor i ever found a clear definition on a QFT book... or probably I simply don't know where to look for it...
the question is, what do people mean with real and virtual corrections? When you compute a process in perturbative QFT i know that real particles are those which are on-shell, or those written as external lines, while virtual particles are the internal off-shell particles in a feynman diagram... but this only confuses me more... why when people talk about computing some process at some perturbative order, they always talk about virtual and real corrections? what's the difference? and what do they mean from a mathematica and mostly physical point of view?
thank you and sorry if this is too trivial,
Sleuth
it's been a long time since I wrote here the last time...
I come with a very stupid question... it's only a definition, and it's a matter of ignorance I know that... but nobody ever explained it to me, nor i ever found a clear definition on a QFT book... or probably I simply don't know where to look for it...
the question is, what do people mean with real and virtual corrections? When you compute a process in perturbative QFT i know that real particles are those which are on-shell, or those written as external lines, while virtual particles are the internal off-shell particles in a feynman diagram... but this only confuses me more... why when people talk about computing some process at some perturbative order, they always talk about virtual and real corrections? what's the difference? and what do they mean from a mathematica and mostly physical point of view?
thank you and sorry if this is too trivial,
Sleuth