Vacuum fluctuations and QM

TrickyDicky

How are internal lines with no free ends of Feynman diagrams of the perturbative expansion of QFT related to the quantum tunnelling barrier's negative kinetic energy and the HUP of QM? (if they are related at all)

TrickyDicky

Not a clue anyone?
Maybe quantum tunnelling is considered not mainstream?

tom.stoer

Good question.

I have to look for a paper from Jaffe which explains that vacuum bubble diagrams (w/o external lines) for the Casimir effect are an "effective limit" of standard 1st order diagrams with external lines for van-der-Waals forces. If this reasoning could be used in general than vacuum bubbles might be irrelevant.

TrickyDicky

In fact my question wasn't restricted to vacuum bubbles diagrams, I was referring to virtual particles in general.
Vacuum bubbles are irrelevant (cancel) when calculating correlation functions.

sheaf

You mean this one?

tom.stoer

exactly, thanks!