- #1
robousy
- 334
- 1
Hi,
I have a question regarding normal ordering in QFT.
I know that it moves dagger operators to the right and that it gets rid of infinite constants turning up and that 'with observables defined in normal products their vacuum expectations vanish.' (Mandl and Shaw)
I have a couple of questions.
1) Is this an ad-hoc intruduction, I mean, if it changes the answer then how do you justify doing it (even if it does get rid of infinity).
2) If the vacuum expectation vanishes then that means it goes to zero right? Then what is the point if your answer vanishes?
Please help enlighten me here!
Richard
I have a question regarding normal ordering in QFT.
I know that it moves dagger operators to the right and that it gets rid of infinite constants turning up and that 'with observables defined in normal products their vacuum expectations vanish.' (Mandl and Shaw)
I have a couple of questions.
1) Is this an ad-hoc intruduction, I mean, if it changes the answer then how do you justify doing it (even if it does get rid of infinity).
2) If the vacuum expectation vanishes then that means it goes to zero right? Then what is the point if your answer vanishes?
Please help enlighten me here!
Richard