Currently I am working through a script concerning QFT. To introduce the concept of canonical filed quantisation one starts with the (complex valued) Klein-Gordon field. I think the conept of quantising fields is clear to me but I am not sure if one can claim that the equations of motion for the field operators have to fulfil same equation as the KG field does.(adsbygoogle = window.adsbygoogle || []).push({});

Mostly this is done in textbooks by pure calculating (see Peskin/Schroeder sec. 2.4). Is this somewhat of luck or this is not everytime the case that fieldoperators do not fulfil the equations of motions of their corresponding (classical) fields?

Or is it always allowed to demand the same equations of motions as the fields would fulfil?

(look here

http://theorie.physik.uni-giessen.de/~hees/publ/lect.pdf

formula 3.72)

maybe someone understood what I was trying to say and has some help for me. thx

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Field Operators in Klein-Gordon theory

**Physics Forums | Science Articles, Homework Help, Discussion**