# Talk:Quantum field theory

Rewrite. Sorry no references yet. Will add later. -- Cuddlytakun 14:32, 22 May 2009 (EDT)

I have added a lot of citations, which are accurate but I'm sorry to say, duplicative. I will fix this later, reduce the redundancy. Bear with me.

P.S. I deleted the previous Quantum field theory page because it was mostly inaccurate. The line that said Quantum Mechanics is incompatible with Relativity was not true; Schrodinger's Equation is of course non-relativistic, but the Dirac and Klein-Gordon equations are fully (Special) Relativistic. See "Relativistic Quantum Mechanics" by Bjorken and Drell, McGraw-Hill Inc. I think the title of the book says it all, but see Chapter 1.

The first sentence, that Field Theory is a generalization of QM to infinite degrees of freedom, is true, but vague to the ordinary reader. In my edit, I changed that to emphasize what infinite degrees of freedom we're talking about: namely, unlimited numbers of particles with any arbitrary energies/momenta, and the possibility of CHANGING the number of particles.

The previous line that said field theory is "sometimes called quantum electrodynamics" was just wrong. QED is a SUBSET of field theory. Other parts of field theory include QCD, electroweak theory, and on and on. So saying that field theory is sometimes called QED, is like saying algebra is sometimes called the quadratic equation.

Is there somewhere where I can learn wiki format for citing a previous citation? E.g. the equivalent of Ibid. I want to reduce the duplicativeness of my citations. -- Cuddlytakun 13:10, 2 June 2009 (EDT)

## The Bjorken and Drell book.

I have removed the reference to the 1980 book *Quantum Field Theory*. I can find no such book on Amazon or in other searches, including Google. These two authors both wrote extensively on the subject, and appear to be some of its foremost experts, but I can't find the referenced book, so I have taken the reference out. The closest I can come is a book in the same year, same publisher, and same title, but by Clause Itzykson and Jean-Bernard Zuber. But its chapter 2 is about the Dirac equation.

If someone figures out what book was intended, by all means put the reference back in.

SamHB (talk) 01:17, 1 November 2015 (EDT)

Hmmmm. There is still a reference to this "book", at the end of the second paragraph. I don't know what to do about this. QFT is not really my area of expertise.