This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Homework Set No. 4, Physics 880.08 Deadline Wednesday, December 8, 2010 at NOON! 1. Timeordered product of real scalar fields is defined by T ( x ) ( y ) = ( x y ) ( x ) ( y ) + ( y x ) ( y ) ( x ) , where s are operators in Heisenberg picture. a. (5 pts) In a free scalar field theory with mass m use KleinGordon equation along with the canonical commutation relations to show that [ 2 + m 2 ] T ( x ) ( y ) = i 4 ( x y ) where the derivative squared (the DAlembertian) is taken with respect to 4coordinates x . b. (10 pts) Similar to what we did in class for retarded Green function, find an explicit expression for the Feynman propagator in coordinate space in a massless ( m = 0) theory by performing the following integral D F ( x y ) = integraldisplay d 4 k (2 ) 4 e i k ( x y ) i k 2 + i . Is Feynman propagator causal?...
View
Full
Document
This note was uploaded on 07/28/2011 for the course PHYSICS 880.08 taught by Professor Staff during the Fall '10 term at Ohio State.
 Fall '10
 Staff
 Work, Quantum Field Theory

Click to edit the document details