Application of the NQuantum Approach to a Renormalizable Field Theory
Abstract
The NQuantum Approximation (NQA) is applied to a simple renormalizable field theory, lambda phi^4. Inclusion of the oneloop renormalization of this theory into the NQA approach is demonstrated. Use is made of this oneloop renormalization in a discussion of scattering and the twobody bound state mass. In particular, the function which in the NQA approach plays the role of 2to2 scattering amplitude is derived nonperturbatively in a large N limit. The mass of the twobody bound state is also derived two ways in this limit; from an eigenvalue condition for the twobody bound state wave function and also from the timelike zeroes of the 2to2 scattering amplitude. Our results, using the NQA, agree with previous calculations using other nonperturbative methods. A discussion of spontaneous symmetry breaking (SSB) from the NQA point of view is also given. Equations governing SSB in lambdaphi^4 are derived in a manner easily generalizable to other theories. These equations are used to derive the famous result on oneloop radiatively induced SSB due to Coleman and Weinberg. Our calculation is conceptually simple and leads naturally to the evaluation of only a single diagram.
 Publication:

Ph.D. Thesis
 Pub Date:
 1991
 Bibcode:
 1991PhDT.......154W
 Keywords:

 SYMMETRY BREAKING;
 Physics: Elementary Particles and High Energy