Dynamical symmetry breaking in the gauged Nambu-Jona-Lasinio model
Abstract
Description
The mechanism of dynamical chiral symmetry breaking is studied in the Abelian version of the gauged Nambu-Jona-Lasinio model in four dimensions. The most interesting feature of the gauged Nambu-Jona-Lasinio model is the appearance of relevant (renormalizable) four-fermion interactions near a critical curve separating a chiral symmetric and a dynamically chiral symmetry broken phase. The first three chapters of the thesis are introductory. Chapter 4 is based on hep-th/9712123. In an attempt to go beyond standard mean field approximations for four-fermion interactions, the 1/N expansion is utilized in chapter 5. Within the 1/N expansion, where N is the number of fermion flavors, it is shown that the renormalization group beta function of the U(1) gauge coupling has ultra-violet stable fixed points for sufficiently large N. This implies that the gauged Nambu-Jona-Lasinio model is a rare example of a nontrivial nonasymptotically free gauge field theory in four dimensions.
Ph.D. Thesis, University of Groningen, 199 pages, figures included, LaTeX (BibTeX)
Ph.D. Thesis, University of Groningen, 199 pages, figures included, LaTeX (BibTeX)