Renormalization of the Nonlinear O(3) Model with Theta-Term
arXiv:1208.5948 · doi:10.1016/j.nuclphysb.2013.01.021
Abstract
The renormalization of the topological term in the two-dimensional nonlinear O(3) model is studied by means of the Functional Renormalization Group. By considering the topological charge as a limit of a more general operator, it is shown that a finite multiplicative renormalization occurs in the extreme infrared. In order to compute the effects of the zero modes, a specific representation of the Clifford algebra is developed which allows to reformulate the bosonic problem in terms of Dirac operators and to employ the index theorem.
15 pages, enlarged discussion and minor additional comments, matches published version