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arXiv · 1208.5948

Renormalization of the Nonlinear O(3) Model with Theta-Term

Raphael Flore
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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.

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Raphael Flore. 2013-03-10. Renormalization of the Nonlinear O(3) Model with Theta-Term. https://doi.org/10.1016/j.nuclphysb.2013.01.021

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