Nonrenormalization of the Wess-Zumino-Witten term in the two-dimensional nonlinear σ model

Pak, Namik Kemal
A coordinate-independent background-field expansion method, suitable for the nonlinear σ models with a Wess-Zumino-Witten term expressed as a three-dimensional integral which makes its topological nature manifest, is developed and applied to both purely bosonic and supersymmetric σ models. This algorithm allows us to compute the quantum corrections over the background-field contribution exactly. It is shown that in the conformal-invariant case, that is when the relation λ2=±4π/k holds between the coupling constants, the Wess-Zumino-Witten term is not renormalized to any order in perturbation theory.
Physical Review D


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Citation Formats
N. K. Pak, “Nonrenormalization of the Wess-Zumino-Witten term in the two-dimensional nonlinear σ model,” Physical Review D, pp. 2396–2401, 1989, Accessed: 00, 2020. [Online]. Available: