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arXiv · hep-th/9605198

Covariant background field calculation of ultraviolet counterterms

F. M. de Carvalho Filho
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Abstract

Based on the covariant background field method, we calculate the ultraviolet counter\-terms up to two-loop order and discuss the renormalizability of the three-dimensional non-linear sigma models with arbitrary Riemannian manifolds as target spaces. We investigate the bosonic model and its supersymmetric extension. We show that at the one-loop level these models are renormalizable and even finite when the manifolds are Ricci-flat. However, at the two-loop order, we find non-renormalizable counterterms in all cases considered, so the renormalizability and finiteness of such models are completely lost in this order.

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F. M. de Carvalho Filho. 1996-05-28. Covariant background field calculation of ultraviolet counterterms. https://arxiv.org/abs/hep-th/9605198

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