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Differential Renormalization of Scalar Field Theory in the Background-Field Method

Yaw-Hwang Chen·Min-Tsung He·Su-Long Nyeo
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Abstract

We introduce an approach for calculating the quantum loop corrections in the $ϕ^4$ theory. Differential regularization and background-field method are essential tools and are used to calculate the effective action of the theory to two-loop order. Our approach is considerably simpler than other known methods and can be readily extended to higher-loop calculations and to other models.

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Yaw-Hwang Chen, Min-Tsung He, Su-Long Nyeo. 1995-09-28. Differential Renormalization of Scalar Field Theory in the Background-Field Method. https://arxiv.org/abs/hep-th/9509164

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