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Ising model with a boundary magnetic field - an example of a boundary flow

Anatoly Konechny
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Abstract

In hep-th/0312197 a nonperturbative proof of the g-theorem of Affleck and Ludwig was put forward. In this paper we illustrate how the proof of hep-th/0312197 works on the example of the 2D Ising model at criticality perturbed by a boundary magnetic field. For this model we present explicit computations of all the quantities entering the proof including various contact terms. A free massless boson with a boundary mass term is considered as a warm-up example.

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Anatoly Konechny. 2004-11-03. Ising model with a boundary magnetic field - an example of a boundary flow. https://doi.org/10.1088/1126-6708%2F2004%2F12%2F058

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