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Scaling Lee-Yang Model on a Sphere. I. Partition Function

Al. Zamolodchikov
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Abstract

Some general properties of perturbed (rational) CFT in the background metric of symmetric 2D sphere of radius $R$ are discussed, including conformal perturbation theory for the partition function and the large $R$ asymptotic. The truncated conformal space scheme is adopted to treat numerically perturbed rational CFT's in the spherical background. Numerical results obtained for the scaling Lee-Yang model lead to the conclusion that the partition function is an entire function of the coupling constant. Exploiting this analytic structure we are able to describe rather precisely the ``experimental'' truncated space data, including even the large $R$ behavior, starting only with the CFT information and few first terms of conformal perturbation theory.

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Al. Zamolodchikov. 2001-09-09. Scaling Lee-Yang Model on a Sphere. I. Partition Function. https://doi.org/10.1088/1126-6708%2F2002%2F07%2F029

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