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arXiv · hep-th/9305119

Marginal Extended Perturbations in Two Dimensions and Gap-Exponent Relations

L. Turban·B. Berche
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Abstract

The most general form of a marginal extended perturbation in a two-dimensional system is deduced from scaling considerations. It includes as particular cases extended perturbations decaying either from a surface, a line or a point for which exact results have been previously obtained. The first-order corrections to the local exponents, which are functions of the amplitude of the defect, are deduced from a perturbation expansion of the two-point correlation functions. Assuming covariance under conformal transformation, the perturbed system is mapped onto a cylinder. Working in the Hamiltonian limit, the first-order corrections to the lowest gaps are calculated for the Ising model. The results confirm the validity of the gap-exponent relations for the perturbed system.

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L. Turban, B. Berche. 1997-09-11. Marginal Extended Perturbations in Two Dimensions and Gap-Exponent Relations. https://doi.org/10.1088/0305-4470%2F26%2F13%2F017

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