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arXiv · 1305.3373

Form factor approach to diagonal finite volume matrix elements in Integrable QFT

B. Pozsgay
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Abstract

We derive an exact formula for finite volume excited state mean values of local operators in 1+1 dimensional Integrable QFT with diagonal scattering. Our result is a non-trivial generalization of the LeClair-Mussardo series, which is a form factor expansion for finite size ground state mean values.

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B. Pozsgay. 2013-05-15. Form factor approach to diagonal finite volume matrix elements in Integrable QFT. https://doi.org/10.1007/jhep07(2013)157

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