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arXiv · hep-th/9907147

Replica-deformation of the SU(2)-invariant Thirring model via solutions of the qKZ equation

Mathias Pillin
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Abstract

The response of an integrable QFT under variation of the Unruh temperature has recently been shown to be computable from an S-matrix preserving (`replica') deformation of the form factor approach. We show that replica-deformed form factors of the SU(2)-invariant Thirring model can be found among the solutions of the rational $sl_2$-type quantum Knizhnik-Zamolodchikov equation at generic level. We show that modulo conserved charge solutions the deformed form factors are in one-to-one correspondence to the ones at level zero and use this to conjecture the deformed form factors of the Noether current in our model.

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Mathias Pillin. 1999-07-17. Replica-deformation of the SU(2)-invariant Thirring model via solutions of the qKZ equation. https://doi.org/10.1016/s0550-3213(00)00256-x

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