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arXiv · hep-th/0112057

Non local Thirring model with backward and umklapp interactions

V. I. Fernández·C. A. Iucci·C. M. Naón
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Abstract

We extend a non local and non covariant version of the Thirring model in order to describe a many-body system with backward and umklapp scattering processes. We express the vacuum to vacuum functional in terms of a non trivial fermionic determinant. Using path-integral methods we find a bosonic representation for this determinant which allows us to obtain an effective action for the collective excitations of the system. By introducing a non local version of the self-consistent harmonic approximation, we get an expression for the gap of the charge-density excitations as functional of arbitrary electron-electron potentials. As an example we also consider the case of a non contact umklapp interaction.

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V. I. Fernández, C. A. Iucci, C. M. Naón. 2001-12-07. Non local Thirring model with backward and umklapp interactions. https://doi.org/10.1016/s0550-3213(02)00399-1

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