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arXiv · hep-lat/9906012

Four-loop free energy for the 2D O(n) nonlinear sigma-model with 0-loop and 1-loop Symanzik improved actions

B. Alles·M. Pepe
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Abstract

We calculate up to four loops the free energy of the two-dimensional (2D) O(n) nonlinear sigma-model regularized on the lattice with the 0-loop and 1-loop Symanzik improved actions. An effective coupling constant based on this calculation is defined.

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B. Alles, M. Pepe. 2000-01-25. Four-loop free energy for the 2D O(n) nonlinear sigma-model with 0-loop and 1-loop Symanzik improved actions. https://doi.org/10.1016/s0550-3213(99)00604-5

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