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Two-loop Euler-Heisenberg effective actions from charged open strings

Lorenzo Magnea·Rodolfo Russo·Stefano Sciuto
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Abstract

We present the multiloop partition function of open bosonic string theory in the presence of a constant gauge field strength, and discuss its low-energy limit. The result is written in terms of twisted determinants and differentials on higher-genus Riemann surfaces, for which we provide an explicit representation in the Schottky parametrization. In the field theory limit, we recover from the string formula the two-loop Euler-Heisenberg effective action for adjoint scalars minimally coupled to the background gauge field.

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Lorenzo Magnea, Rodolfo Russo, Stefano Sciuto. 2006-04-13. Two-loop Euler-Heisenberg effective actions from charged open strings. https://doi.org/10.1142/s0217751x06025110

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