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arXiv · hep-th/9607141

Two-loop scalar diagrams from string theory

Paolo Di Vecchia·Alberto Lerda·Lorenzo Magnea·Raffaele Marotta·Rodolfo Russo
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Abstract

We show how to obtain correctly normalized expressions for the Feynman diagrams of $Φ^3$ theory with an internal $U(N)$ symmetry group, starting from tachyon amplitudes of the open bosonic string, and suitably performing the zero--slope limit by giving an arbitrary mass $m$ to the tachyon. In particular we present explicit results for the two--loop amplitudes of $Φ^3$ theory, in preparation for the more interesting case of the multiloop amplitudes of non--abelian gauge theories.

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Paolo Di Vecchia, Alberto Lerda, Lorenzo Magnea, Raffaele Marotta, Rodolfo Russo. 1996-07-17. Two-loop scalar diagrams from string theory. https://doi.org/10.1016/0370-2693(96)01137-9

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