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arXiv · hep-th/9604152

Multiloop World-Line Green Functions from String Theory

Kaj Roland·Haru-Tada Sato
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Abstract

We show how the multiloop bosonic Green function of closed string theory reduces to the world-line Green function as defined by Schmidt and Schubert in the limit where the string world-sheet degenerates into a $Φ^3$ particle diagram. To obtain this correspondence we have to make an appropriate choice of the local coordinates defined on the degenerate string world sheet. We also present a set of simple rules that specify, in the explicit setting of the Schottky parametrization, which is the corner of moduli space corresponding to a given multiloop $Φ^3$ diagram.

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Kaj Roland, Haru-Tada Sato. 1997-07-07. Multiloop World-Line Green Functions from String Theory. https://doi.org/10.1016/s0550-3213(96)00447-6

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