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arXiv · hep-th/9802127

Exact Combinatorics of Bern-Kosower-type Amplitudes for Two-Loop $Φ^3$ Theory

Haru-Tada Sato·Michael G. Schmidt
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Abstract

Counting the contribution rate of a world-line formula to Feynman diagrams in $ϕ^3$ theory, we explain the idea how to determine precise combinatorics of Bern-Kosower-like amplitudes derived from a bosonic string theory for $N$-point two-loop Feynman amplitudes. In this connection we also present a method to derive simple and compact world-line forms for the effective action.

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Haru-Tada Sato, Michael G. Schmidt. 1998-02-19. Exact Combinatorics of Bern-Kosower-type Amplitudes for Two-Loop $Φ^3$ Theory. https://doi.org/10.1016/s0550-3213(98)00329-0

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