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arXiv · 2208.07636

Schwinger, ltd: Loop-tree duality in the parametric representation

Marko Berghoff
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Abstract

We derive a variant of the loop-tree duality for Feynman integrals in the Schwinger parametric representation. This is achieved by decomposing the integration domain into a disjoint union of cells, one for each spanning tree of the graph under consideration. Each of these cells is the total space of a fiber bundle with contractible fibers over a cube. Loop-tree duality emerges then as the result of first decomposing the integration domain, then integrating along the fibers of each fiber bundle. As a byproduct we obtain a new proof that the moduli space of graphs is homotopy equivalent to its spine. In addition, we outline a potential application to Kontsevich's graph (co-)homology.

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Marko Berghoff. 2022-08-16. Schwinger, ltd: Loop-tree duality in the parametric representation. https://doi.org/10.1007/jhep10(2022)178

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