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arXiv · hep-th/9906068

World-line Green functions with momentum and source conservations

Haru-Tada Sato
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Abstract

Based on the generating functional method with an external source function, a useful constraint on the source function is proposed for analyzing the one- and two-loop world-line Green functions. The constraint plays the same role as the momentum conservation law of a certain nontrivial form, and transforms ambiguous Green functions into the uniquely defined Green functions. We also argue reparametrizations of the Green functions defined on differently parameterized world-line diagrams.

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Haru-Tada Sato. 1999-06-09. World-line Green functions with momentum and source conservations. https://doi.org/10.1063/1.533049

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