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arXiv · 1809.04325

On the status of expansion by regions

Tatiana Yu. Semenova·Alexander V. Smirnov·Vladimir A. Smirnov
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Abstract

We discuss the status of expansion by regions, i.e. a well-known strategy to obtain an expansion of a given multiloop Feynman integral in a given limit where some kinematic invariants and/or masses have certain scaling measured in powers of a given small parameter. Using the Lee-Pomeransky parametric representation, we formulate the corresponding prescriptions in a simple geometrical language and make a conjecture that they hold even in a much more general case. We prove this conjecture in some partial cases and illustrate them in a simple example.

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Tatiana Yu. Semenova, Alexander V. Smirnov, Vladimir A. Smirnov. 2019-05-04. On the status of expansion by regions. https://doi.org/10.1140/epjc%2Fs10052-019-6653-3

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