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arXiv · 2205.13762

Locality and Analyticity of the Crossing Symmetric Dispersion Relation

Debapriyo Chowdhury·Parthiv Haldar·Ahmadullah Zahed
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Abstract

This paper discusses the locality and analyticity of the crossing symmetric dispersion relation (CSDR). Imposing locality constraints on the CSDR gives rise to a local and fully crossing symmetric expansion of scattering amplitudes, dubbed as Feynman block expansion. A general formula is provided for the contact terms that emerge from the expansion. The analyticity domain of the expansion is also derived analogously to the Lehmann-Martin ellipse. Our observation of type-II super-string tree amplitude suggests that the Feynman block expansion has a bigger analyticity domain and better convergence.

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Debapriyo Chowdhury, Parthiv Haldar, Ahmadullah Zahed. 2022-05-27. Locality and Analyticity of the Crossing Symmetric Dispersion Relation. https://doi.org/10.1007/jhep10(2022)180

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