Witten diagrams in momentum space and one graviton exchange between scalars in Weyl invariant unimodular gravity

J. Anero; Carmelo P. Martin

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arXiv · 2410.07365

Witten diagrams in momentum space and one graviton exchange between scalars in Weyl invariant unimodular gravity

J. Anero·Carmelo P. Martin

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Abstract

We tackle head-on the computation of the $s$-channel Witten diagram in momentum space corresponding to the exchange of a graviton between minimally coupled scalars in Weyl invariant unimodular gravity. By means of a lengthy calculation, we show first that the value of the diagram in question is the same as in General Relativity and, then, we obtain a compact expression for it in terms of the Mandelstam variables.

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J. Anero, Carmelo P. Martin. 2024-10-09. Witten diagrams in momentum space and one graviton exchange between scalars in Weyl invariant unimodular gravity. https://arxiv.org/abs/2410.07365

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