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arXiv · 2212.00764

On unitarity of the Coon amplitude

Rishabh Bhardwaj·Shounak De·Marcus Spradlin·Anastasia Volovich
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Abstract

The Coon amplitude is a one-parameter deformation of the Veneziano amplitude. We explore the unitarity of the Coon amplitude through its partial wave expansion using tools from $q$-calculus. Our analysis establishes manifest positivity on the leading and sub-leading Regge trajectories in arbitrary spacetime dimensions $D$, while revealing a violation of unitarity in a certain region of $(q,D)$ parameter space starting at the sub-sub-leading Regge order. A combination of numerical studies and analytic arguments allows us to argue for the manifest positivity of the partial wave coefficients in fixed spin and Regge asymptotics.

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Rishabh Bhardwaj, Shounak De, Marcus Spradlin, Anastasia Volovich. 2022-12-01. On unitarity of the Coon amplitude. https://arxiv.org/abs/2212.00764

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