Unitarity of bespoke amplitudes

Journal Article · Mon Nov 25 00:00:00 EST 2024 · Physical Review. D.

DOI:https://doi.org/10.1103/physrevd.110.106016· OSTI ID:2478756

Bhardwaj, Rishabh ^[1]; Spradlin, Marcus ^[2]; Volovich, Anastasia ^[2]; Weng, He-Chen ^[1]

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1. Brown University, Providence, RI (United States)
2. Brown University, Providence, RI (United States); Harvard University, Cambridge, MA (United States)

We use partial wave unitarity to constrain various bespoke four-point amplitudes. We start by constructing bespoke generalizations of the type-I superstring amplitude, which we show satisfy dual resonance and have suitable high-energy limits. By analyzing the behavior of partial wave coefficients for highly massive states, we strictly rule out all bespoke amplitudes with asymptotically nonlinear Regge trajectories and place constraints on the first few nontrivial parameters in asymptotically linear cases. Finally, we argue that while a large class of unitary bespoke amplitudes fails to satisfy Regge sum rules, there exists a smaller subclass with a vanishing mass gap that is superpolynomially bounded.

• Research Organization: Brown University, Providence, RI (United States)
• Sponsoring Organization: Simons Investigator; USDOE; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: SC0010010
• OSTI ID: 2478756
• Alternate ID(s): OSTI ID: 2478483
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 10 Vol. 110; ISSN 2470-0010
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
Field & string theory models & techniques
Scattering amplitudes