dc.contributor.author Davighi, J dc.contributor.author Melville, S dc.contributor.author You, T dc.date.accessioned 2022-05-27T16:08:37Z dc.date.available 2022-05-27T16:08:37Z dc.date.issued 2022 dc.date.submitted 2021-08-30 dc.identifier.issn 1029-8479 dc.identifier.other jhep02(2022)167 dc.identifier.other 17852 dc.identifier.uri https://www.repository.cam.ac.uk/handle/1810/337558 dc.description.abstract We derive new effective field theory (EFT) positivity bounds on the elastic $2\to2$ scattering amplitudes of massive spinning particles from the standard UV properties of unitarity, causality, locality and Lorentz invariance. By bounding the $t$ derivatives of the amplitude (which can be represented as angular momentum matrix elements) in terms of the total ingoing helicity, we derive stronger unitarity bounds on the $s$- and $u$-channel branch cuts which determine the dispersion relation. In contrast to previous positivity bounds, which relate the $t$-derivative to the forward-limit EFT amplitude with no $t$ derivatives, our bounds establish that the $t$-derivative alone must be strictly positive for sufficiently large helicities. Consequently, they provide stronger constraints beyond the forward limit and can be used to constrain dimension-6 interactions with a milder assumption about the high-energy growth of the UV amplitude. dc.language en dc.publisher Springer Science and Business Media LLC dc.subject Regular Article - Theoretical Physics dc.subject Effective Field Theories dc.subject Scattering Amplitudes dc.title Natural selection rules: new positivity bounds for massive spinning particles dc.type Article dc.date.updated 2022-05-27T16:08:36Z prism.issueIdentifier 2 prism.publicationName Journal of High Energy Physics prism.volume 2022 dc.identifier.doi 10.17863/CAM.84967 dcterms.dateAccepted 2022-01-27 rioxxterms.versionofrecord 10.1007/JHEP02(2022)167 rioxxterms.version VoR rioxxterms.licenseref.uri http://creativecommons.org/licenses/by/4.0/ dc.contributor.orcid Melville, S [0000-0003-3516-856X] dc.identifier.eissn 1029-8479 pubs.funder-project-id EPSRC (EP/T017481/1) cam.issuedOnline 2022-02-21 dc.identifier.arxiv 2108.06334
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