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The EFT-hedron

Arkani-Hamed, Nima and Huang, Tzu-Chen and Huang, Yu-tin (2021) The EFT-hedron. Journal of High Energy Physics, 2021 (5). Art. No. 259. ISSN 1126-6708. doi:10.1007/JHEP05(2021)259.

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We re-examine the constraints imposed by causality and unitarity on the low-energy effective field theory expansion of four-particle scattering amplitudes, exposing a hidden “totally positive” structure strikingly similar to the positive geometries associated with grassmannians and amplituhedra. This forces the infinite tower of higher-dimension operators to lie inside a new geometry we call the “EFT-hedron”. We initiate a systematic investigation of the boundary structure of the EFT-hedron, giving infinitely many linear and non-linear inequalities that must be satisfied by the EFT expansion in any theory. We illustrate the EFT-hedron geometry and constraints in a wide variety of examples, including new consistency conditions on the scattering amplitudes of photons and gravitons in the real world.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Huang, Tzu-Chen0000-0002-8738-7695
Huang, Yu-tin0000-0002-3554-7765
Additional Information:© 2021 The Authors. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited. Article funded by SCOAP3. Received: April 11, 2021; Accepted: April 19, 2021; Published: May 27, 2021. We thank Alex Postnikov, Steven Karp and Congkao Wen for stimulating discussions. We thank Zvi Bern, Alexander Zhiboedov, and Dimitrios Kosmopoulos for discussions, and for pointing out an error in the spinning residue polynomials given in the first version of the paper. N.A-H. is supported by DOE grant de-sc0009988. Y-t H is supported by MoST Grant No. 106-2628-M-002-012-MY3. T-c H is supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award Number DESC0011632.
Group:Walter Burke Institute for Theoretical Physics
Funding AgencyGrant Number
Department of Energy (DOE)DE-SC0009988
Ministry of Science and Technology (Taipei)106-2628-M-002-012-MY3
Department of Energy (DOE)DE-SC0011632
Subject Keywords:Effective Field Theories, Scattering Amplitudes
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Issue or Number:5
Record Number:CaltechAUTHORS:20210107-151727295
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Official Citation:Arkani-Hamed, N., Huang, TC. & Huang, Yt. The EFT-hedron. J. High Energ. Phys. 2021, 259 (2021).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:107377
Deposited By: Joy Painter
Deposited On:08 Jan 2021 17:12
Last Modified:27 May 2021 23:01

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