Abstract

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.

Details

Title
The EFT-hedron
Author
Arkani-Hamed Nima 1 ; Tzu-Chen, Huang 2 ; Yu-tin, Huang 3 

 Institute for Advanced Study, School of Natural Sciences, Princeton, USA (GRID:grid.78989.37) (ISNI:0000 0001 2160 7918) 
 California Institute of Technology, Walter Burke Institute for Theoretical Physics, Pasadena, USA (GRID:grid.20861.3d) (ISNI:0000000107068890) 
 National Taiwan University, Department of Physics and Astronomy, Taipei, Taiwan (GRID:grid.19188.39) (ISNI:0000 0004 0546 0241); National Tsing-Hua University, Physics Division, National Center for Theoretical Sciences, Hsinchu, Taiwan (GRID:grid.38348.34) (ISNI:0000 0004 0532 0580) 
Publication year
2021
Publication date
May 2021
Publisher
Springer Nature B.V.
e-ISSN
10298479
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2533055912
Copyright
© The Author(s) 2021. This work is published under CC-BY 4.0 (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.