PIRSA:26040101

Video URL

https://pirsa.org/26040101

Combinatorics and Geometry of the Amplituhedron

Sherman-Bennett, M. (2026). Combinatorics and Geometry of the Amplituhedron. Perimeter Institute for Theoretical Physics. https://pirsa.org/26040101

Sherman-Bennett, Melissa. Combinatorics and Geometry of the Amplituhedron. Perimeter Institute for Theoretical Physics, Apr. 24, 2026, https://pirsa.org/26040101 

          @misc{ scivideos_PIRSA:26040101,
            doi = {10.48660/26040101},
            url = {https://pirsa.org/26040101},
            author = {Sherman-Bennett, Melissa},
            keywords = {Mathematical physics},
            language = {en},
            title = {Combinatorics and Geometry of the Amplituhedron},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2026},
            month = {apr},
            note = {PIRSA:26040101 see, \url{https://scivideos.org/pirsa/26040101}}
          }

Melissa Sherman-Bennett University of California, Davis

Talk numberPIRSA:26040101
DOI10.48660/26040101
Source RepositoryPIRSA
Collection
Talk Type Scientific Series
Subject

Abstract

The amplituhedron was introduced by Arkani-Hamed and Trnka as a geometric object which "encodes" scattering amplitudes in N=4 SYM theory. One of their motivations was the Britto-Cachazo-Feng-Witten (BCFW) recursion for amplitudes, which in particular produced many different formulas for the same amplitude. Their expectation was that the amplitude is the "volume" of the amplituhedron, and the different BCFW formulas correspond to different ways of decomposing the amplituhedron into small pieces. This expectation is in fact correct. I'll discuss some of the mathematics going into the proof, some unexpected phenomena arising along the way, and some lingering questions. This is joint work with (various subsets of) Chaim Even-Zohar, Tsviqa Lakrec, Matteo Parisi, Ran Tessler, and Lauren Williams.