Title: Combinatorics of the amplituhedron
Speaker: Steven Karp (University of Michigan)
Abstract: The tree amplituhedron A(n,k,m) is a geometric object introduced by Arkani-Hamed and Trnka in 2013, in their study of scattering amplitudes in high-energy physics. I will introduce the amplituhedron and describe how it generalizes objects such as cyclic polytopes, cyclic hyperplane arrangements, and positive Grassmannians. I will discuss the problem of triangulating amplituhedra, which involves the combinatorics of Catalan objects and, conjecturally, plane partitions. This is joint work with Lauren Williams and Yan Zhang. I will also discuss recent work about the topology of amplituhedra and positive Grassmannians, which is joint with Pavel Galashin and Thomas Lam.
Seminar URL: https://research.math.osu.edu/gcis/