Appears in collection : Combinatorics and Arithmetic for Physics : Special Days

The amplituhedron is the image of the positive Grassmannian under a map in- duced by a totally positive matrix. It was introduced by Arkani-Hamed and Trnka to compute scattering amplitudes in N=4 super Yang Mills. I’ll give a gentle introduction to the amplituhedron, surveying its connections to cluster algebras, matroids, and combinatorics (Eulerian numbers, Narayana numbers, etc)