Jaroslav Trnka (UC Davis, Department of Physics and Astronomy) **

**Title: **BCFW recursion relations and non-planar positive geometry

**Abstract:** There is a close connection between the scattering amplitudes in planar N=4 SYM theory and the cells in the positive Grassmannian. In the context of BCFW recursion relations the tree-level S-matrix is represented as a sum of planar on-shell diagrams (aka plabic graphs) and associated with logarithmic forms on the Grassmannian cells of certain dimensionality. In this talk, we explore non-adjacent BCFW shifts which naturally lead to non-planar on-shell diagrams and new interesting subspaces inside the real Grassmannian.

***This talk will be hybrid. Talk will be held at CMSA (20 Garden St) Room G10.*

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