506 citations · 1.1k across the 47 of their papers we have counts for
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Scattering Amplitudes and the Positive Grassmannian
Nima Arkani-Hamed, Jacob L. Bourjaily, Freddy Cachazo +3
We establish a direct connection between scattering amplitudes in planar four-dimensional theories and a remarkable mathematical structure known as the positive Grassmannian. The c…
Two counterexamples for power ideals of arrangements
Federico Ardila, Alex Postnikov
We disprove Holtz and Ron's conjecture that the power ideal C_{A,-2} of a hyperplane arrangement A (also called the "internal zonotopal space") is generated by A-monomials. We also…
Schur times Schubert via the Fomin-Kirillov algebra
Karola Meszaros, Greta Panova, Alexander Postnikov
We study multiplication of any Schubert polynomial by a Schur polynomial (the Schubert polynomial of a Grassmannian permutation) and the expansion of this pr…
Alcoved Polytopes II
Thomas Lam, Alexander Postnikov
This is the second of two papers where we study polytopes arising from affine Coxeter arrangements. Our results include a formula for their volumes, and also compatible definitions…