activity
20132026
most citedThe totally nonnegative Grassmannian is a ball

33 citations · 284 across the 37 of their papers we have counts for

collaborators

42 papers

hep-th2026

Amplituhedra and origami, II: loop level

Pavel Galashin

Building on the recently discovered origami-amplituhedron correspondence, we prove that the BCFW (Britto-Cachazo-Feng-Witten) cells triangulate the amplituhedron in full gene…

math.AG2025

Comparing cluster algebras on braid varieties

Roger Casals, Pavel Galashin, Mikhail Gorsky +3

Braid varieties parametrize linear configurations of flags with transversality conditions dictated by positive braids. They include and generalize reduced double Bruhat cells, posi…

hep-th2024

Amplituhedra and origami, I: tree level

Pavel Galashin

We establish a precise correspondence between points of the tree momentum amplituhedron and origami crease patterns. As an application, we prove that the BCFW (Britto-Cachazo…

math.CO2023★ 2 cited

Monotone links in DAHA and EHA

Pavel Galashin, Thomas Lam

We define monotone links on a torus, obtained as projections of curves in the plane whose coordinates are monotone increasing. Using the work of Morton-Samuelson, to each monotone…

math.AG2023★ 3 cited

Braid variety cluster structures, II: general type

Pavel Galashin, Thomas Lam, Melissa Sherman-Bennett

We show that braid varieties for any complex simple algebraic group are cluster varieties. This includes open Richardson varieties inside the flag variety .

math.CO2022

Move-reduced graphs on a torus

Pavel Galashin, Terrence George

We determine which bipartite graphs embedded in a torus are move-reduced. In addition, we classify equivalence classes of such move-reduced graphs under square/spider moves. This e…

math.CO2022★ 3 cited

Braid variety cluster structures, I: 3D plabic graphs

Pavel Galashin, Thomas Lam, Melissa Sherman-Bennett +1

We introduce -dimensional generalizations of Postnikov's plabic graphs and use them to establish cluster structures for type braid varieties. Our results include known clust…

math.CO2022★ 1 cited

Plabic links, quivers, and skein relations

Pavel Galashin, Thomas Lam

We study relations between cluster algebra invariants and link invariants. First, we show that several constructions of positroid links (permutation links, Richardson links, grid d…

math.CO2022

Rational Noncrossing Coxeter-Catalan Combinatorics

Pavel Galashin, Thomas Lam, Minh-Tâm Quang Trinh +1

We solve two open problems in Coxeter-Catalan combinatorics. First, we introduce a family of rational noncrossing objects for any finite Coxeter group, using the combinatorics of d…

math.RT2022

The twist for Richardson varieties

Pavel Galashin, Thomas Lam

We construct the twist automorphism of open Richardson varieties inside the flag variety of a complex semisimple algebraic group. We show that the twist map preserves totally posit…

math.AG2021

Totally nonnegative critical varieties

Pavel Galashin

We study totally nonnegative parts of critical varieties in the Grassmannian. We show that each totally nonnegative critical variety Crit is the image of an affine poset…

math.CO2021★ 2 cited

-associahedra

Pavel Galashin

For each poset , we construct a polytope called the -associahedron. Similarly to the case of graph associahedra, the faces of correspond to certain nested colle…

math.CO2021★ 1 cited

Positroid Catalan numbers

Pavel Galashin, Thomas Lam

Given a permutation , we study the positroid Catalan number defined to be the torus-equivariant Euler characteristic of the associated open positroid variety. We introduce…

math.CO2021★ 8 cited

Critical varieties in the Grassmannian

Pavel Galashin

We introduce a family of spaces called critical varieties. Each critical variety is a subset of one of the positroid varieties in the Grassmannian. The combinatorics of positroid v…

math.CO2020★ 2 cited

Positroids, knots, and -Catalan numbers

Pavel Galashin, Thomas Lam

We relate the mixed Hodge structure on the cohomology of open positroid varieties (in particular, their Betti numbers over and point counts over ) to Kho…

math-ph2020

A formula for boundary correlations of the critical Ising model

Pavel Galashin

Given a finite rhombus tiling of a polygonal region in the plane, the associated critical -invariant Ising model is invariant under star-triangle transformations. We give a simp…

math.PR2020

Symmetries of stochastic colored vertex models

Pavel Galashin

We discover a new property of the stochastic colored six-vertex model called flip-invariance. We use it to show that for a given collection of observables of the model, any transfo…

math.CO2019★ 2 cited

Higher secondary polytopes and regular plabic graphs

Pavel Galashin, Alexander Postnikov, Lauren Williams

Given a configuration of points in , we introduce the higher secondary polytopes , which have the property that agrees…

math.CO2019★ 5 cited

Positroid varieties and cluster algebras

Pavel Galashin, Thomas Lam

We show that the coordinate ring of an open positroid variety coincides with the cluster algebra associated to a Postnikov diagram. This confirms conjectures of Postnikov, Muller--…

math.CO2019★ 32 cited

Regularity theorem for totally nonnegative flag varieties

Pavel Galashin, Steven N. Karp, Thomas Lam

We show that the totally nonnegative part of a partial flag variety (in the sense of Lusztig) is a regular CW complex, confirming a conjecture of Williams. In particular, the…

math-ph2018★ 25 cited

Ising model and the positive orthogonal Grassmannian

Pavel Galashin, Pavlo Pylyavskyy

We completely describe by inequalities the set of boundary correlation matrices of planar Ising networks embedded in a disk. Specifically, we build on a recent result of M.~Lis to…

math.GT2018

Some more amplituhedra are contractible

Pavle V. M. Blagojević, Pavel Galashin, Nevena Palić +1

The amplituhedra arise as images of the totally nonnegative Grassmannians by projections that are induced by linear maps. They were introduced in Physics by Arkani-Hamed \& Trnka (…

math.CO2018★ 27 cited

Parity duality for the amplituhedron

Pavel Galashin, Thomas Lam

The (tree) amplituhedron is a certain subset of the Grassmannian introduced by Arkani-Hamed and Trnka in 2013 in order to study scattering amplitudes in $N=…

math.CO2018★ 2 cited

Trianguloids and Triangulations of Root Polytopes

Pavel Galashin, Gleb Nenashev, Alexander Postnikov

Triangulations of a product of two simplices and, more generally, of root polytopes are closely related to Gelfand-Kapranov-Zelevinsky's theory of discriminants, to tropical geomet…