We compute the partition function on the hemisphere of a class of two-dimensional (2, 2)
supersymmetric field theories including gauged linear sigma models. The result provides a …

Given a quasiprojective algebraic variety with a reductive group action, we describe a
relationship between its equivariant derived category and the derived category of its …

We prove that the functor of noncommutative deformations of every flipping or flopping
irreducible rational curve in a 3-fold is representable, and hence, we associate to every such …

Given any toric subvariety $ Y $ of a smooth toric variety $ X $ of codimension $ k $, we
construct a length $ k $ resolution of $\mathcal O_Y $ by line bundles on $ X $. Furthermore …

In this paper we generalize standard results about non-commutative resolutions of quotient
singularities for finite groups to arbitrary reductive groups. We show in particular that …

We provide a factorization model for the continuous internal Hom, in the homotopy category
of k-linear dg-categories, between dg-categories of equivariant factorizations. This motivates …

We construct a categorification of the maximal commutative subalgebra of the type A Hecke
algebra. Specifically, we propose a monoidal functor from the (symmetric) monoidal …

Many moduli spaces are constructed as quotients of group actions; this paper surveys the
classical theory, as well as recent progress and applications. We review geometric invariant …

We formulate a theory of instability and Harder-Narasimhan filtrations for an arbitrary moduli
problem in algebraic geometry. We introduce the notion of a $\Theta $-stratification of a …

Given a quiver with potential $(Q, W) $, Kontsevich–Soibelman constructed a cohomological
Hall algebra (CoHA) on the critical cohomology of the stack of representations of $(Q, W) …