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Related papers: Notes on exotic and perverse-coherent sheaves

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Let X be an algebraic variety with an action of an algebraic group G. Suppose X has a full exceptional collection of sheaves, and these sheaves are invariant under the action of the group. We construct a semiorthogonal decomposition of…

Algebraic Geometry · Mathematics 2015-05-13 Alexei Elagin

We consider the category $\operatorname{Qcoh}\mathbb{X}$ of quasicoherent sheaves where $\mathbb{X}$ is a weighted noncommutative regular projective curve over a field $k$. This category is a hereditary, locally noetherian Grothendieck…

Representation Theory · Mathematics 2020-09-28 Dirk Kussin , Rosanna Laking

The main goal of this paper is to study some local and global properties of secant varieties of algebraic curves. These results complement our previous work [8] by addressing issues given therein and providing solutions to problems raised…

Algebraic Geometry · Mathematics 2026-04-30 Lawrence Ein , Wenbo Niu , Jinhyung Park

In characteristic zero, Bezrukavnikov has shown that the category of perverse coherent sheaves on the nilpotent cone of a simply connected semisimple algebraic group is quasi-hereditary, and that it is derived-equivalent to the category of…

Representation Theory · Mathematics 2011-09-14 Pramod N. Achar

Consider cotangent bundles of exotic spheres, with their canonical symplectic structure. They admit automorphisms which preserve the part at infinity of one fibre, and which are analogous to the square of a Dehn twist. Pursuing that…

Symplectic Geometry · Mathematics 2015-05-27 Paul Seidel

Bezrukavnikov (later together with Arinkin) recovered the work of Deligne defining perverse $t$-structures for the derived category of coherent sheaves on a projective variety. In this text we prove that these $t$-structures can be obtained…

Representation Theory · Mathematics 2013-08-08 Jorge Vitoria

The purpose of this article is to set foundations for decomposition numbers of perverse sheaves, to give some methods to calculate them in simple cases, and to compute them concretely in two situations: for a simple (Kleinian) surface…

Algebraic Geometry · Mathematics 2013-09-24 Daniel Juteau

We give a complete quiver description of the category of perverse sheaves on Hermitian symmetric spaces in types A and D, constructible with respect to the Schubert stratification. The calculation is microlocal, and uses the action of the…

Algebraic Geometry · Mathematics 2007-05-23 Tom Braden

In this article we address the length of perverse sheaves arising as direct images of rank one local systems on complements of hyperplane arrangements. In the case of a cone over an essential line arrangement with at most triple points, we…

Algebraic Topology · Mathematics 2019-09-10 Nero Budur , Yongqiang Liu

We briefly introduce the theory of perverse sheaves with special attention to the topological situation where strata can have odd dimension. This is part of a project to use perverse sheaves on the topological reductive Borel-Serre…

Algebraic Geometry · Mathematics 2016-12-06 Leslie Saper

Let $\mathbf{G}$ be a connected reductive group over an algebraically closed field $\mathbb{F}$ of good characteristic, satisfying some mild conditions. In this paper we relate tilting objects in the heart of Bezrukavnikov's exotic…

Representation Theory · Mathematics 2016-07-01 Carl Mautner , Simon Riche

We give a short and self-contained proof of the Decomposition Theorem for the non-small resolution of a Special Schubert variety. We also provide an explicit description of the perverse cohomology sheaves. As a by-product of our approach,…

Algebraic Geometry · Mathematics 2019-10-28 Davide Franco

We give an explicit construction of the stack of microlocal perverse sheaves on the projective cotangent bundle of a complex manifold. Microlocal perverse sheaves will be represented as complexes of analytic ind-sheaves which have recently…

Algebraic Geometry · Mathematics 2007-05-23 Ingo Waschkies

Model-theoretic aspects of exotic smoothness were studied long ago uncovering unexpected relations to noncommutative spaces and quantum theory. Some of these relations were worked out in detail in later work. An important point in the…

Mathematical Physics · Physics 2016-02-09 Jerzy Król

Kato's exotic nilpotent cone was introduced as a substitute for the ordinary nilpotent cone of type C with cleaner properties. The geometric Robinson-Schensted correspondence is obtained by parametrizing the irreducible components of the…

Representation Theory · Mathematics 2021-03-10 Vinoth Nandakumar , Daniele Rosso , Neil Saunders

String consistency conditions are stronger than anomaly cancellation and can require the addition of exotics in the visible sector. We study such exotics and demonstrate that they may account for the modest excess at $750$ GeV in recent…

High Energy Physics - Phenomenology · Physics 2016-11-03 Mirjam Cvetič , James Halverson , Paul Langacker

We introduce irregular constructible sheaves, which are $\mathbb{C}$-constructible with coefficients in a finite version of Novikov ring $\Lambda$ and special gradings. We show that the bounded derived category of cohomologically irregular…

Complex Variables · Mathematics 2021-07-01 Tatsuki Kuwagaki

We relate shuffle algebras, as defined by Nichols, Feigin-Odesskii and Rosso, to perverse sheaves on symmetric products of the complex line (i.e., on the spaces of monic polynomials stratified by multiplicities of roots). More precisely, we…

Algebraic Topology · Mathematics 2020-01-14 Mikhail Kapranov , Vadim Schechtman

We revisit curious objects in string and M-theory called exotic brane---objects that are highly non-perturbative, possessing a tension that scales less than $g_s^{-2}$ and are generically of low-codimension. They are non-geometric in the…

High Energy Physics - Theory · Physics 2019-03-26 Ray Otsuki , David S. Berman , Edvard T. Musaev

We study non-commutative projective lines over not necessarily algebraic bimodules. In particular, we give a complete description of their categories of coherent sheaves and show they are derived equivalent to certain bimodule species. This…

Representation Theory · Mathematics 2015-10-16 D. Chan , A. Nyman