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Related papers: Flops and about: a guide

200 papers

We prove that any symplectic resolution of the closure of a nilpotent orbit in a semi-simple complex Lie algebra is isomorphic to the collapsing of the cotangent bundle of a projective homogenous variety. Then we give a complete…

Algebraic Geometry · Mathematics 2015-06-26 Baohua Fu

We obtain structure results for locally conformally symplectic Lie algebras. We classify locally conformally symplectic structures on four-dimensional Lie algebras and construct locally conformally symplectic structures on compact quotients…

Differential Geometry · Mathematics 2023-06-13 Daniele Angella , Giovanni Bazzoni , Maurizio Parton

Flops are birational transformations which, conjecturally, induce derived equivalences. In many cases an equivalence can be produced as pull-push via a resolution of the birational transformation; when this happens, we have a non-trivial…

Algebraic Geometry · Mathematics 2021-11-03 Federico Barbacovi

Using Morita type stratifications, we establish a one-to-one correspondence between geometric vector fields on a separated differentiable stack and stratified vector fields on its orbit space. This correspondence enables us to derive a…

Differential Geometry · Mathematics 2026-05-06 Mateus de Melo , Juan Sebastian Herrera-Carmona , Fabricio Valencia

Using the symplectic geometry of certain manifolds which appear naturally in Lie theory, we define an invariant which assigns a graded abelian group to an oriented link. The relevant manifolds are transverse slices to certain nilpotent…

Symplectic Geometry · Mathematics 2007-05-23 Paul Seidel , Ivan Smith

Let $G$ be a simply connected algebraic group of type $B,C$ or $D$ over an algebraically closed field of characteristic 2. We construct a Springer correspondence for the dual vector space of the Lie algebra of $G$. In particular, we…

Representation Theory · Mathematics 2018-05-28 Ting Xue

We exhibit many examples of closed complex surfaces whose diffeomorphism groups are not simply-connected and contain loops that are not homotopic to loops of symplectomorphisms.

Differential Geometry · Mathematics 2022-06-29 Gleb Smirnov

The condition of nilpotency is studied in the general linear Lie algebra $\mathfrak{gl}_{n}(\mathbb{K})$ and the symplectic Lie algebra $\mathfrak{sp}_{2m}(\mathbb{K})$ over an algebraically closed field of characteristic 0. In particular,…

Algebraic Geometry · Mathematics 2014-03-14 Samuel Reid

Every symplectic Lie algebra with degenerate (including non-abelian nilpotent symplectic Lie algebras) has the structure of a quadratic extension. We give a standard model and describe the equivalence classes on the level of corresponding…

Differential Geometry · Mathematics 2016-09-13 Mathias Fischer

We give an equivalence of triangulated categories between the derived category of finitely generated representations of symplectic reflection algebras associated with wreath products (with parameter t=0) and the derived category of coherent…

Representation Theory · Mathematics 2007-05-23 Iain Gordon , S. Paul Smith

We introduce a new class of autoequivalences that act on the derived categories of certain vector bundles over Grassmannians. These autoequivalences arise from Grassmannian flops: they generalize Seidel-Thomas spherical twists, which can be…

Algebraic Geometry · Mathematics 2019-02-20 Will Donovan , Ed Segal

Each choice of a K\"ahler class on a compact complex manifold defines an action of the Lie algebra $\slt$ on its total complex cohomology. If a nonempty set of such K\"ahler classes is given, then we prove that the corresponding…

alg-geom · Mathematics 2009-10-28 Eduard Looijenga , Valery L. Lunts

This is a short presentation of some classical results on finite dimensional complex Lie algebras (classification of nilpotent Lie algebras, deformations and perturbations, contractions and rigidity). We present some applications to…

Rings and Algebras · Mathematics 2008-05-06 Michel Goze

Recently, Segal constructed a derived equivalence for an interesting 5-fold flop that was provided by Abuaf. The aim of this article is to add some results for the derived equivalence for Abuaf's flop. Concretely, we study the equivalence…

Algebraic Geometry · Mathematics 2024-04-26 Wahei Hara

The notion of a holomorphically symplectic manifold can be generalized to the singular one. This paper studies the birational contraction maps between symplectic varieties, and then describes the deformation of a symplectic variety which…

Algebraic Geometry · Mathematics 2007-05-23 Yoshinori Namikawa

We show that for smooth complex projective varieties the most general combinations of chern numbers that are invariant under the K-equivalence relation consist of the complex elliptic genera. Combined with a recent result of Totaro, we…

Algebraic Geometry · Mathematics 2011-10-11 Chin-Lung Wang

We study symplectic (contact) structures on nilmanifolds that correspond to the filiform Lie algebras - nilpotent Lie algebras of the maximal length of the descending central sequence. We give a complete classification of filiform Lie…

Rings and Algebras · Mathematics 2007-05-23 Dmitri V. Millionschikov

This short note is a supplement to the previous article with the same title. Here we treat a conical symplectic variety obtained as a finite covering of a (not necessarily normal) nilpotent orbit closure of a complex semisimple Lie algebra.

Algebraic Geometry · Mathematics 2017-07-11 Yoshinori Namikawa

Finite-order invariants of knots in arbitrary 3-manifolds (including non-orientable ones) are constructed and studied by methods of the topology of discriminant sets. Obstructions to the integrability of admissible weight systems to…

Geometric Topology · Mathematics 2016-09-07 Victor A. Vassiliev

We study the birational geometry of irreducible holomorphic symplectic varieties arising as varieties of lines of general cubic fourfolds containing a cubic scroll. We compute the ample and moving cones, and exhibit a birational…

Algebraic Geometry · Mathematics 2008-05-28 Brendan Hassett , Yuri Tschinkel