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Related papers: Singular symplectic flops and Ruan cohomology

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We construct the symplectic resolution of a symplectic orbifold whose isotropy locus consists of disjoint submanifolds with homogeneous isotropy, that is, all its points have the same isotropy groups.

Symplectic Geometry · Mathematics 2020-10-19 Vicente Muñoz , Juan Angel Rojo

In this article, we study the Hamiltonian dynamics on singular symplectic manifolds and prove the Arnold conjecture for a large class of $b^m$-symplectic manifolds. Novel techniques are introduced to associate smooth symplectic forms to the…

Symplectic Geometry · Mathematics 2025-09-01 Joaquim Brugués , Eva Miranda , Cédric Oms

We prove that every non-degenerate Reeb flow on a closed contact manifold $M$ admitting a strong symplectic filling $W$ with vanishing first Chern class carries at least two geometrically distinct closed orbits provided that the positive…

Symplectic Geometry · Mathematics 2021-07-01 Miguel Abreu , Jean Gutt , Jungsoo Kang , Leonardo Macarini

We study the geometry of manifolds carrying symplectic pairs consisting of two closed 2-forms of constant ranks, whose kernel foliations are complementary. Using a variation of the construction of Boothby and Wang we build…

Symplectic Geometry · Mathematics 2007-05-23 G. Bande , D. Kotschick

Polyfold theory, as developed by Hofer, Wysocki, and Zehnder, is a relatively new approach to resolving transversality issues that arise in the study of $J$-holomorphic curves in symplectic geometry. This approach has recently led to a…

Symplectic Geometry · Mathematics 2020-01-01 Wolfgang Schmaltz

We introduce the notion of regular symplectomorphism and graded regular symplectomorphism between singular phase spaces. Our main concern is to exhibit examples of unitary torus representations whose symplectic quotients cannot be graded…

Symplectic Geometry · Mathematics 2013-04-15 Carla Farsi , Hans-Christian Herbig , Christopher Seaton

This is a write-up of my talk at the Conference on algebraic structures in Montreal, July 2003. I try to give a brief informal introduction to the proof of Y. Ruan's conjecture on orbifold cohomology multiplication for symplectic quotient…

Algebraic Geometry · Mathematics 2007-05-23 D. Kaledin

Ruan-Tian deformations of the Cauchy-Riemann operator enable a geometric definition of (standard) Gromov-Witten invariants of semi-positive symplectic manifolds in arbitrary genera. We describe an analogue of these deformations compatible…

Symplectic Geometry · Mathematics 2017-01-06 A. Zinger

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

Suppose that two compact manifolds $X, X'$ are connected by a sequence of Mukai flops. In this paper, we construct a ring isomorphism between cohomology ring of $X$ and $X'$. Using the local mirror symmetry technique, we prove that the…

Algebraic Geometry · Mathematics 2007-05-23 Jianxun Hu , Wanchuan Zhang

In this paper we analyze six examples of birational transformations between toric orbifolds: three crepant resolutions, two crepant partial resolutions, and a flop. We study the effect of these transformations on genus-zero Gromov-Witten…

Algebraic Geometry · Mathematics 2008-04-17 Tom Coates

In this paper, we propose a definition of genus one real Gromov-Witten invariants for certain symplectic manifolds with real a structure, including Calabi-Yau threefolds, and use equivariant localization to calculate certain genus one real…

Symplectic Geometry · Mathematics 2016-08-02 Mohammad Farajzadeh Tehrani

We study symplectic geometry of rationally connected $3$-folds. The first result shows that rationally connectedness is a symplectic deformation invariant in dimension $3$. If a rationally connected $3$-fold $X$ is Fano or $b_2(X)=2$, we…

Algebraic Geometry · Mathematics 2019-12-19 Zhiyu Tian

The natural sum operation for symplectic manifolds is defined by gluing along codimension two submanifolds. Specifically, let X be a symplectic 2n-manifold with a symplectic (2n-2)-submanifold V. Given a similar pair (Y,W) with a symplectic…

Symplectic Geometry · Mathematics 2007-05-23 Eleny-Nicoleta Ionel , Thomas H. Parker

In this article we give formulas for the Riemann-Roch number of a symplectic quotient arising as the reduced space corresponding to a coadjoint orbit (for an orbit close to 0) as an evaluation of cohomology classes over the reduced space at…

Symplectic Geometry · Mathematics 2007-05-23 Mark Hamilton , Lisa Jeffrey

In this paper, we shall prove that any two (projective) symplectic resolutions of a nilpotent orbit closure in a classical simple Lie algebra are connected by a finite sequence of diagrams which are locally trivial families of Mukai flops…

Algebraic Geometry · Mathematics 2007-05-23 Yoshinori Namikawa

We give a classification of generic coadjoint orbits for the groups of symplectomorphisms and Hamiltonian diffeomorphisms of a closed symplectic surface. We also classify simple Morse functions on symplectic surfaces with respect to actions…

Symplectic Geometry · Mathematics 2016-03-30 Anton Izosimov , Boris Khesin , Mehdi Mousavi

Let $G$ be a finite group and $\Y$ a $G$-gerbe over an orbifold $\B$. A disconnected orbifold $\hat{\Y}$ and a flat U(1)-gerbe $c$ on $\hat{\Y}$ is canonically constructed from $\Y$. Motivated by a proposal in physics, we study a…

Algebraic Geometry · Mathematics 2014-03-18 Xiang Tang , Hsian-Hua Tseng

Homogeneous compatible almost complex structures on symplectic manifolds are studied, focusing on those which are special, meaning that their Chern-Ricci form is a multiple of the symplectic form. Non Chern-Ricci flat ones are proven to be…

Symplectic Geometry · Mathematics 2019-12-02 Alberto Della Vedova

We make explicit computations in the formal symplectic geometry of Kontsevich and determine the Euler characteristics of the three cases, namely commutative, Lie and associative ones, up to certain weights.From these, we obtain some…

Algebraic Topology · Mathematics 2015-04-14 Shigeyuki Morita , Takuya Sakasai , Masaaki Suzuki