English
Related papers

Related papers: Non-Hamiltonian actions with isolated fixed points

200 papers

Let $\text{Ham(M)}$ be the group of Hamiltonian symplectomorphisms of a quantizable, compact, symplectic manifold $(M,\omega)$. We prove the existence of an action integral around loops in $\text{Ham(M)}$, and determine the value of this…

Symplectic Geometry · Mathematics 2007-05-23 Andrés Viña

Examples of nonformal simply connected symplectic manifolds are constructed.

Symplectic Geometry · Mathematics 2007-05-23 Ivan K. Babenko , Iskander A. Taimanov

Many of the existing results for closed Hamiltonian G-manifolds are based on the analysis of the corresponding Hamiltonian functions using Morse-Bott techniques. In general such methods fail for non-compact manifolds or for manifolds with…

Symplectic Geometry · Mathematics 2026-05-05 Aleksandra Marinković , Klaus Niederkrüger-Eid

A simple Hamiltonian manifold is a closed connected symplectic manifold equipped with a Hamiltonian action of a torus T with moment map Phi: M-->t^*, such that the fixed set M^T has exactly two connected components, denoted M_0 and M_1. We…

Symplectic Geometry · Mathematics 2013-08-14 Jean-Claude Hausmann , Tara S. Holm

Following the idea of Lusztig, Atiyah-Hirzebruch and Kosniowski, we note that the Dolbeault-type operators on compact, almost-complex manifolds are rigid. When the circle action has isolated fixed points, this rigidity result will produce…

Symplectic Geometry · Mathematics 2018-10-18 Ping Li

We consider compact connected six dimensional symplectic manifolds with Hamiltonian SU(2) or SO(3) actions with cyclic principal stabilizers. We classify such manifolds up to equivariant symplectomorphisms.

Symplectic Geometry · Mathematics 2007-05-23 River Chiang

This paper expands some of the issues of the paper math.SG/0506449. We introduce a new technique to produce symplectic manifolds, by taking a symplectic non-free action of a finite group on a symplectic manifold and resolving symplectically…

Symplectic Geometry · Mathematics 2007-05-23 Marisa Fernández , Vicente Muñoz

We construct a compact symplectic manifold with a Hamiltonian circle action for which the Duistermaat-Heckman function is not log-concave.

dg-ga · Mathematics 2008-02-03 Yael Karshon

Let $(M,\omega_M)$ be a six dimensional closed monotone symplectic manifold admitting an effective semifree Hamiltonian $S^1$-action. We show that $(M,\omega_M)$ is $S^1$-equivariant symplectomorphic to some K\"{a}hler Fano manifold…

Symplectic Geometry · Mathematics 2020-01-01 Yunhyung Cho

In this paper we study the size of the fixed point set of a Hamiltonian diffeomorphism on a closed symplectic manifold which is both rational and weakly monotone. We show that there exists a non-trivial cycle of fixed points whenever the…

Symplectic Geometry · Mathematics 2013-05-22 Wyatt Howard

We give examples of symplectic actions of a cyclic group, inducing a trivial action on homology, on four-manifolds that admit Hamiltonian circle actions, and show that they do not extend to Hamiltonian circle actions. Our work applies…

Symplectic Geometry · Mathematics 2019-03-28 River Chiang , Liat Kessler

We study the problem of determining which diffeomorphism classes of K\"{a}hler manifolds admit a Hamiltonian circle action. Our main result is the following: Let $M$ be a closed symplectic manifold, diffeomorphic to a complete intersection…

Symplectic Geometry · Mathematics 2022-03-14 Nicholas Lindsay

For a circle action on a compact almost complex manifold with a fixed point, the lower bound on the number of fixed points is known in dimension up to 12 except 10. In this paper, we show that if the circle group acts on a 10-dimensional…

Algebraic Topology · Mathematics 2026-02-03 Donghoon Jang

We exhibit many examples of closed symplectic manifolds on which there is an autonomous Hamiltonian whose associated flow has no nonconstant periodic orbits (the only previous explicit example in the literature was the torus T^2n (n\geq 2)…

Symplectic Geometry · Mathematics 2014-09-10 Michael Usher

Let $(M,\omega)$ be a ruled symplectic four-manifold. If $(M, \omega)$ is rational, then every homologically trivial symplectic cyclic action on $(M,\omega)$ is the restriction of a Hamiltonian circle action.

Symplectic Geometry · Mathematics 2019-03-28 River Chiang , Liat Kessler

For every compact almost complex manifold (M,J) equipped with a J-preserving circle action with isolated fixed points, a simple algebraic identity involving the first Chern class is derived. This enables us to construct an algorithm to…

Symplectic Geometry · Mathematics 2012-06-15 Leonor Godinho , Silvia Sabatini

A study of symplectic actions of a finite group $G$ on smooth 4-manifolds is initiated. The central new idea is the use of $G$-equivariant Seiberg-Witten-Taubes theory in studying the structure of the fixed-point set of these symmetries.…

Geometric Topology · Mathematics 2007-09-12 Weimin Chen , Slawomir Kwasik

This paper is devoted to the study of symplectic manifolds and their connection with Hamiltonian dynamical systems. We review some properties and operations on these manifolds and see how they intervene when studying the complete…

Symplectic Geometry · Mathematics 2019-04-03 A. Lesfari

A trivial bundle of regular connected invariant manifolds of a completely integrable Hamiltonian system can be provided with action-angle coordinates.

Symplectic Geometry · Mathematics 2007-05-23 E. Fiorani , G. Giachetta , G. Sardanashvily

This note describes some recent results about the homotopy properties of Hamiltonian loops in various manifolds, including toric manifolds and one point blow ups. We describe conditions under which a circle action does not contract in the…

Symplectic Geometry · Mathematics 2009-01-18 Dusa McDuff