Searcharxiv⌕ Search

arXiv · math/0511194

Symplectic connections

Abstract

This article is an overview of the results obtained in recent years on symplectic connections. We present what is known about preferred connections (critical points of a variational principle). The class of Ricci-type connections (for which the curvature is entirely determined by the Ricci tensor) is described in detail, as well as its far reaching generalization to special connections. A twistorial construction shows a relation between Ricci-type connections and complex geometry. We give a construction of Ricci-flat symplectic connections. We end up by presenting, through an explicit example, an approach to noncommutative symplectic symmetric spaces.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Pierre Bieliavsky, Michel Cahen, Simone Gutt, John Rawnsley, Lorenz Schwachhofer. 2006-05-16. Symplectic connections. https://arxiv.org/abs/math/0511194

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Multiplicity Bounds for Contractible Closed Reeb Orbits on Prequantization Bundles

We study the multiplicity of contractible closed Reeb orbits on prequantization circle bundles $(M^{2n+1},ξ)$ over closed symplectic manifolds $(B^{2n},ω)$. For even $n$, under suitable geometric hypotheses, we prove that every non-degenerate contact form supporting $ξ$ whose contractible closed orbits have nonzero mean index and whose good contractible closed orbits have nonzero Conley--Zehnder index carries at least $\frac{1}{2}χ(B)+\frac{1}{2}\dim H_n(B;\mathbb{Q})+1$ geometrically distinct contractible closed Reeb orbits. In dimension five, under the corresponding geometric hypotheses and assuming $H_1(B;\mathbb{Q})=0$, we prove the conjectural lower bound $\dim H_*(B;\mathbb{Q})$ for every non-degenerate supporting contact form whose simple contractible closed orbits have nonzero Conley--Zehnder index.

math.SG↗

Categorical and Floer-theoretic entropies: comparison and counting conjugacy classes in symplectic mapping class groups

Let $W$ be a Weinstein manifold and let $f: W \to W$ be a compactly supported symplectic automorphism. Using Floer theories, one can define two different entropies of $f$, called "Floer-theoretic" entropy and "categorical" entropy. The current article compares these two entropies and show that the former bounds the latter from below. As an application of the comparison, using that these entropies are invariants up to the conjugate relation, we count conjugacy classes in symplectic mapping classes. Especially, we show an exponential abundance of conjugacy classes that are smoothly isotopic to the identity, when $W$ is a Weinstein manifold of dimension $4n \geq 6$, satisfying a local condition.

math.SG↗

Mapping-space Gromov--Witten classes and the Fano variety of lines

Let $Y$ be a smooth cubic 3-fold. We show that $S^2 \times Y$ admits an infinite sequence of cohomologous symplectic forms which are all deformation equivalent but pairwise non-isotopic; McDuff showed the corresponding result on $(S^2)^2 \times T^2$, but these appear to be the first simply-connected and monotone examples. The results are obtained from McDuff's bordism-flavoured Gromov--Witten invariant, re-interpreted cohomologically in terms of an evaluation map valued in the space of maps from the 2-sphere to a symplectic target. The application then relies on classical properties of the Fano space of lines on $Y$. We also discuss higher-dimensional generalisations.

math.SG↗