Search arXivSearch

arXiv · 2512.03893

Topological Obstructions to Dynamical Convexity

Abstract

We study the topological obstructions of dynamical convexity on contact manifolds focusing on fillability by cotangent bundles and subcritical surgeries. Using links to algebraic geometry, we motivate and define a stronger version of dynamical convexity, and investigate the topology of these manifolds. More precisely, we show that strongly dynamically convex contact manifolds cannot arise as a unit cotangent bundle $(ST^*M,λ_{std})$ of a closed manifold $M$ and in particular that simply connected dynamically convex contact manifolds cannot be filled by cotangent bundles. We demonstrate that dynamical convexity can be used to recover homotopy groups of topologically simple fillings with vanishing symplectic homology. We also show obstructions to dynamical convexity that come from studying different kinds of subcritical surgeries.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Shahnaz Shamim Shahul. 2026-02-20. Topological Obstructions to Dynamical Convexity. https://arxiv.org/abs/2512.03893

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

KEEP EXPLORING

Related papers

An algebraic generalization of Giroux's criterion

We compute the contact homology algebra of a neighborhood $(\mathbb{R}_τ \times W, ξ)$ of a convex hypersurface $W$ and determine when this algebra is zero or non-zero. Thus we provide a tool for inferring the tightness of such $ξ$ for $W$ of any even dimension. In more detail, consider the augmentations $ε^{\pm}$ of chain-level contact homology algebras of the dividing set $(Γ, ξ_Γ)$ determined by the positive and negative regions of $W$. We compute $CH(\mathbb{R}_τ \times W, ξ)$ as the derived tensor product of the $ε^{\pm}$. Consequently the vanishing or non-vanishing of $CH(\mathbb{R}_τ \times W, ξ)$ is determined by the induced morphisms $Hε^{\pm}$ from $CH(Γ, ξ_Γ)$ to the coefficient ring.

math.SG

Hofer-Like Geometry Revisited

We prove that the inclusion of the Hamiltonian group $\Ham(M,ω)$ into the identity component \(G_ω(M)\) of the symplectic diffeomorphism group is a bi-Lipschitz embedding with respect to the Hofer norm and the Hofer-like norm, and we identify geometric conditions under which this embedding is isometric: settling a conjecture of Banyaga. This conjecture was proved by Buss and Leclercq; our proof provides explicit equivalence constants. We also detail and simplify Banyaga's original proof of the non-degeneracy of the Hofer-like norm. We then extend the analysis to all of \(G_ω(M)\): for \(ϕ\) with flux class \(γ\), the Hofer-like norm is given by a semidirect-product formula, the infimum over the harmonic locus \(\Harm(γ)\) plus a Hofer residue. This yields a geometric condition for the two norms to agree on the Hamiltonian group. In particular, this geometric condition holds on all closed surfaces of genus $g\ge 2$.

math.SG

Kodaira fibres and wrapped Floer cohomology

Let $F$ be a singular fibre of a relatively minimal complex elliptic fibration with smooth total space, and let $Ω$ be a nonvanishing holomorphic two-form near $F$. We show that a small neighbourhood of $F$ is a Weinstein domain for $\mathrm{Re}\,Ω$ whose completion is a Legendrian surgery, with cocores obtained by completing holomorphic disks transverse to the components of $F$. For every coefficient field and every multiplicative bulk class, we compute the wrapped Floer cohomology of these cocores and prove that it is concentrated in degree zero. The cocores generate, so the bulk-deformed wrapped Fukaya category is equivalent to the category of perfect modules over an explicit algebra: a multiplicative preprojective algebra of affine type for the normal crossing fibres, and a quiver algebra with relations for types $II$, $III$ and $IV$. Applications include formality of the affine plumbing dg algebras, mirror equivalences with resolved affine surfaces at the trivial bulk class, and with quotient stacks of algebraic tori at root-of-unity bulk classes for the four star-shaped fibres.

math.SG