arXiv subjects

Yoshihiro Sugimoto

Publications and source records attributed to Yoshihiro Sugimoto.

9 recordsLinked to original sources

arXiv2026

Orbifold Mapping Spaces via Bibundles

The existence of orbifold structures on mapping spaces between orbifolds was established in previous work, notably by W. Chen and B. Chen-Du-Liao. In this paper, we construct an infinite-dimensional orbifold structure on the mapping space in a more geometric way, using bibundles (or Hilsum-Skandalis morphisms), based on Lerman's description of orbifold morphisms. We construct a proper étale (or Fréchet) Lie groupoid representing the mapping space in the $C^k$, $C^\infty$, and $W^{k,p}$ settings, and show that its Morita equivalence class is independent of the choices of groupoid presentations. Locally, the mapping groupoid is isomorphic to the action groupoid of a finite group, where the finite group is identified with the automorphism group of the corresponding bibundle. This provides a concrete geometric framework for further studies of mapping spaces and moduli spaces on orbifolds, with applications to Floer theory on symplectic orbifolds.

math.SG↗

arXiv2025

On the Hofer-Zehnder conjecture for non-contractible periodic orbits in Hamiltonian dynamics

In this paper, we treat an open problem related to the number of periodic orbits of Hamiltonian diffeomorphisms on closed symplectic manifolds. Hofer-Zehnder conjecture states that a Hamiltonian diffeomorphisms has infinitely many periodic orbits if it has "homologically unnecessary periodic orbits"". For example, non-contractible periodic orbits are homologically unnecessary periodic orbits because Floer homology of non-contractible periodic orbits is trivial. We prove Hofer-Zehnder conjecture for non-contractible periodic orbits for very wide classes of symplectic manifolds.

math.SG↗

arXiv2025

Homological Lagrangian monodromy and Wang exact sequence

In this paper, we study homological monodromy of a Lagrangian submanifold. We prove that homological Lagrangian monodromy is trivial if Hofer energy of a Hamiltonian isotopy is smaller than the minimum energy of J-holomorphic spheres and discs.

math.SG↗

arXiv2023

No $C^1$-recurrence of iterations of symplectomorphisms

In this article, we study the behavior of iterations of symplectomorphisms and Hamiltonian diffeomorphisms on symplectic manifolds. We prove that symplectomorphisms and Hamiltonian diffeomorphisms do not have $C^1$-recurrence on negatively monotone symplectic manifolds. This is a generalization of the results of the study of Polterovich, Ono, Atallah-Shelukhin. Hamiltonian group actions play very important roles in symplectic geometry. We see that negatively monotone symplectic manifolds are far from being Hamiltonian $G$-manifolds.

math.SG↗

arXiv2021

On the generic Conley conjecture

In this paper, we treat an open problem related to the number of periodic orbits of Hamiltonian diffeomorphisms on closed symplectic manifolds, so-called generic Conley conjecture. Generic Conley conjecture states that generically Hamiltonian diffeomorphisms have infinitely many simple contractible periodic orbits. We prove generic Conley conjecture for very wide classes of symplectic manifolds.

math.SG↗

arXiv2019

A Comparison between Hofer's metric and C^1-topology

Hofer's metric is a bi-invariant metric on Hamiltonian diffeomorphism groups. Our main result shows that the topology induced from Hofer's metric is weaker than C^1-topology if the symplectic manifold is closed.

math.SG↗

arXiv2019

Applications of square roots of diffeomorphisms

In this paper, we prove that on any contact manifold, there exists an arbitrary C^{\infty}-small contactomorphism which does not admit a square root. In particular, there exists an arbitrary C^{\infty}-small contactomorphism which is not "autonomous". This result is the first step to study the topology of non-autonomous contactomorphisms. As an application, we also prove a similar result for the diffeomorphism group for any smooth manifold.

math.DG↗

arXiv2019

The sharp energy-capacity inequality on convex symplectic manifolds

In symplectic geometry, symplectic invariants are useful tools in studying symplectic phenomena. Hofer-Zehnder capacity and displacement energy are important symplectic invariants. Usher proved the so-called sharp energy-capacity inequality between Hofer-Zehnder capacity and the displacement energy for closed symplectic manifolds. In this paper, we extend the sharp energy-capacity inequality to convex symplectic manifolds.

math.SG↗

arXiv2018

Spectral spread and non-autonomous Hamiltonian diffeomorphisms

For any symplectic manifold, Hamiltonian diffeomorphism group contains a subset which consists of times one flows of autonomous(time-independent) Hamiltonian vector fields. Polterovich and Shelukhin proved that the complement of autonomous Hamiltonian diffeomorphisms is dense in C^/infty-topology and Hofer's metric if the symplectic manifold is closed symplectically aspherical. In this paper, we generalize above theorem to general closed symplectic manifolds and general convex symplectic manifolds.

math.SG↗