arXiv subjects

Danijel Djordjević

Publications and source records attributed to Danijel Djordjević.

2 recordsLinked to original sources

arXiv2025

Quantitative contact Hamiltonian dynamics

This paper presents a systematic quantitative study of contact rigidity phenomena based on the contact Hamiltonian Floer theory established by Merry-Uljarević. Our quantitative approach applies to arbitrary admissible contact Hamiltonian functions on the contact boundary $M = \partial W$ of a ${\rm weakly}^{+}$-monotone symplectic manifold $W$. From a theoretical standpoint, we develop a comprehensive contact spectral invariant theory. As applications, the properties of these invariants enable us to establish several fundamental results: the contact big fiber theorem, sufficient conditions for orderability, and the existence results of translated points. Furthermore, we uncover a non-traditional filtration structure on contact Hamiltonian Floer groups, which we formalize through the introduction of a novel type of persistence modules, called gapped modules, that are only parametrized by a partially ordered set. Among the various properties of contact spectral invariants, we highlight that the triangle inequality is derived through an innovative analysis of a pair-of-pants construction in the contact-geometric framework.

math.SG↗

arXiv2023

Quantitative characterization in contact Hamiltonian dynamics -- I

Based on the contact Hamiltonian Floer theory established by Will J. Merry and the second author that applies to any admissible contact Hamiltonian system $(M, ξ= \ker α, h)$, where $h$ is a contact Hamiltonian function on a Liouville fillable contact manifold $(M, ξ= \ker α)$, we associate a persistence module to $(M, ξ, h)$, called a gapped module, that is parametrized only by a partially ordered set. It enables us to define various numerical Floer-theoretic invariants. In this paper, we focus on the contact spectral invariants and their applications. Several key properties are proved, which include stability with respect to the Shelukhin-Hofer norm in contact geometry and a triangle inequality of contact spectral invariants. In particular, our stability property does not involve any conformal factors; our triangle inequality is derived from a novel analysis on pair-of-pants in the contact Hamiltonian Floer homology. While this paper was nearing completion, the authors were made aware of upcoming work by Dylan Cant, where a similar persistence module for contact Hamiltonian dynamics was constructed.

math.SG↗