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arXiv · 2503.18750

Contact quasi-states and their applications

Abstract

We introduce the notions of partial contact quasi-state and contact quasi-measure. Using the contact spectral invariant from the work by Djordjević-Uljarević-Zhang, one can construct partial contact quasi-states and contact quasi-measures on each contact manifold fillable by a Liouville domain with non-vanishing and $\mathbb{Z}$-graded symplectic homology. As an application, we present an alternative proof of the contact big fibre theorem from the recent work by Sun-Uljarević-Varolgunes under a mild topological condition. Our proof follows a more "classical" approach developed by Entov-Polterovich in the symplectic setting.

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Igor Uljarević, Jun Zhang. 2025-03-24. Contact quasi-states and their applications. https://arxiv.org/abs/2503.18750

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