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Title: An elementary alternative to ECH capacities
The embedded contact homology (ECH) capacities are a sequence of numerical invariants of symplectic four-manifolds that give (sometimes sharp) obstructions to symplectic embeddings. These capacities are defined using embedded contact homology, and establishing their basic properties currently requires Seiberg–Witten theory. In this paper we define a sequence of symplectic capacities in four dimensions using only basic notions of holomorphic curves. The capacities satisfy the same basic properties as ECH capacities and agree with the ECH capacities for the main examples for which the latter have been computed, namely convex and concave toric domains. The capacities are also useful for obstructing symplectic embeddings into closed symplectic four-manifolds. This work is inspired by a recent preprint of McDuff and Siegel [D. McDuff, K. Siegel, arXiv [Preprint] (2021)], giving a similar elementary alternative to symplectic capacities from rational symplectic field theory (SFT).  more » « less
Award ID(s):
2005437
PAR ID:
10389159
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
119
Issue:
35
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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