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arXiv · 2310.11993

Contact non-squeezing at large scale via generating functions

Abstract

Using SFT techniques, Eliashberg, Kim and Polterovich (2006) proved that if $πR_2^2 \leq K \leq πR_1^2$ for some integer $K$ then there is no contact squeezing in $\mathbb{R}^{2n} \times S^1$ of the prequantization of the ball of radius $R_1$ into the prequantization of the ball of radius $R_2$. This result was extended to the case of balls of radius $R_1$ and $R_2$ with $1 \leq πR_2^2 \leq πR_1^2$ by Chiu (2017) and the first author (2016), using respectively microlocal sheaves and SFT. In the present article we recover this general contact non-squeezing theorem using generating functions, a classical method based on finite dimensional Morse theory. More precisely, we develop an equivariant version, with respect to a certain action of a finite cyclic group, of the generating function homology for domains of $\mathbb{R}^{2n} \times S^1$ defined by the second author (2011). A key role in the construction is played by translated chains of contactomorphisms, a generalization of translated points.

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BibTeXRIS

Maia Fraser, Sheila Sandon, Bingyu Zhang. 2025-04-15. Contact non-squeezing at large scale via generating functions. https://arxiv.org/abs/2310.11993

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