## Algebraic & Geometric Topology

### Hofer–Zehnder capacity and Bruhat graph

Alexander Caviedes Castro

#### Abstract

We find bounds for the Hofer–Zehnder capacity of spherically monotone coadjoint orbits of compact Lie groups with respect to the Kostant–Kirillov–Souriau symplectic form in terms of the combinatorics of their Bruhat graphs. We show that our bounds are sharp for coadjoint orbits of the unitary group and equal in that case to the diameter of a weighted Cayley graph.

#### Article information

Source
Algebr. Geom. Topol., Volume 20, Number 2 (2020), 565-600.

Dates
Revised: 4 December 2018
Accepted: 19 April 2019
First available in Project Euclid: 30 April 2020

https://projecteuclid.org/euclid.agt/1588212070

Digital Object Identifier
doi:10.2140/agt.2020.20.565

Mathematical Reviews number (MathSciNet)
MR4092307

Zentralblatt MATH identifier
07195372

#### Citation

Caviedes Castro, Alexander. Hofer–Zehnder capacity and Bruhat graph. Algebr. Geom. Topol. 20 (2020), no. 2, 565--600. doi:10.2140/agt.2020.20.565. https://projecteuclid.org/euclid.agt/1588212070

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