## Geometry & Topology

### The topology of toric symplectic manifolds

Dusa McDuff

#### Abstract

This is a collection of results on the topology of toric symplectic manifolds. Using an idea of Borisov, we show that a closed symplectic manifold supports at most a finite number of toric structures. Further, the product of two projective spaces of complex dimension at least two (and with a standard product symplectic form) has a unique toric structure. We then discuss various constructions, using wedging to build a monotone toric symplectic manifold whose center is not the unique point displaceable by probes, and bundles and blow ups to form manifolds with more than one toric structure. The bundle construction uses the McDuff–Tolman concept of mass linear function. Using Timorin’s description of the cohomology algebra via the volume function we develop a cohomological criterion for a function to be mass linear, and explain its relation to Shelukhin’s higher codimension barycenters.

#### Article information

Source
Geom. Topol., Volume 15, Number 1 (2011), 145-190.

Dates
Received: 9 June 2010
Revised: 29 September 2010
Accepted: 15 November 2010
First available in Project Euclid: 20 December 2017

Permanent link to this document
https://projecteuclid.org/euclid.gt/1513732274

Digital Object Identifier
doi:10.2140/gt.2011.15.145

Mathematical Reviews number (MathSciNet)
MR2776842

Zentralblatt MATH identifier
1218.14045

#### Citation

McDuff, Dusa. The topology of toric symplectic manifolds. Geom. Topol. 15 (2011), no. 1, 145--190. doi:10.2140/gt.2011.15.145. https://projecteuclid.org/euclid.gt/1513732274

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