Theory of multi-fans
| dc.creator | Hattori, Akio | |
| dc.creator | Masuda, Mikiya | |
| dc.date | 2001-06-27 | |
| dc.date | 2003-12-10 | |
| dc.date.accessioned | 2026-07-07T04:42:20Z | |
| dc.date.available | 2026-07-07T04:42:20Z | |
| dc.description | We introduce the notion of a multi-fan. It is a generalization of that of a fan in the theory of toric variety in algebraic geometry. Roughly speaking a toric variety is an algebraic variety with an action of algebraic torus of the same dimension as that of the variety, and a fan is a combinatorial object associated with the toric variety. Algebro-geometric properties of the toric variety can be described in terms of the associated fan. We develop a combinatorial theory of multi-fans and define ``topological invariants'' of a multi-fan. A smooth manifold with an action of a compact torus of half the dimension of the manifold and with some orientation data is called a torus manifold. We associate a multi-fan with a torus manifold, and apply the combinatorial theory to describe topological invariants of the torus manifold. A similar theory is also given for torus orbifolds. As a related subject a generalization of the Ehrhart polynomial concerning the number of lattice points in a convex polytope is discussed. | |
| dc.identifier | https://arxiv.org/abs/math/0106229 | |
| dc.identifier | http://arxiv.org/abs/math/0106229 | |
| dc.identifier | Osaka J. Math. 40 (2003), 1-68 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/61737 | |
| dc.subject | Symplectic Geometry | |
| dc.subject | Algebraic Topology | |
| dc.title | Theory of multi-fans | |
| dc.type | text |