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Seminars

Geometry Seminar [July 24, 2015]

2015.07.19 Sun up

Geometry Seminar

Speaker: Gaël Meigniez (Université de Bretagne-Sud)
Title: h-principles and foliations
Date: 16:30-18:00, Friday 24 July
Place: Biwako-Kusatsu Campus, West-Wing 7th Floor, the 1st Laboratory of Mathematics
Abstract:(collaboration with Francois Laudenbach)
Gromov’s h-principle is a collection of powerful tools to build geometric objects, by deformation of a formal data whose existence is easy to decide. This talk will introduce a new approach to the h-principle, in two steps. From the formal data, the first step builds a Haefliger Gamma-structure (singular foliation) of codimension zero with the desired transverse geometry. This step works, for several interesting geometries, on all manifolds, even closed (I shall treat the example of contact geometry). The second step regularizes the Gamma-structure; it consists essentially in a simple adaptation of Thurston’s inflation method; it works for all geometries, but only on open manifolds. We use a special subdivision of the simplex, due to Thom.

Geometry Seminar [July 17, 2015]

2015.07.04 Sat up

July 17, 2015 @BKC campus, West Wing 7th floor 3rd lab., 16：30–18:00

Yuji Hirota（Azabu University）
Title: A brief look at Poisson geometry
Abstract: The talk is an overview of Poisson geometry. We plan to deal with Poisson manifolds involving Lie groupoids/algebroids at the first half of the talk, and at the second half, will discuss Dirac structures which are useful frameworks to unify Poisson geometry and symplectic geometry.