## terça-feira, 2 de agosto de 2011

### Eventos da semana

Geometric construction of characteristic classes

Palestrante: José Luis Cisneros-Molina (Instituto de Matemáticas de Cuernavaca - UNAM)

Quando: Quarta-feira, 3 de agosto, às 14h
Onde: Auditório Prof. Luiz Antonio Fávaro

Resumo: Abstract: In this talk we present a geometric construction of characteristic classes of vector bundles (Stiefel-Whitney and Chern classes) using generic bundle morphisms. Joint work with Marcelo Aguilar and Eduardo Frías.
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Conferência
Rank gradient in co-final towers of certain Kleinian groups

Palestrante: Darlan Girao (University of Texas)

Quando: Sexta-feira, 5 de agosto, às 14h
Onde: sala 4-001

Resumo: Recently Abert and Nikolov related two important problems: 1. The rank vs. Heegaard genus conjecture for hyperbolic 3-manifolds, which is a long standing question in low dimensional topology; 2. The Fixed Price problem in topological dynamics. Counter examples for this conjecture have just been announced by Tao Li. I will survey along these notions and explain what should be expected from the relationship set by Abert-Nikolov in light of Li's work. I will finally show some of my results and explain
how they fit into this picture.

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Seminário de Geometria e Física Matemática
Simultaneous deformations of Maurer-Cartan elements

Palestrante: Marco Zambon (Instituto de Ciências Matemáticas, Madrid, Espanha)

Quando: Sexta-feira, 5 de agosto, às 15h
Onde: Auditório Prof. Luiz Antonio Fávaro

Resumo: Given an $L_{\infty}$-algebra, we prove a theorem about the simultaneous deformation of the $L_{\infty}$-algebra structure and of its Maurer-Cartan elements. The main tool is Ted Voronov's derived bracket construction. The above theorem allows to make statements about the deformation theory of a wide class of algebraic and geometric objects. We will discuss, among others, the example of deformations of twisted Poisson structures. This is joint work with Yael Fregier (Univ. Lens).
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Informações
Seção de Eventos do ICMC
Tel (16) 3373-9146