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Actividades organizadas por ICMAT



Seminario Thematic program "Orthogonal polynomials and Special functions in approximation theory and mathematical physics"

Título: Asymptotics and numerics of large degree Gauss quadrature in the Santander--Alkmaar project.
Ponente: Nico Temme (IAA, Alkmaar & CWI, Amsterdam).
Fecha y hora: Martes 17 octubre. 12:00.
Lugar: Aula Gris I ICMAT.
Abstract: Our interest in this topic arose after the publication of a paper by Bogaert, where the Legendre case was considered, which is the simplest example of Gauss quadrature for the classical  orthogonal polynomials. In this lecture we consider the Hermite, Laguerre and Jacobi polynomials. We show how to use known and new asymptotic expansions of the polynomials to obtain expansions of their zeros. For zeros close to turning points, or other critical points,  we need extra expansions of the coefficients in the expansions of the polynomials and the zeros. We show which special forms of the weights we use in order to control the numerical accuracy.

Seminario Teoría de grupos

Título: p-GROUPS AND COHOMOLOGY
Ponente: Jon González,  UPV-EHU
Fecha y hora:  Wednesday, 18 October - 11:30
Lugar:  Aula 520, Módulo 17, Departamento de Matemáticas, UAM (Campus de Cantoblanco, Madrid)
Abstract: Let G be a d-generated finite p-groups of nilpotency class c. In this talk we will prove that the number of possible isomorphism types for the mod p-cohomology algebra of G is bounded by a function f depending on p, d and c. This is a joint work with Oihana Garaialde Ocaña.

Colloquium UAM-ICMAT

Título: PDE in Lie groups
Ponente: Giovanna Citti,  U. Bolonia
Fecha y hora:  Friday, 20 October - 12:00
Lugar:  Aula 520, Módulo 17, Departamento de Matemáticas, UAM (Campus de Cantoblanco, Madrid).
Abstract: The motivation of the problem comes from a problem of visual perception. Indeed the visual cortex has been modelled as a Lie group, with a totally degenerate metric, also called subriemannian.
The associated PDE can be expressed as a sum of squares of vector fields, and the study of these type of equations under suitable geometric condition, has been started by Hormander and Rothschild – Stein. However regularity at the boundary, well known in the Euclidean setting, was still open even for the subriemannian Laplacian. We will face the problem with a suitable extension of a result of Caffarelli and Silvestre to this degenerate setting.

Seminario Thematic program "Orthogonal polynomials and Special functions in approximation theory and mathematical physics"

Título: Hermite multipliers on Modulation spaces
Ponente: Sundaram Thangavelu (Indian Institute of Science, Bangalore)
Fecha y hora: viernes 20 octubre. 12:00.
Lugar: Sala Gris II ICMAT.
Abstract: In this talk which is based on my joint work with Divyang Bhimani and Rakesh Balhara, we consider multipliers associated to the Hermite operator H = - Δ + |x|2 on modulation spaces Mp,q (ℝd). We prove that the operator m(H) is bounded on Mp,q (ℝd) under standard conditions on m, for suitable choice of p and q. As an application, we point out that the solutions to the free wave and Schrödinger equations associated to H with initial data in a modultion space will remain in the same modulation space for all times.