Departamento de Matemáticas UAM

  • Inicio
  • Inicio (2)
  • Presentación
  • Directorio
  • Organigrama
  • Intranet
  • Convocatoria de plazas

Investigación

  • Ayudas para investigación
  • Departamento
  • Grupos de investigación
  • Institutos de investigación
  • Seminarios
  • Joint Mathematics Colloquium ICMAT-UAM-UC3M-UCM
    • Coloquios 2022/2023
    • Coloquios 2021/2022
    • Coloquio UAM-ICMAT
      • Coloquios 2019/2020
      • Coloquios 2018/2019
      • Coloquios 2017/2018
      • Coloquios 2016/2017
      • Coloquios 2015/2016
      • Coloquios 2014/2015
      • Coloquios 2013/2014
      • Coloquios 2012/2013
      • Coloquios 2011/2012
      • Coloquios 2010/2011
      • Coloquios 2009/2010
  • Memorial Rubio de Francia
  • Coloquio Premio Rubio de Francia
  • Coloquios Departamento

Quantum expanders and applications

Gilles Pisier, Texas A&M University (cartel)

Viernes 22 de mayo, Módulo 17, aula 520, 12:00h.

Abstract.- 

\[\]
We will explain the notion of quantum expander, a sort of non-commutative analogue of expanding families of graphs, where an n-regular finite graph with N vertices admitting a spectral gap
\[\varepsilon>0\]
is replaced by an
n-tuple of unitary matrices of size N
\[\times\]
N with an analogous spectral gap
\[\varepsilon>0\]
. Here
n,
\[\varepsilon\]
should remain fixed while
N
\[\to\infty\]
. The talk will relate such questions with the non-separability of the set of finite dimensional (actually even of 3-dimensional) operator spaces which goes back to joint work with Marius Junge, and several more recent "quantitative" refinements obtained using an estimate of the metric entropy of the set of quantum expanders. We will show how the presence of a quantum expander restricts the number of distinct irreducible representations, in analogy with a well known question of Wigderson for expanders.

Volver

CSS Valid | XHTML Valid | Top | + | - | reset
Copyright © Eximium 2025 All rights reserved. Custom Design by Youjoomla.com
Inicio