MathVideos.org
  • Seminars
    • Algebra
      • Associative Rings
        • Ariki-Koike Algebras
        • Cluster Algebras
        • Group Rings
        • Hecke Algebras
        • KLR Algebras
        • Schur Algebras
      • Commutative Algebra
      • Fusion Systems
      • Group Theory
        • Abelian Groups
        • Algebraic Groups
        • Combinatorial Group Theory
        • Computational Group Theory
        • Finite Groups
        • Geometric Group Theory
        • Infinite Groups
        • Lie Groups
        • Permutation Groups
      • Lie Theory
        • Algebraic Groups
        • Lie Algebras
        • Lie Groups
        • p-Adic Groups
        • Representations of Algebraic Groups
      • Non-Associative Algebras
        • Jordan and Axial Algebras
        • Lie Algebras
        • Other Non-Associative Rings
      • Representation Theory
        • Geometric Representation Theory
        • Representations of Algebraic Groups
        • Representations of Finite Groups
        • Representations of Lie Algebras
        • Representations of Symmetric Groups
      • Semigroups
    • Analysis
      • Complex Analysis
      • Functional Analysis
      • Harmonic Analysis
    • Category Theory
      • Derived Categories
      • Higher Category Theory
      • Triangulated Categories
    • Combinatorics
      • Additive Combinatorics
      • Algebraic Combinatorics
      • Extremal Combinatorics
      • Graph Theory
    • Geometry
      • Algebraic Geometry
        • Birational Geometry
      • Differential Geometry
      • Discrete Geometry
      • Non-Commutative Geometry
      • Symplectic Geometry
    • Logic
    • Mathematical Finance
    • Mathematical Physics
    • Number Theory
      • Additive Number Theory
      • Analytic Number Theory
      • Algebraic Number Theory
      • Computational Number Theory
      • Diophantine Equations
      • Diophantine Geometry
      • Number Theory and Forms
      • Probabilistic Number Theory
    • Optimization
    • Probability Theory
    • Topology
      • Algebraic Topology
      • Analytic Topology
      • Differential Topology
      • Dynamical Systems
      • Geometric Topology
  • Short Courses
    • Algebra
    • Analysis
    • Category Theory
    • Combinatorics
    • Geometry
    • Mathematical Physics
    • Number Theory
    • Probability Theory
    • Topology
  • Lecture Courses
    • Algebra
    • Analysis
    • Category Theory
    • Combinatorics
    • Geometry
    • Mathematical Physics
    • Number Theory
    • Probability Theory
    • Topology
  • ···
    MathVideos.org
    • Seminars
      • Algebra
        • Associative Rings
          • Ariki-Koike Algebras
          • Cluster Algebras
          • Group Rings
          • Hecke Algebras
          • KLR Algebras
          • Schur Algebras
        • Commutative Algebra
        • Fusion Systems
        • Group Theory
          • Abelian Groups
          • Algebraic Groups
          • Combinatorial Group Theory
          • Computational Group Theory
          • Finite Groups
          • Geometric Group Theory
          • Infinite Groups
          • Lie Groups
          • Permutation Groups
        • Lie Theory
          • Algebraic Groups
          • Lie Algebras
          • Lie Groups
          • p-Adic Groups
          • Representations of Algebraic Groups
        • Non-Associative Algebras
          • Jordan and Axial Algebras
          • Lie Algebras
          • Other Non-Associative Rings
        • Representation Theory
          • Geometric Representation Theory
          • Representations of Algebraic Groups
          • Representations of Finite Groups
          • Representations of Lie Algebras
          • Representations of Symmetric Groups
        • Semigroups
      • Analysis
        • Complex Analysis
        • Functional Analysis
        • Harmonic Analysis
      • Category Theory
        • Derived Categories
        • Higher Category Theory
        • Triangulated Categories
      • Combinatorics
        • Additive Combinatorics
        • Algebraic Combinatorics
        • Extremal Combinatorics
        • Graph Theory
      • Geometry
        • Algebraic Geometry
          • Birational Geometry
        • Differential Geometry
        • Discrete Geometry
        • Non-Commutative Geometry
        • Symplectic Geometry
      • Logic
      • Mathematical Finance
      • Mathematical Physics
      • Number Theory
        • Additive Number Theory
        • Analytic Number Theory
        • Algebraic Number Theory
        • Computational Number Theory
        • Diophantine Equations
        • Diophantine Geometry
        • Number Theory and Forms
        • Probabilistic Number Theory
      • Optimization
      • Probability Theory
      • Topology
        • Algebraic Topology
        • Analytic Topology
        • Differential Topology
        • Dynamical Systems
        • Geometric Topology
    • Short Courses
      • Algebra
      • Analysis
      • Category Theory
      • Combinatorics
      • Geometry
      • Mathematical Physics
      • Number Theory
      • Probability Theory
      • Topology
    • Lecture Courses
      • Algebra
      • Analysis
      • Category Theory
      • Combinatorics
      • Geometry
      • Mathematical Physics
      • Number Theory
      • Probability Theory
      • Topology
    • ···
      MathVideos.org
      • Seminars
        • Algebra
          • Associative Rings
            • Ariki-Koike Algebras
            • Cluster Algebras
            • Group Rings
            • Hecke Algebras
            • KLR Algebras
            • Schur Algebras
          • Commutative Algebra
          • Fusion Systems
          • Group Theory
            • Abelian Groups
            • Algebraic Groups
            • Combinatorial Group Theory
            • Computational Group Theory
            • Finite Groups
            • Geometric Group Theory
            • Infinite Groups
            • Lie Groups
            • Permutation Groups
          • Lie Theory
            • Algebraic Groups
            • Lie Algebras
            • Lie Groups
            • p-Adic Groups
            • Representations of Algebraic Groups
          • Non-Associative Algebras
            • Jordan and Axial Algebras
            • Lie Algebras
            • Other Non-Associative Rings
          • Representation Theory
            • Geometric Representation Theory
            • Representations of Algebraic Groups
            • Representations of Finite Groups
            • Representations of Lie Algebras
            • Representations of Symmetric Groups
          • Semigroups
        • Analysis
          • Complex Analysis
          • Functional Analysis
          • Harmonic Analysis
        • Category Theory
          • Derived Categories
          • Higher Category Theory
          • Triangulated Categories
        • Combinatorics
          • Additive Combinatorics
          • Algebraic Combinatorics
          • Extremal Combinatorics
          • Graph Theory
        • Geometry
          • Algebraic Geometry
            • Birational Geometry
          • Differential Geometry
          • Discrete Geometry
          • Non-Commutative Geometry
          • Symplectic Geometry
        • Logic
        • Mathematical Finance
        • Mathematical Physics
        • Number Theory
          • Additive Number Theory
          • Analytic Number Theory
          • Algebraic Number Theory
          • Computational Number Theory
          • Diophantine Equations
          • Diophantine Geometry
          • Number Theory and Forms
          • Probabilistic Number Theory
        • Optimization
        • Probability Theory
        • Topology
          • Algebraic Topology
          • Analytic Topology
          • Differential Topology
          • Dynamical Systems
          • Geometric Topology
      • Short Courses
        • Algebra
        • Analysis
        • Category Theory
        • Combinatorics
        • Geometry
        • Mathematical Physics
        • Number Theory
        • Probability Theory
        • Topology
      • Lecture Courses
        • Algebra
        • Analysis
        • Category Theory
        • Combinatorics
        • Geometry
        • Mathematical Physics
        • Number Theory
        • Probability Theory
        • Topology

      Alexander Gamburd: Expander Graphs, Thin Groups, and Super-strong Approximation

      6th February, 2012

      These videos are part of the MSRI workshop Hot Topics: Thin Groups and Super-strong Approximation, which took place in February of 2012.

      1. Lecture 1
      2. Lecture 2
      Additive combinatorics Algebra Combinatorics Expanders Graph theory Group theory Lie groups Strong approximation

      You may also like

      Alan Logan: Free groups via graphs

      5th November, 2020

      Michel Brion: The isogeny category of commutative algebraic groups

      10th August, 2016

      Eduardo Oregón-Reyes: Cubulated groups and virtual specialness

      21st June, 2021

      Asilata Bapat: Triangulations, rigid motions, and applications to representation theory

      27th June, 2022

      Andrei Okounkov: Weyl groups and their generalizations in enumerative geometry

      15th March, 2016

      Charlotte Chan: Deligne-Lusztig theory: examples and applications

      20th May, 2024

      In ‘Short Courses’

      • All Short Courses
      • Algebra
      • Analysis
      • Category Theory
      • Combinatorics
      • Geometry
      • Mathematical Physics
      • Number Theory
      • Probability Theory
      • Topology

      About MathVideos

      MathVideos attempts to produce a catalogue of all research-level seminar and course videos from across the Internet. Started by David Craven, it is not affiliated in any way with the University of Birmingham.

      Privacy Policy

      Contact Us

      Most recent videos

      • Nikolay Bogachev: Geometry, Arithmetic, and Dynamics of Discrete Groups, XXI 3rd December, 2024
      • David Fernández: Non-commutative Poisson geometry and pre-Calabi-Yau algebras 2nd December, 2024
      • Hadi Salmasian: Lie Groups and Quantization, XXIII 2nd December, 2024
      • Jon Woolf: Heart fans as universal phase diagrams 28th November, 2024
      • Nikolay Bogachev: Geometry, Arithmetic, and Dynamics of Discrete Groups, XX 28th November, 2024