Representation theory: Introduction
This lecture is an introduction to representation theory of finite groups. We define linear and permutation representations, and give some examples for the icosahedral group. We then discuss the problem of writing a representation as a sum of smaller ones, which leads to the concept of irr
From playlist Representation theory
RT1: Representation Theory Basics
Representation Theory: We present basic concepts about the representation theory of finite groups. Representations are defined, as are notions of invariant subspace, irreducibility and full reducibility. For a general finite group G, we suggest an analogue to the finite abelian case, whe
From playlist *** The Good Stuff ***
RT6. Representations on Function Spaces
Representation Theory: We note how to transfer a group action of a group G on a set X to a group action on F(X), the functions on X. Because F(X) is a vector space, we obtain a representation of the group, and we can apply previous techniques. In particular, the group acts on itself in
From playlist Representation Theory
Visual Group Theory, Lecture 1.6: The formal definition of a group
Visual Group Theory, Lecture 1.6: The formal definition of a group At last, after five lectures of building up our intuition of groups and numerous examples, we are ready to present the formal definition of a group. We conclude by proving several basic properties that are not built into t
From playlist Visual Group Theory
Abstract Algebra 1.5 : Examples of Groups
In this video, I introduce many important examples of groups. This includes the group of (rigid) motions, orthogonal group, special orthogonal group, the dihedral groups, and the "finite cyclic group" Z/nZ (or Z_n). Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animatio
From playlist Abstract Algebra
Representation theory: Abelian groups
This lecture discusses the complex representations of finite abelian groups. We show that any group is iomorphic to its dual (the group of 1-dimensional representations, and isomorphic to its double dual in a canonical way (Pontryagin duality). We check the orthogonality relations for the
From playlist Representation theory
Abstract Algebra | The dihedral group
We present the group of symmetries of a regular n-gon, that is the dihedral group D_n. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/
From playlist Abstract Algebra
Representation theory: Frobenius groups
We recall the definition of a Frobenius group as a transitive permutation group such that any element fixing two points is the identity. Then we prove Frobenius's theorem that the identity together with the elements fixing no points is a normal subgroup. The proof uses induced representati
From playlist Representation theory
Symmetric Groups (Abstract Algebra)
Symmetric groups are some of the most essential types of finite groups. A symmetric group is the group of permutations on a set. The group of permutations on a set of n-elements is denoted S_n. Symmetric groups capture the history of abstract algebra, provide a wide range of examples in
From playlist Abstract Algebra
From PSL2 representation rigidity to profinite rigidity - Alan Reid and Ben McReynolds
Arithmetic Groups Topic: From PSL2 representation rigidity to profinite rigidity Speakers: Alan Reid and Ben McReynolds Affiliations: Rice University; Purdue University Date: February 9, 2022 In the first part of this talk, we take the ideas of the second talk and focus on the case of (a
From playlist Mathematics
Profinite Completions and Representation Rigidity - Ryan Spitler
Arithmetic Groups Topic: Profinite Completions and Representation Rigidity Speaker: Ryan Spitler Affiliation: Rice University Date: February 02, 2022 Taking up the terminology established in the first lecture, in 1970 Grothendieck showed that when two groups (G,H) form a Grothendieck pai
From playlist Mathematics
Profinite rigidity – Alan Reid – ICM2018
Topology Invited Lecture 6.7 Profinite rigidity Alan Reid Abstract: We survey recent work on profinite rigidity of residually finite groups. © International Congress of Mathematicians – ICM www.icm2018.org Os direitos sobre todo o material deste canal pertencem ao Instituto de Mat
From playlist Topology
Rolando de Santiago: "L2 cohomology and maximal rigid subalgebras of s-malleable deformations"
Actions of Tensor Categories on C*-algebras 2021 "L2 cohomology and maximal rigid subalgebras of s-malleable deformations" Rolando de Santiago - Purdue University, Department of Mathematics Abstract: A major theme in the study of von Neumann algebras is to investigate which structural as
From playlist Actions of Tensor Categories on C*-algebras 2021
Boris Apanasov: Non-rigidity for Hyperbolic Lattices and Geometric Analysis
Boris Apanasov, University of Oklahoma Title: Non-rigidity for Hyperbolic Lattices and Geometric Analysis We create a conformal analogue of the M. Gromov-I. Piatetski-Shapiro interbreeding construction to obtain non-faithful representations of uniform hyperbolic 3-lattices with arbitrarily
From playlist 39th Annual Geometric Topology Workshop (Online), June 6-8, 2022
On the long-term dynamics of nonlinear dispersive evolution equations - Wilhelm Schlag
Analysis Seminar Topic: On the long-term dynamics of nonlinear dispersive evolution equations Speaker: Wilhelm Schlag Affiliation: University of Chicago Visiting Professor, School of Mathematics Date: Febuary 14, 2018 For more videos, please visit http://video.ias.edu
From playlist Mathematics
Grothendieck Pairs and Profinite Rigidity - Martin Bridson
Arithmetic Groups Topic: Grothendieck Pairs and Profinite Rigidity Speaker: Martin Bridson Affiliation: Oxford University Date: January 26, 2022 If a monomorphism of abstract groups H↪G induces an isomorphism of profinite completions, then (G,H) is called a Grothendieck pair, recalling t
From playlist Mathematics
Rigidity for von Neumann algebras – Adrian Ioana – ICM2018
Analysis and Operator Algebras Invited Lecture 8.5 Rigidity for von Neumann algebras Adrian Ioana Abstract: We survey some of the progress made recently in the classification of von Neumann algebras arising from countable groups and their measure preserving actions on probability spaces.
From playlist Analysis & Operator Algebras
Cyril Houdayer: Noncommutative ergodic theory of lattices in higher rank simple algebraic groups
Talk by Cyril Houdayer in the Global Noncommutative Geometry Seminar (Americas) on March 18, 2022. https://globalncgseminar.org/talks/tba-28/
From playlist Global Noncommutative Geometry Seminar (Americas)
Rigid Analytic Vector in Locally Analytic Representations by Aranya Lahari
PERFECTOID SPACES ORGANIZERS: Debargha Banerjee, Denis Benois, Chitrabhanu Chaudhuri, and Narasimha Kumar Cheraku DATE & TIME: 09 September 2019 to 20 September 2019 VENUE: Madhava Lecture Hall, ICTS, Bangalore Scientific committee: Jacques Tilouine (University of Paris, France) Eknath
From playlist Perfectoid Spaces 2019
Representations of Finite Groups | Definitions and simple examples.
We define the notion of a representation of a group on a finite dimensional complex vector space. We also explore one and two dimensional representations of the cyclic group Zn. Please Subscribe: https://www.youtube.com/michaelpennmath?sub_confirmation=1 Personal Website: http://www.mich
From playlist Representations of Finite Groups