Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Schur Lemmas

Description

This lecture covers topics such as Burnside's Lemma, Schur Lemmas, and their proofs. The slides discuss group theory, quantum mechanics, and group representations, presenting mathematical concepts and proofs related to these topics.

Official source

Related concepts (27)

Group representation

In the mathematical field of representation theory, group representations describe abstract groups in terms of bijective linear transformations of a vector space to itself (i.e. vector space automorphisms); in particular, they can be used to represent group elements as invertible matrices so that the group operation can be represented by matrix multiplication. In chemistry, a group representation can relate mathematical group elements to symmetric rotations and reflections of molecules.

Lemma (mathematics)

In mathematics, informal logic and argument mapping, a lemma (: lemmas or lemmata) is a generally minor, proven proposition which is used as a stepping stone to a larger result. For that reason, it is also known as a "helping theorem" or an "auxiliary theorem". In many cases, a lemma derives its importance from the theorem it aims to prove; however, a lemma can also turn out to be more important than originally thought. From the Ancient Greek λῆμμα, (perfect passive εἴλημμαι) something received or taken.

Mathematical proof

A mathematical proof is a deductive argument for a mathematical statement, showing that the stated assumptions logically guarantee the conclusion. The argument may use other previously established statements, such as theorems; but every proof can, in principle, be constructed using only certain basic or original assumptions known as axioms, along with the accepted rules of inference. Proofs are examples of exhaustive deductive reasoning which establish logical certainty, to be distinguished from empirical arguments or non-exhaustive inductive reasoning which establish "reasonable expectation".

Mathematical induction

Mathematical induction is a method for proving that a statement is true for every natural number , that is, that the infinitely many cases all hold. Informal metaphors help to explain this technique, such as falling dominoes or climbing a ladder: Mathematical induction proves that we can climb as high as we like on a ladder, by proving that we can climb onto the bottom rung (the basis) and that from each rung we can climb up to the next one (the step). A proof by induction consists of two cases.

Group theory

In abstract algebra, group theory studies the algebraic structures known as groups. The concept of a group is central to abstract algebra: other well-known algebraic structures, such as rings, fields, and vector spaces, can all be seen as groups endowed with additional operations and axioms. Groups recur throughout mathematics, and the methods of group theory have influenced many parts of algebra. Linear algebraic groups and Lie groups are two branches of group theory that have experienced advances and have become subject areas in their own right.

Related lectures (57)

Orthogonality and Characters

Explores orthogonality, irreducible representations, and symmetry properties in physics and group theory.

Group Theory & Quantum Mechanics

Explores k-fold degenerate sets of eigenfunctions and their basis for irreducible representations.

Schur Lemmas: Symmetry Reduction in Quantum Mechanics

Delves into symmetry reduction in quantum mechanics using Schur Lemmas, showcasing how group representations simplify system analysis.

The Schur Lemma: Physical Interpretation

Explores the physical interpretation of the Schur lemma in quantum physics.

Vector Operators: Rotation and Quantum Mechanics