Representation theory of finite groups

Representation theory is about understanding and exploiting symmetry using linear algebra. The central objects of study are linear actions of groups on vector spaces. This gives rise to a very structured and beautiful theory. The aim of this course dealing with finite groups and complex vector spaces is to introduce this theory.

Representation theory plays a major role in mathematics and physics. For example, it provides a framework for understanding finite groups, special functions, and Lie groups and algebras. In number theory, Galois groups are studied via their representations; this is closely related to modular forms. In physics, representation theory is the mathematical basis for the theory of elementary particles.

After introducing the concept of a representation of a group, we will study decompositions of representations into irreducible constituents. A finite group only has finitely many distinct irreducible representations; these are encoded in a matrix called the character table of the group. One of the goals of this course is to use representation theory to prove Burnside's theorem on solvability of groups whose order is divisible by at most two prime numbers. Another goal is to construct all irreducible representations of the symmetric group.

References

• We will follow the book Representation Theory of Finite Groups by Benjamin Steinberg.
• Another reference is Representation Theory: A First Course by William Fulton and Joe Harris.

Date and time info
Thursdays 7:30-9:00 and Fridays 9:15-10:45

Keywords
Representation theory, Group actions, Characters

Prerequisites
Basic knowledge about groups and vector spaces