Part 3:    • What is Lie theory? Here is the big p...  

Around 11:50, can't imagine that this error got in it should have been SU(n) = {U in U(n), det U = 1}.

Orthogonal and unitary groups. Rotational symmetries, real and complex, are particularly useful in the field of Lie theory, because their (complexified) Lie algebras, together with that of the symplectic group Sp(n), are the only infinite families of simple Lie algebras. This video is to familiarise with the SO(n), SU(n) notations, and provides further motivation to study Lie theory.

Files for download:
Go to https://www.mathemaniac.co.uk/download and enter the following password: orthogonalunitary

Video chapters:
00:00 Introduction
01:04 Real rotation in n dimensions
07:03 Complex rotation

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