nLab
classical Lie group

Idea

The classification of simple Lie groups contains four infinite series of “classical” simple Lie groups:

• $A_n = SU(n+1)$, the special unitary group

• $B_n = SO(2n+1)$, the special orthogonal group

• $C_n = Sp(n)$, the symplectic group

• $D_n = SO(2n)$, the special orthogonal group

Apart from this there are five exceptional Lie groups.

graphics grabbed from Schwichtenberg

More generally, other matrix Lie groups, such as the general linear group $GL(n)$, may be called “classical”.

Related concepts

• exceptional isomorphism