The Chevalley-Serre relations, sometimes called simply the "Serre relations," present a finite-dimensional semisimple Lie
algebra over the complex numbers for each Cartan matrix. That is, if is a
Cartan matrix then,
up to isomorphism, there exists a unique
finite-dimensional semisimple Lie algebra
over the complex numbers (whose Cartan
matrix is equivalent to
) such that
is defined by a set of
generators
subject to the following Chevalley-Serre
relations:
1.
2.
and
if
3.
4.
5.
if
6.
if
.
Moreover,
has rank
and the
's
generate a Cartan subalgebra. For proof, see
Serre (1987).