 Universal enveloping algebra

The universal enveloping algebra is a fundamental concept in the theory of Lie algebras and representation theory. Given a Lie algebra \(\mathfrak{g}\), its universal enveloping algebra, denoted as \(U(\mathfrak{g})\), is an associative algebra that encodes the structure of the Lie algebra in such a way that representation theory can be applied to it using methods of associative algebras.