In mathematics, a Lie algebra is semisimple if it is a direct sum of simple Lie algebras. (A simple Lie algebra is a non-abelian Lie algebra without any non-zero proper ideals.)
Throughout the article, unless otherwise stated, a Lie algebra is a finite-dimensional Lie algebra over a field of characteristic 0. For such a Lie algebra , if nonzero, the following conditions are equivalent:
is semisimple;
the Killing form, κ(x,y) = tr(ad(x)ad(y)), is non-degenerate;
has no non-zero abelian ideals;
has no non-zero solvable ideals;
the radical (maximal solvable ideal) of is zero.
and 25 Related for: Semisimple Lie algebra information
mathematics, a Liealgebra is semisimple if it is a direct sum of simple Liealgebras. (A simple Liealgebra is a non-abelian Liealgebra without any non-zero...
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representation is semisimple. Every reductive Liealgebra is isomorphic to the product of an abelian Liealgebra and a semisimpleLiealgebra. For example...
representation theory of semisimpleLiealgebras is one of the crowning achievements of the theory of Lie groups and Liealgebras. The theory was worked...
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split real form of a complex Liealgebra, and because split semisimpleLiealgebras (more generally, split reductive Liealgebras) over any field share many...
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Dynkin diagrams, as in the theory of compact Lie groups or complex semisimpleLiealgebras. Reductive groups over an arbitrary field are harder to classify...
simple Liealgebras Classical Liealgebras: Exceptional Liealgebras: semisimple 1. A semisimpleLie group 2. A semisimpleLiealgebra is a nonzero Lie algebra...
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of the Liealgebra of K is semisimple. Conversely, every complex semisimpleLiealgebra has a compact real form isomorphic to the Liealgebra of a compact...