Operations on Elements

x + y : AlgLieElt, AlgLieElt -> AlgLieElt
x + y : AlgMatLieElt, AlgMatLieElt -> AlgMatLieElt
x - y : AlgLieElt, AlgLieElt -> AlgLieElt
x - y : AlgMatLieElt, AlgMatLieElt -> AlgMatLieElt
x * y : AlgLieElt, AlgLieElt -> AlgLieElt
x * y : AlgMatLieElt, AlgMatLieElt -> AlgMatLieElt

Contents

IsCentral(L, M) : AlgLie,AlgLieElt -> BoolElt
IsCentral(L, M) : AlgMatLie,AlgMatLieElt -> BoolElt
Given an element x of the Lie algebra L, return true if x is central in L.
NonNilpotentElement(L) : AlgLie -> AlgLieElt
Given a (structure constant) Lie algebra L, this function returns an element of L that is not nilpotent, or the zero element of L if no such element exists.

The algorithm follows [dG00], Para 2.7.

Example AlgLie_NonNilpotentElement (H107E45)

We construct a non-nilpotent element of a Lie algebra.
> L:=LieAlgebra("G2",RationalField());
> NonNilpotentElement(L);
(0 0 0 0 0 1 0 0 0 0 0 0 0 0)
AdjointMatrix(L, x) : AlgLie, AlgLieElt -> AlgMatLieElt
RightAdjointMatrix(L, x) : AlgLie, AlgLieElt -> AlgMatLieElt
Given a (structure constant) Lie algebra L and an element x of a subalgebra or ideal of L, return the matrix of (ad) xas an element of a matrix Lie algebra.

Example AlgLie_Other (H107E46)

> L:=LieAlgebra("B2",RationalField());
> AdjointMatrix(L, L.1);
[ 0  0  0  0  0  0  0  0  0  0]
[ 0  0  0  0  0  0  0  0  0  0]
[ 0  0  0  0  0  0  0  0  0  0]
[ 0  0  0  0  0  0  0  0  0  0]
[ 1  0  0  0  0  0  0  0  0  0]
[ 2  0  0  0  0  0  0  0  0  0]
[ 0  0  0  0  0  0  0  0  0  0]
[ 0 -1  0  0  0  0  0  0  0  0]
[ 0  0  1  0  0  0  0  0  0  0]
[ 0  0  0  0  0 -1  0  0  0  0]

Indexing

a[i] : AlgLieElt, RngIntElt -> RngElt
a[i] : AlgMatLieElt, RngIntElt -> ModTupRngElt
If a is an element of a structure constant Lie algebra L of dimension n and 1 ≤i≤n is a positive integer, then the i-th component of the element a is returned (as an element of the base ring R of L).

If a is an element of a matrix Lie algebra L of degree n and 1 ≤i ≤n then the ith row of the matrix a is returned.

a[i] := r : AlgLieElt, RngIntElt, RngElt -> AlgLieElt
a[i] := r : AlgMatLieElt, RngIntElt, ModTupRngElt -> AlgMatLieElt
Given an element a belonging to a structure constant Lie algebra of dimension n over R, a positive integer 1 ≤i≤n and an element r ∈R, the i-th component of the element a is redefined to be r.

If a is an element of a matrix Lie algebra L of degree n over R and 1 ≤i ≤n, the ith row of the matrix a is redefined to be the vector r over R.

a[i, j] : AlgMatLieElt, RngIntElt, RngIntElt -> RngElt
a[i, j] := r : AlgMatLieElt, RngIntElt, RngIntElt, RngElt -> AlgMatLieElt
For an element a of a matrix Lie algebra L of degree n and integers 1 ≤i, j ≤n return the element in the ith row and jth column of a or set this element to be r where r is an element of the coefficient ring of L.
V2.28, 13 July 2023