Replica of an endomorphism
of a finite-dimensional vector space
over a field
of characteristic 0
An element of the smallest algebraic Lie subalgebra containing
(see Lie algebra, algebraic). An endomorphism
is a replica of the endomorphism
if and only if each tensor over
that is annihilated by
is also annihilated by
.
Each replica of an endomorphism can be written as a polynomial in
with coefficients from the field
and without absolute term. The semi-simple and nilpotent components of an endomorphism
(see Jordan decomposition, 2) are replicas of it. A subalgebra of the Lie algebra
is algebraic if and only if it contains all replicas of all its elements. An endomorphism
of a space
is nilpotent if and only if
for any replica
of
.
Let be an algebraically closed field, let
be an automorphism of
, let
be a semi-simple endomorphism of the space
, and let
be an endomorphism of
such that any eigenvector of
corresponding to an eigenvalue
is also an eigenvector for
, but corresponding to the eigenvalue
. An endomorphism
is a replica of the endomorphism
if and only if
for some automorphism
of the field
.
References
[1] | J.-P. Serre, "Lie algebras and Lie groups" , Benjamin (1965) (Translated from French) |
[2] | , Theórie des algèbres de Lie. Topologie des groupes de Lie , Sem. S. Lie , Ie année 1954–1955 , Secr. Math. Univ. Paris (1955) |
[3] | C. Chevalley, "Théorie des groupes de Lie" , 2 , Hermann (1951) |
Comments
References
[a1] | N. Bourbaki, "Groupes et algèbres de Lie" , Hermann (1975) pp. Chapts. VII-VIII |
Replica of an endomorphism. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Replica_of_an_endomorphism&oldid=12812