Automorphism of a Lie algebra
In abstract algebra, an automorphism of a Lie algebra g {\displaystyle {\mathfrak {g}}} is an isomorphism from g {\displaystyle {\mathfrak {g}}} to itself, that is, a bijective linear map preserving the Lie bracket. The automorphisms of g {\displaystyle {\mathfrak {g}}} form a group denoted Aut g {\displaystyle \operatorname {Aut} {\mathfrak {g}}} , the automorphism group of g {\displaystyle {\mathfrak {g}}} .
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