Degree operator
Adjoining the degree derivation
Let 𝔤 be a 𝔄-Graded Lie algebra over 𝕂 with 𝔄 ≤𝕂+ a submonoid,
so that we may define the degree derivation 𝑑 ∈D(𝔤).
Then by adjoining the derivation 𝑑 to 𝔤
one gets a unique graded structure on 𝔤 ⋊𝕂𝑑 such that ad𝑑 is the degree operator, #m/def/lie
whence deg𝑑 =0.
Modules
Let 𝔤 be a 𝔄-Graded Lie algebra over 𝕂 with 𝔄 ≤𝕂+ a submonoid
and 𝑉 be a graded module* over 𝔤.
Then 𝑉 is also a graded module over 𝔤 ⋊𝕂𝑑 where 𝑑 acts as the Degree operator on 𝑉,
i.e. 𝑑 ⋅𝑣 =𝛼𝑣 for 𝑣 ∈𝑉𝛼. #m/thm/lie
Proof
#state/tidy | #lang/en | #SemBr