Lie algebra Central ideal A central ideal 𝔞 ⊴𝔷(𝔤) ⊴𝔤 of a Lie algebra 𝔤 is a linear subspace of its centre Cent𝔤. #m/def/lie Any such subspace is necessarily an ideal, since [𝔞,𝔤] ={0}. #state/tidy | #lang/en | #SemBr