Notes for AKT-170217/0:03:07

$g_{0}$ may be the 0th in the class of Lie algebras we're playing with but its enveloping algebra can be made simpler still. Consider the algebra H obtained from $U(g_{0})$ by inverting h and quotienting by the relation $l=-ef/h$ (check that $l+ef/h$ is a central element in $U(g_{0})$). And while we're at it, why not scale out the h entirely? Also, the screen is impossible to see on video but the accompanying mathematica file makes up for it twice. Roland