We construct homomorphisms from the universal enveloping algebra of the
positive (part of the) Witt algebra to several different Artin–Schelter regular
algebras, and determine their kernels and images. As a result, we produce
elementary proofs that the universal enveloping algebras of the Virasoro algebra,
the Witt algebra, and the positive Witt algebra are neither left nor right
noetherian.
Keywords
Artin–Schelter regular, Jordan plane, non-noetherian,
universal enveloping algebra, Witt algebra