On noncommutative isotropic harmonic oscillator
  Energy spectrum of isotropic oscillator as a function of noncommutativity parameter theta is studied. It is shown that for a dense set of values of theta the spectrum is degenerated and the algebra responsible for degeneracy can be always chosen to be sU(2). The generators of the algebra are constructed explicitely. 
Agnieszka Kijanka, Piotr Kosinski