The Tremblay-Turbiner-Winternitz system on spherical and hyperbolic   spaces : Superintegrability, curvature-dependent formalism and complex   factorization
  The higher-order superintegrability of the Tremblay-Turbiner-Winternitz system (related to the harmonic oscillator) is studied on the two-dimensional spherical and hiperbolic spaces, $S_\k^2$ ($\k>0$), and $H_{\k}^2$ ($\k<0$). The curvature $\kappa$ is considered as a parameter and all the results are formulated in explicit dependence of $\kappa$. The idea is that the additional constant of motion can be factorized as the product of powers of two particular rather simple complex functions (here denoted by $M_r$ and $N_\phi$). This technique leads to a proof of the superintegrability of the Tremblay-Turbiner-Winternitz system on $S_\k^2$ ($\k>0$) and $H_{\k}^2$ ($\k<0$), and to the explicit expression of the constants of motion. 
Manuel F. Ranada
math-ph math.MP