Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An update on the classical and quantum harmonic oscillators on the
  sphere and the hyperbolic plane in polar coordinates   A simple derivation of the classical solutions of a nonlinear model
describing a harmonic oscillator on the sphere and the hyperbolic plane is
presented in polar coordinates. These solutions are then related to those in
cartesian coordinates, whose form was previously guessed. In addition, the
nature of the classical orthogonal polynomials entering the bound-state radial
wavefunctions of the corresponding quantum model is identified.

29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org