Quantization of classical integrable systems. Part III: systems in n-dimensional Euclidean space

In this paper we give examples of applications of general methods of quantization by symmetrization of classical integrable systems, which have been illustrated in two previous works by the same authors. We consider two classes of systems in n spatial dimensions, which respectively describe a point particle in a central force field and a freely rotating rigid body. In the former case, the application of the general methods to an integrable classical system leads in an almost straightforward way to the quasi-integrability of the corresponding quantum system. In the latter case instead, a modification of the symmetrization procedure is necessary in order to achieve quantum integrability for n=6.