Morse index of circular solutions for attractive central force problems on surfaces

The classical theory of attractive central force problem on the standard (flat) Euclidean plane can be generalized to surfaces by reformulating the basic underlying physical principles by means of differential geometry. Attractive central force problems on state manifolds appear quite often and in several different context ranging from nonlinear control theory to mobile robotics, thermodynamics, artificial intelligence, signal transmission and processing and so on. The aim of the present paper is to analyze the variational properties of the circular periodic orbits in the case of attractive power-law potentials of the Riemannian distance on revolution's surfaces. We compute the stability properties and the Morse index by developing a suitable intersection index in the Lagrangian Grassmannian and symplectic context.