On the theory of self-dajoint extensions of the Laplace-Beltrami operator quadratic forms and symmetry

Résumé

The main objective of this dissertation is to analyse thoroughly the construction of self-adjoint extensions of the Laplace-Beltrami operator defined on a compact Riemannian manifold with boundary and the role that quadratic forms play to describe them. Moreover, we want to emphasise the role that quadratic forms can play in the description of quantum systems. ------------------------------------------------------------------------------------------------------------