Algebry operatorów i ich zastosowania w fizyce

Colin de Verdière and Saint-Raymond have recently found a fascinating connection between modeling of internal waves in stratified fluids and spectral theory of 0th order pseudodifferential operators on compact manifolds. The purpose of this talk is to show how a slightly weaker version of their results follows from the now standard radial estimates for pseudodifferential operators. In particular, we avoid the use of Mourre theory, normal forms and Fourier integral operators and weaken analytic and geometric assumptions. Some numerical simulations will also be provided.