I modi quasi-normali dei buchi neri

In this thesis we study the quasi-normal mode of black holes, showing an application to the event GW150914 detected by the LIGO collaboration. In the first chapter we give a brief introduction to Lie Groups and Algebras, useful for understanding the basic group techniques, which are used later in the work. In the second Chapter we then discuss the theory behind the quasi-normal modes applied to black hole solutions of general relativity, showing the main techniques used for their analysis. Finally, in the third Chapter we present an application of the concepts developed to the ringdown phenomenon in reference to the event GW150914 studied by LIGO.