L2-Invariants: Theory and Applications to Geometry and K-Theory

In algebraic topology some classical invariants - such as Betti numbers and Reidemeister torsion - are defined for compact spaces and finite group actions. They can be generalized using von Neumann algebras and their traces, and applied also to non-compact spaces and infinite groups. These new L 2-invariants contain very interesting and novel information and can be applied to problems arising in topology, K -Theory, differential geometry, non-commutative geometry and spectral theory. It is parti