J. Kellendonk, S. Richard On the wave operators and Levinson's theorem for potential scattering in R^3 (329K, PDF) ABSTRACT. The paper is a presentation of recent investigations on potential scattering in R^3. We advocate a new formula for the wave operators and deduce the various outcomes that follow from this formula. A topological version of Levinson's theorem is proposed by interpreting it as an index theorem.