A test for the absence of the singular continuous spectrum in the Friedrichs model

For the proof of the absence of the singular continuous spectrum in the manybody scattering problem, we suggest a new method using the analogue of the triangular interlacing operators in the inverse scattering problem.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 115, pp. 61–71, 1982.