The case of equality in Young's inequality for the s-numbers in semi-finite von Neumann algebras

Abstract

For a semi-finite von Neumann algebra A, we study the case of equality in Young´s inequality of s-numbers for a pair of τ-measurable operators a,b, and we prove that equality is only possible if |a|^p=|b|^q. We also extend the result to unbounded operators affiliated with A, and relate this problem with other symmetric norm Young inequalities.Fil: Larotonda, Gabriel Andrés. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; Argentin