2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/61828The Laplacian (or radial) masa in a free group factor is generated by the sum of the generators and their inverses. We show that such a masa B is strongly singular and has Popa invariant delta(B) = 1. This is achieved by proving that the conditional expectation onto B is an asymptotic homomorphism. We also obtain similar results for the free product of discrete groups, each of which contains an element of infinite order.16 pages, latex fileOperator Algebras46L05text