2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/187773Using the nonlinear $δN$ formalism, we consider a simple exactly soluble model of multi-component slow-roll inflation in which the nonlinear curvature perturbation can be evaluated analytically.4 pages, no figure, typos corrected, references added, final version to be published in CQGAstrophysicsGeneral Relativity and Quantum CosmologyHigh Energy Physics - Phenomenologytext