2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/115183There has been a surge of interest of late in an old result of Nyman and Beurling giving a Hilbert space formulation of the Riemann hypothesis. Many authors have contributed to this circle of ideas, culminating in a beautiful refinement due to Baez-Duarte. The purpose of this little survey is to dis-entangle the resulting web of complications, and reveal the essential simplicity of the main results.10 pagesNumber TheoryClassical Analysis and ODEstext