2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/14977Scalar-tensor theories of gravity can be formulated in the Jordan or in the Einstein frame, which are conformally related. The issue of which conformal frame is physical is a contentious one; we provide a straightforward example based on gravitational waves in order to clarify the issue.11 pages, LaTeX, no figuresAstrophysicstext