2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156209We show that there is a canonical construction of a zeta (Bismut-Quillen) connection on the determinant line bundle of a family of APS elliptic boundary problems and that it has curvature equal to the 2-form part of a relative eta form.Minor technical clarificationsDifferential Geometrytext