Lafuente López, JavierAguirre Dabán, Eduardo2023-06-202023-06-202006-030926-224510.1016/j.difgeo.2005.08.001https://hdl.handle.net/20.500.14352/50110Consider a smooth manifold with a smooth metric which changes bilinear type on a hypersurface Σ and whose radical line field is everywhere tangent to Σ. We describe two natural tensors on Σ and use them to describe “integrability conditions” which are similar to the Gauss–Codazzi conditions. We show that these forms control the smooth extendibility to Σ of ambient curvatures.engjournal articlehttp://www.sciencedirect.com/science/article/pii/S0926224505000768http://www.sciencedirect.com/restricted access512Type-changing metricsCurvature extendibilityÁlgebra1201 Álgebra