2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/198231It is argued that (a) In the quantum realm test-particle masses have non-trivial observability which induces a non-geometric element in gravity, (b) Any theory of quantum gravity, on fundamental grounds, must contain an element of non-locality that makes position measurements non-commutative, and (c) The classical notion of free fall does not readily generalize to the quantum regime.Invited paper to appear in the Festscrift celebrating 90th birthday of Professor Ta-You WuGeneral Relativity and Quantum Cosmologytext