Probing Quantum Aspects of Gravity

Abstract

We emphasize that a specific aspect of quantum gravity is the absence of a super-selection rule that prevents a linear superposition of different gravitational charges. As an immediate consequence, we obtain a tiny, but observable, violation of the equivalence principle, provided, inertial and gravitational masses are not assumed to be operationally identical objects. In this framework, the cosmic gravitational environment affects local experiments. A range of terrestrial experiments, from neutron interferometry to neutrino oscillations, can serve as possible probes to study the emergent quantum aspects of gravity.

Comments: Phys. Lett. B (in press). S. Sarkar's name was inadvertently missed from the list of authors for "Nature 393 (1998) 763-765." This has been now corrected