Neutrons are excellent probes to test gravity at short distances – electrically neutral and only hardly polarizable. Furthermore, very slow, so-called ultracold neutrons form quantum states bound by the gravity potential of the Earth. This allows combining gravity experiments with powerful resonance spectroscopy techniques, as well as tests of the interplay between gravity and quantum mechanics. In the last decade, the qBounce collaboration has been performing several measurement campaigns at the ultracold and very cold neutron facility PF2 at the Institut Laue-Langevin.
A new spectroscopy technique, Gravity Resonance Spectroscopy, was developed and snapshots of falling wavepackets of these gravitationally bound quantum states were recorded. The results were applied to test gravity at micron distances as well as various Dark Energy and Dark Matter scenarios in the lab, like Axions, Chameleons and Symmetrons.
In my talk, I will summarize the physics that can be addressed, and review the experiments and its results.
Dr. Jitae Park
Dr. Dominic Hayward