E=mc2=hv
The phase of a massive particle's wave function advances at the Compton frequency mc2/h, where m is the particle mass, and constitutes an elementary clock. However, practical time measurements so far are based on the dynamics of interacting multi-particle systems, such as atoms. In my talk, I will show that this description of matter waves is equivalent to the Schrödinger equation in the limit of weak gravity when the gravitational redshift and time dilation are taken into account. I will present our matter-wave test of the gravitational redshift and quantitatively discuss how it compares to previous experiments with atomic clocks and tests of the universality of free fall, using the Standard Model Extension as a theoretical framework. I will also present our ideas for a laboratory demonstration of a gravitational Aharonov-Bohm effect. It will show that matter waves are phase shifted by a gravitational potential even in absence of gravitational forces. Finally, I will present our latest experimental data from an actual "Compton clock" that delivers a 10-MHz signal that is stabilized to a fixed subharmonic of a cesium atom's Compton frequency. I will conclude that frequency and time measurements do not need to be tied to the dynamics of bound systems. Instead, the ‘global’ time evolution of a single massive particle's wave function provides an elementary, and even practically accessible, timescale.
Speaker: Dr. Holger Müller, University of California, Berkeley, USA
Location: Josef-Stefan-Hörsaal, 3rd Floor, Strudlhofgasse 4, 1090 Vienna
- Files:
Talk_Mueller.pdf