Prof. Holger Müller
Associate Professor, Physics Department University of California, Berkeley
Dark energy could be a dynamic field - quintessence. The original and simplest model is based on so-called tracker potentials. Confirming this model would identify the dominant constituent of the universe and help understanding its history. In principle, this is possible by studying the history of the dark energy density, e.g., by improved supernova surveys, microwave-background-radiation or structure-formation studies.
Assuming a coupling between dark energy and normal matter, of roughly gravitational strength, allows us to detect search for quintessence by measuring its interaction with cold atoms in atom interferometers. We have already constrained the model more than 1000 times more strongly than the best previous experiment. Searching its entire parameter space is feasible and would either detect quintessence or rule out the model, thus characterizing the properties of dark energy.