Physics Colloquium - Hunting for Dark Energy in the Lab

Event Date: 

Tuesday, April 5, 2016 - 4:00pm

Event Location: 

  • Broida 1640


Holger Muller

Muller Group, UC Berkeley



Dark energy could be a dynamic field - quintessence. The original and simplest model is the so-called tracker potential. Confirming this model would identify the dominant constituent of the universe, help understanding its history, and be a milestone in particle physics. 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. While these measurements are important, no single approach is guaranteed to identify the quintessence field.

Making the reasonable assumption of an additional coupling between dark energy and normal matter, of roughly gravitational strength, allows us to detect 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 the entire range of allowed interaction strengths is feasible. We would then either detect the field or rule out its existence (always assuming that quintessence does indeed interact - but showing that it doesn't would be interesting in its own right if quintessence is confirmed by cosmological data, because it would characterize its properties).