Michelson-Morley experiment for electrons: Quantum-information techniques used to explore fundamental physics
A new experiment conducted at the University of California at Berkeley used quantum information techniques for a precision test of a cornerstone principle of physics, namely Lorentz invariance. This precept holds that the results of a physics experiment do not depend on its absolute spatial orientation. The work uses quantum-correlated electrons within a pair of calcium ions to look for shifts in quantum energy levels with unprecedented sensitivity. JQI Adjunct Fellow and University of Delaware professor Marianna Safronova, who contributed a theoretical analysis of the data, said that the experiment was able to probe Lorentz symmetry violation at the level comparable to the ratio of the electroweak and Planck energy scales. These correspond, respectively, to the energy scale of the universe at which the electromagnetic and weak forces become comparable in strength, and the scale where gravity becomes comparable in strength to the other physical forces.