AMP: Fundamental Symmetries

AMP research on atomic clocks and quantum optics includes precise tests of fundamental symmetries of physics (Lorentz invariance) linked to questions about the origin and fate of the universe. In particular, these measurements can be used to test the standard models of physics, with profound implications for cosmology. This research also enables Very Long Baseline Interferometry (VLBI) astronomy and precise navigation of spacecraft. Measurements on low temperature collisions between hydrogen atoms contribute to the understanding of basic atomic processes.


Project Links

Walsworth group, precision tests of fundamental physics



Ron Walsworth, David F. Phillips, and collaborators


Hydrogen masers have been built in our Hydrogen Maser Lab lab since the 1960's. Providing exceptional fractional frequency stability for periods of hours to days, hydrogen masers have many uses in time keeping and basic physics. Our H Masers have been used throughout the world for spacecraft tracking, radio astronomy, atomic physics and many other applications. They have also flown in space for precise tests of general relativity. We are presently performing tests of Lorentz invariance with our hydrogen masers by searching for an orientation or velocity dependence of a maser frequency as thet maser moves with respect to the fixed stars due to the rotation of the earth or its revolution about the sun.
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