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  • Perspective
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Atoms and molecules in the search for time-reversal symmetry violation

Nature Reviews Physics volume 1, pages 510–521 (2019)Cite this article

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Abstract

New fundamental particles at the mass scale of a few TeV c–2 could account for observed phenomena that cannot be explained by the standard model (SM) of particle physics, including the microscopic origin of dark matter and the macroscopic imbalance of matter over antimatter in the Universe. However, no beyond-the-SM (BSM) particles at the TeV scale have yet been detected at the Large Hadron Collider (LHC). With recent innovations, searches for time-reversal symmetry (T) violation through low-energy precision measurements of electric dipole moments (EDMs) of atoms and molecules have attained the sensitivity to detect indirect signatures of certain particles with masses of more than  10 TeV c–2. In this Perspective, we discuss recent developments in the measurement and interpretation of EDMs, and assess proposed techniques for future experiments that could push experimental limits on T-violating BSM physics to the PeV scale.

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Fig. 1: Context of EDM experiments.
Fig. 2: Interpretation of EDM experiments.
Fig. 3: Signatures and detection of T-violating permanent EDMs in atoms and molecules.
Fig. 4: Recent progress in AMO EDM experiments.
Fig. 5: Future methods for EDM searches.

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Acknowledgements

The authors thank E. A. Cornell, N. R. Hutzler, A. Vutha, E. A. Hessels, C. D. Panda and D. DeMille for valuable discussions.

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  1. JILA (NIST and University of Colorado) and Department of Physics, University of Colorado, Boulder, CO, USA

    William B. Cairncross & Jun Ye

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Cairncross, W.B., Ye, J. Atoms and molecules in the search for time-reversal symmetry violation. Nat Rev Phys 1, 510–521 (2019). https://doi.org/10.1038/s42254-019-0080-0

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