From Clocks to the Cosmos: Atomic Theory in the 21st Century

Advances in AMO quantum sensing and the discovery potential they offer depend on high-precision atomic theory and easy access to reliable, critically evaluated atomic data. Robust, scalable theoretical tools are essential for proposing new experiments, interpreting current new physics searches, and for identifying the systems, transitions, and measurement strategies that maximize sensitivity. The NIST Atomic Spectroscopy Group enabled this work through benchmark measurements, theory, and curating authoritative atomic databases critical for precision modeling across AMO physics, astrophysics, plasma physics, and other fields.

I will review the remarkable recent progress in atomic theory, highlighting its numerous applications to quantum technologies and new physics searches enabled by enhanced computational capabilities. I will highlight several applications from development of atomic clocks that will not lose a second in the lifetime of the Universe to solving a 40-year-old astrophysics puzzle. Recent developments include large-scale high-performance computing, the transformation of research codes into widely accessible software, the open sharing of data through a community portal, and the application of machine learning in atomic theory.