ERIK MCLEAN / UNSPLASH

Physikalisches Kolloquium

Freitag, 17. Oktober 2025 17:00 Uhr  Precision at the Extremes: Exploring the Standard Model with Trapped Exotic Ions

Prof. Dr. Klaus Blaum , Max-Planck-Institut für Kernphysik, Heidelberg Precision at the Extremes: Exploring the Standard Model with Trapped Exotic Ions Klaus Blaum1,2 1Max-Planck-Institut für Kernphysik, Heidelberg, Germany 2Universität Heidelberg, Fakultät für Physik und Astronomie, Germany The four fundamental interactions and their symmetries, along with the fundamental constants and properties of elementary particles – such as masses and magnetic moments – form the foundational structure of the universe and underpin the well-tested Standard Model (SM) of particle physics. Conducting stringent tests of these interactions and symmetries under extreme conditions, at low energies and with the highest precision, for example by comparing particles and their counterparts, the antiparticles, allows us to probe for potential physics beyond the SM. Advancing these tests beyond their current limits requires the development of innovative experimental techniques. This overview highlights recent technical advancements and measurements of atomic and nuclear masses, as well as ?-factors, with unprecedented precision, performed on individual or a few cooled exotic ions stored in Penning traps. Notably, these experiments have among others enabled the most precise tests of bound-state quantum electrodynamics and have significantly improved the accuracy of several key fundamental constants. Image: Abbildung: Der PENTATRAP Penning-Fallen-Turm für Präzisionsmassenmessungen an hochgeladenen Ionen (Foto: Ralf Lackner, MPIK)

Teilchenkolloquium

WW polarisation

Chilufya Mwewa Kapya, DESY Hamburg

Astronomisches Kolloquium

Dienstag, 21. Oktober 2025 16:30 Uhr  Gobblin' mode: how to form stars, planets and black holes quickly

Daniel Price, Monash University Take a molecular cloud, collapse it to form a star and the leftover material will form planets. Sounds easy, right? But even our own solar system is riddled with clues that forming stars and planets is a bit. more. complicated. It turns out that accreting gas to form any small object is hard. Accreting gas at the rate needed to form the Sun in a few hundred thousand years is even harder. None of this is new. What is new is the observational revolution of the last 10 years, showing us the insides of protoplanetary discs, bringing fresh clues as to how both stars and exoplanets form [seemingly, together]. This has dramatic implications for our understanding of how accretion works. I will argue that the typical pathway to form stars and planets is a violent mess, imprinted in subtle and not-so-subtle ways on disc observations and also in the leftovers from our solar system’s formation. The story is misaligned flow, accretion streamers, infall, warps and variability. If you don’t care about stars or planets but the story sounds familiar, it’s because it’s not so different for making black holes or galaxies either... To arrange a visit with the speaker during the visit, please contact their host: Mike Lau

Zentrum für Quantendynamik Kolloquium

Mittwoch, 15. Oktober 2025 16:30 Uhr  Topological pumping of quantum information

Dr. Konrad Viebahn, Institute for Quantum Electronics, ETH Zürich Topological pumping of quantum information Dr. Konrad Viebahn, Institute for Quantum Electronics, ETH Zürich Topological pumps provide a powerful method for transporting particles with remarkable precision by slowly and cyclically modulating a lattice potential. This transport is topologically protected - a feature it shares with the quantum Hall effect - making it inherently robust against noise and experimental imperfections. In this colloquium, I will introduce a novel paradigm of this concept: moving beyond the transport of individual particles to the pumping of quantum information itself. Our experiments, which employ ultracold fermions in dynamical optical lattices [1,2], demonstrate the coherent transport of not only single atoms but also entangled Bell pairs over hundreds of lattice sites. This capability allows us to perform fundamental quantum computations during transport, including high-fidelity two-qubit gates. I will show how we can chain these operations together to build non-local quantum circuits and generate complex entanglement patterns across the lattice. [1] arXiv:2409.02984 “Splitting and connecting singlets in atomic quantum circuits” [2] arXiv:2507.22112 “Protected quantum gates using qubit doublons in dynamical optical lattices”