Kolloquien

The Standard Model of particle physics is incredibly successful but glaringly incomplete. Among the questions left open is the striking imbalance of matter and antimatter in our universe, which inspires experiments to compare the fundamental properties of matter/antimatter conjugates with high precision. The BASE collaboration at the antiproton decelerator of CERN is performing such high-precision comparisons with protons and antiprotons.   mehr...

Modern machine learning and artificial intelligence are starting to fundamentally change how we analyze huge volumes of data in particle physics and adjacent scientific disciplines. These breakthroughs promise new insights into major scientific questions such as the nature of dark matter or the existence of physical phenomena beyond the standard model.   mehr...

Superconductivity is a fascinating state of matter that transforms metals at very low temperature into perfect conductors and perfect diamagnets. This enables numerous technical applications for magnetic levitation, electric current transport without loss and for quantum information technology. A desired but rare type of unconventional superconductivity with possible uses in topological quantum computing is one where the superconducting condensate is odd under inversion symmetry, so-called odd-parity superconductivity. Only a handful of uranium-based materials have this property and it is usually explained by the presence of ferromagnetism enforcing a parallel alignment of the electrons forming the Cooper pair.   mehr...

Recent rapid progress in applications of machine learning has also illustrated that there is an exponential growth of required resources, especially for advanced applications like large-language models. This makes it all the more urgent to explore possible alternatives to current digital artificial neural networks. The field of neuromorphic computing sets itself the goal to identify suitable physical architectures that enable us to perform machine learning tasks in a highly parallel and much more energy-efficient manner.   mehr...

Particle accelerators are ubiquitous tools across scientific, industrial, and medical domains, pivotal not only in advancing particle physics but also in applications such as sterilization and radiotherapy in modern healthcare facilities. Traditionally, these accelerators harness microwave fields to impart momentum to swift electrons or other charged particles.   mehr...

Particles in the atmosphere - aerosols - may serve as cloud condensation nuclei. Increases in aerosol concentrations thus change cloud droplet concentrations and thus enhance the brightness of clouds. Such aerosol-cloud interactions exert a cooling effect on climate.   mehr...

All chemical elements are born naked and do not bind electrons until the temperature drops sufficiently. Most of the baryonic matter remains highly charged since the re- ionization era, be it in the cores of stars, astrophysical shocks, accretion disks, or the intra-cluster and intergalactic media. Thus, the study of highly charged ions in the laboratory is essential for astrophysical diagnostics.   mehr...

Advanced statistical methods are rapidly permeating many scientific fields, offering new perspectives on long-standing problems. In materials science, data-driven methods are already bearing fruit in various disciplines, such as hard condensed matter or inorganic chemistry, while comparatively little has happened in soft matter.   mehr...

Over the last twenty years, physicists have learned to manipulate individual quantum objects: atoms, ions, molecules, quantum circuits, electronic spins... It is now possible to build "atom by atom" a synthetic quantum matter. By controlling the interactions between atoms, one can study the properties of these elementary many-body systems: quantum magnetism, transport of excitations, superconductivity... and thus understand more deeply the N-body problem. More recently, it was realized that these quantum machines may find applications in the industry, such as finding the solution of combinatorial optimization problems.   mehr...

Star formation is a vital process for stellar mass growth during the evolution of galaxies. Our understanding of where stars form and how their formation is regulated across galactic disks is surprisingly incomplete. In order to resolve the sites of recent (or future) star formation and sample the time evolution of the star formation process, high spatial resolution observations of nearby galaxies are required that reach the scales of the star-forming units, namely giant molecular clouds and HII regions.   mehr...

Nuclear magnetic resonance (NMR) has found many applications as a non-invasive tool at the interface of physics, chemistry, and the life sciences. Macroscopic spin magnetization reveals, e.g., molecular structures in solution and provides anatomical information in medical MR imaging (MRI). All these experiments require an initial perturbation of the spin magnetization to generate an inductive signal. Many classical applications work with a moderate perturbation of the Boltzmann equilibrium in combination with spontaneous or enforced recovery during which the magnetization is subject to microscopic field variations.   mehr...

Heavy ion collisions reproduce droplets of the trillions-of-degrees-hot liquid that filled the microseconds-old universe, conventionally called quark-gluon plasma (QGP) but better thought of as hot quark soup. Over the past twenty years, data obtained via recreating this primordial liquid have shown that it is the most liquid liquid in the universe, making it the first complex matter to form as well as the source of all protons and neutrons.   mehr...

Rapid progress in the experimental control and interrogation of molecules is enabling new opportunities for investigating the fundamental laws of our universe. In particular, molecules containing heavy, octupole-deformed nuclei, such as radium, offer enhanced sensitivity for measuring yet-to-be-discovered parity and time-reversal violating nuclear properties. In this colloquium, I will present recent highlights and perspectives from laser spectroscopy experiments on these species, as well as discuss the relevance of these experiments in addressing open problems in nuclear and particle physics.   mehr...