Physics Colloquia

Physics Colloquium - Julian May Mann, Stanford University Presentation title and abstract will be announced when they are available.

Effect of Phosphorylation Barcodes on Arrestin Binding to a Chemokine Receptor
Dr. Qiuyan Chen
Assistant Professor of Biochemistry & Molecular Biology
Indiana University School of Medicine

Cells often fine-tune their responses to signals through chemical tags called phosphorylation 'barcodes' placed on receptors at the cell surface. Different G-protein coupled receptor (GPCR) kinases (GRKs) add these barcodes at different sites, but how these patterns influence arrestins — key proteins that control receptor signaling and trafficking — has been unclear.

AI Reasoning in Theoretical Physics with the TPBench Project
Assistant Professor Moritz Münchmeyer
UW-Madison Department of Physics

Large-language models are becoming powerful enough to assist physicists with mathematical reasoning at the research level. In this talk, I will first present our dataset TPBench (tpbench.org), which was constructed to benchmark and improve AI models specifically for theoretical physics.

What Are We Learning About Super-Eddington Accretion Disks From Simulations?
Professor Chris Fragile
Department of Physics & Astronomy, College of Charleston

Accretion of gas onto black holes is one of the most important processes shaping our Universe. Understanding extremely high rates of accretion (dubbed 'super-Eddington') is vital to explaining the challenging observation that supermassive black holes (SMBHs) are fully formed at redshifts >7. It is also important to understanding astrophysical objects such as tidal disruption events (TDEs) and ultra-luminous X-ray sources (ULXs).

Physics Colloquium - Lulu Agazie, UWM Physics Presentation title and abstract will be announced when they are available.

Physics Colloquium - Ronan Humphrey, UWM Physics
Presentation title and abstract will be announced when they are available.

Combining Quantum Master Equations with Linearized Semiclassical Methods to Simulate Electronic Energy & Charge Transfer Dynamics in Complex Molecular Systems
Professor Eitan Geva, Department of Chemistry
University of Michigan - Ann Arbor

Photo-induced electronic energy and charge transfer plays a key role in a variety of chemical, biological and technologically-important molecular systems. The simulation of the
underlying electronic dynamics is challenging due to its intrinsically quantum mechanical nature and the large number of coupled electronic and nuclear degrees of freedom involved. Quantum master equations provide a flexible and general-purpose framework for addressing this challenge.

Manifold-based Machine Learning for Scattering Data
Adam Opperman, PhD Candidate
University of Wisconsin-Milwaukee Department of Physics & Astronomy

Small Angle X-ray Scattering (SAXS) is a technique used to capture X-ray diffraction images of proteins in solution, mimicking biological conditions. These images provide insight into the overall shape and structure of the protein. By imaging the protein system at various times during a reaction, dubbed time-resolved SAXS (TR-SAXS), the evolution of the protein structure is observed. These measurements are commonly taken at X-ray Free Electron Laser (XFEL) facilities which generate X-rays with precision and high flux. The Compact X-ray Light Source (CXLS) and accompanying Compact X-ray Free Electron Laser (CXFEL) are under construction at Arizona State University. Due to the compact nature of the source in combination with the yet incomplete development, CXFEL has a reduced level of photon flux available compared to other XFELs. Due to this constraint, new analytical methods are needed to process TR-SAXS data.

Studying Magnetism with Resonant X-ray Scattering at Advanced Photon Source
Jong-Woo Kim, Physicists
Magnetic Material Group/Advanced Photon Source, Argonne National Laboratory

X-ray scattering at synchrotron facilities such as the Advanced Photon Source provides a powerful platform for investigating magnetic order with element and orbital specificity. In this colloquium, I will introduce the fundamentals of single-crystal X-ray diffraction and the principles of resonant elastic X-ray scattering (REXS), emphasizing how tuning to absorption edges enhances sensitivity to electronic and magnetic structures.

Constraining Common Envelope Evolution Simulations with Observations
Sarah Villanova Borges, PhD Candidate
University of Wisconsin-Milwaukee

Common Envelope Evolution (CEE) remains one of the biggest unresolved problems in binary stellar evolution, despite being the primary pathway for the formation of close binary systems. One of the main challenges in understanding CEE is its intrinsically multiscale and multiphysics nature, which makes it difficult to model with analytical or 1D models. 3D hydrodynamical simulations have therefore become essential tools for studying this phase. However, validating these simulations requires observational constraints, which are scarce. This lack of direct observations is another major obstacle in modeling CEE. One exception is luminous red novae, which is believed to correspond to CEE events that culminate in stellar mergers.