Programm für das Sommersemester 2025
Tuesdays, 16:15 Uhr s.t.
Institut für Physik
| 15.04.25 | Andrew Webb, Leiden University Medical Centre, NL | |
Magnetic resonance imaging is an inherently non-invasive technique with biological applications from the cellular to human size-scales. A major technological push has been towards stronger magnetic fields, which can be >20 Tesla for preclinical studies and >10 Tesla for humans, since these increase the signal strength and ultimate imaging resolution. Such systems, however, require advances in hardware design, acquisition sequences and image processing algorithms to achieve optimal performance. The first part of this talk will concentrate on technical challenges and practical approaches for human scanning at 7 Tesla and above. The challenges include B_1 and B_0 inhomogeneities, increased specific absorption rate, and high sensitivity to movement. Neurological and neuroscience applications discussed include ocular and neurological tumours, epilepsy, neuromuscular diseases, glymphatic clearance and mechanistic studies of lithium for bipolar disorders. The second part will discuss the opposite end of the MRI spectrum, ultra-low field systems at ~50 mT which have been designed to address the challenges of global healthcare accessibility. The challenges here are diametrically opposite to those at high field, and topics of system design, characterization and in vivo applications will be highlighted. | ||
| 16:15 Uhr s.t., HS KPH | ||
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zukünftige Termine
| 29.04.25 | Frauke Gräter, Max Planck Institute for Polymer Research | |
Life is physics and chemistry in action. While molecular simulations of systems as complex as whole cells are now within reach, predicting chemical reactivity on relevant time and length scales remains a challenge. I will present our recent work towards bringing action – here: chemistry – to classical simulations and molecular design through machine learning.
Among others, we substitute costly quantum mechanical calculations with a graph neural network-based emulator. Our framework can deal with the plethora of life’s chemistry amidst the ‘jiggling and wiggling’ of biomolecules. Importantly, we also uncover unexpected biomolecular processes that we in turn put to test in experiments. Finally, I will demonstrate how we harness a flow-matching model to predict biomolecular dynamics. Our method paves the way for generating novel flexible and functional proteins. | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 06.05.25 | Yafang Cheng, Max Planck Institute for Chemistry | |
Aerosol chemistry: from molecular dynamics to atmospheric vortices | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 13.05.25 | Anna Balazs, University of Pittsburgh, USA | |
Harnessing Chemo-Mechanical Interactions To Regulate Behavior Of Flexible Materials In Confined Fluids | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 20.05.25 | Libor Smejkal, JGU Mainz, INSPIRE Group | |
tba | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 27.05.25 | Subir Sarkar, University of Oxford | |
In the ΛCDM cosmological model the Universe is assumed to be isotropic and homogeneous when averaged on large scales. That the Cosmic Microwave Background has a dipole anisotropy is interpreted as due to our peculiar (non-Hubble) motion because of local inhomogeneity. There must then be a corresponding dipole in the sky distribution of sources at high redshift. Using catalogues of radio sources and quasars we find that this expectation is rejected at >5σ, i.e. the distribution of distant matter is not isotropic in the 'CMB frame’. This calls into question the standard practice of boosting to this frame to analyse cosmological data, in particular to infer acceleration of the Hubble expansion rate using Type Ia supernovae, which is then interpreted as due to a Cosmological Constant Λ. We find that the inferred acceleration is anisotropic (in the direction of the CMB hotspot) and likely illusory because of our being embedded in a coherent bulk flow, rather than due to dark energy. | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 03.06.25 | Christian Weinheimer, Universität Münster | |
tba | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 10.06.25 | Günter Reiss, Universität Bielefeld | |
Magnetic Heterostructures: From Sensors and Memories to Altermagnets | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 17.06.25 | Serge Haroche, Laboratoire Kastler Brossel, Collège de France | |
TBA | ||
| 16:15 Uhr s.t., Staudinger Hörsaal | ||
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| 24.06.25 | Nir Barnea, The Hebrew University of Jerusalem | |
Behaviour of Correlated Nucleon Pairs Inside Nuclei | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 01.07.25 | Dennis Lehmkuhl, Universität Bonn | |
Philosophy of Physics | ||
| 16:15 Uhr s.t., HS KPH | ||
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| 08.07.25 | Volker Springel, Max Planck-Institut für Astrophysik, Garching | |
Numerical calculations of cosmic structure formation have become a powerful tool in astrophysics. Starting right after the Big Bang, they are not only able to accurately predict the dark matter backbone of the cosmic web far into the non-linear regime, but are also capable of following baryonic physics with rapidly improving fidelity. In my talk, I will review the methodology and selected results of recent structure formation simulations that follow large parts of the observable universe. I will discuss some of the primary challenges in modelling strong, scale-dependent feedback processes that regulate star formation in galaxies, and highlight the important role played by supermassive black holes in galaxy formation. I will also discuss extremely large simulations and describe how they help to make reliable predictions for the impact of baryons and massive neutrinos on cosmological observables, effects that need to be understood to make full use of upcoming new survey data. The simulation results also shed light on cosmic reionization and magnetic field amplification during non-linear structure formation. Finally, I will highlight some of the methodological and technical challenges involved in obtaining future multi-physics, multi-scale simulations that aim for more accurate predictions. | ||
| 16:15 Uhr s.t., HS KPH | ||
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| Koordination: | Kontakt: |
Prof. Dr. Friederike Schmid Prof. Dr. Hartmut Wittig | Daniela Reibel Fulya Mank |