Seminars

Chemistry seminar by Prof. Yves Geerts (Université Libre de Bruxelles) on historical attempts by Pasteur and Curie to direct chiral symmetry breaking with external fields, why they failed, and how chirality-induced spin selectivity (CISS) under non-equilibrium conditions now enables enantiomer separation and control of molecular handedness.

Antonio Pedro Ramos examines point-evaluation bounds for integrable functions of spherical exponential type in the multivariable Paley–Wiener space. Radial extremizers connect the problem to a weighted space in one variable. The talk establishes a third-order linear differential equation with polynomial coefficients in every dimension, extending the previously known odd-dimensional result. It also develops interpolation and reciprocal identities using the extremizer’s zeros. The research is joint work with Felipe Gonçalves and Danylo Radchenko.

Florian Marquardt surveys approaches to reducing the energy and computational cost of neural networks by implementing their functions in physical devices. The central question is how experiments can efficiently determine updates to adjustable parameters, allowing the hardware itself to learn. Examples include learning through time reversal, obtaining nonlinear computation from linear optical scattering, and training analog quantum simulators as neuromorphic systems. The seminar is available in person and through the registration link on the organizer’s event page.

Salvatore Torquato gives a public lecture in the Simons Foundation's 2026 Randomness series, connecting the geometry of complex systems with random structures and applications across mathematics, computer science, physics and chemistry.

Jennifer Brophy presents two methods for programming when and where genes are expressed in plants and their associated microbes. One creates a chemical signal using the noncanonical amino acid O-methyl-L-tyrosine. Engineered Arabidopsis, tomato and poplar produce the signal, while engineered Bacillus subtilis and soil bacteria respond by activating gene expression. Restricting signal production to selected plant tissues allows local control of microbial activity. The second approach builds a genetic circuit that counts successive branching events in roots. It produces different expression patterns at different branch orders, helping researchers distinguish the contributions of roots that otherwise have similar molecular identities. Together, the approaches support experiments on plant development and the engineering of plant–microbe partnerships.

Mariana Wolfner presents research on the molecular changes in eggs, sperm, and females that coordinate successful reproduction, drawing on genetic and physiological studies of fertilization. This NIH Wednesday Afternoon Lecture Series event is offered in person and through NIH VideoCast.

Harvard T.H. Chan School of Public Health Department of Epidemiology seminar by Jeremy Labrecque, PhD, MSc (Assistant Professor of Epidemiology and Causal Inference, Erasmus MC, Rotterdam) on 'dark causal inference' — implied but unstated causal reasoning that pervades epidemiology — the misuse of 'association' language, and gaps in teaching causal reasoning.

Qihao Ye examines practical, affordable ways for individual mathematicians to use AI in literature searches, proof development and verification. The talk identifies seven recurring failure modes and introduces the open-source QED multi-agent system designed to address them. A case study on constructing Carleman weights for wave equations on the half-line shows how automated search can be combined with a researcher’s mathematical insight and rigorous checking. The organizer links both the implementation and the accompanying research paper. Online via Rutgers DIMACS Zoom. Wednesday 23 September 2026, 10:00–11:00 EDT (America/New_York; UTC−4). Use the Zoom link and passcode on the official event page. Organized by the DIMACS AI and Mathematics Seminar. This listing advertises the verified remote attendance option.

Very Long Baseline Interferometry (VLBI) provides milliarcsecond scale angular resolution imaging. This proves suitable to monitor structural evolution on AU scales in our Galaxy and on parsec scales in extragalactic sources. Given the high brightness temperatures required for detection on such small angular scales, VLBI observations are typically focused on non-thermal sources like relativistic jets and shocked emission regions in the environment of compact sources. I will present a few selected results over various mass scales, including novae, such as 2021 RS Oph and the upcoming T CrB outburst; binary neutron star mergers, like the famous GW 170817 event; jets launched in the vicinity of supermassive black hole, such as the radio galaxy M87. Moving from these results and the associated challenges, I will describe the impact of the SKA for VLBI studies for transients and radio loud AGNs.

Saee Dhawalikar (University of Salamanca) presents this Special MPA Cosmology Seminar in Lecture Hall E.0.11 at MPA, Garching. The organizer lists a 30-minute slot, normally comprising a 20-minute presentation and 10 minutes of discussion. This occurrence takes place on Wednesday rather than the series’ usual Tuesday. The published listing supplies the topic and schedule but no separate scientific abstract.

Oliver Zier (CfA) presents this Special MPA Cosmology Seminar in Lecture Hall E.0.11 at MPA, Garching. The organizer lists a 30-minute slot, normally comprising a 20-minute presentation and 10 minutes of discussion. This occurrence takes place on Wednesday rather than the series’ usual Tuesday. The published listing supplies the topic and schedule but no separate scientific abstract.

Meagan McManus examines mitochondrial dysfunction as an early driver of brain ageing and neurodegeneration. Reactive oxygen species and other mitochondrial stress signals connect impaired energy metabolism with glial activation. The talk presents preclinical evidence for [18F]ROStrace PET, a redox-sensitive tracer that crosses the blood–brain barrier, as a non-invasive way to detect mitochondrial and immune distress before overt pathology in models relevant to late-onset Alzheimer’s and Parkinson’s diseases. Online via the University of Arizona Zoom meeting. Use the Zoom link published on the organizer’s event page. Tuesday 22 September 2026, 16:00–17:00 MST (America/Phoenix; UTC−7). Organized by the Graduate Interdisciplinary Program in Neuroscience and the Department of Neuroscience. This listing advertises the verified remote attendance option.

MIT Biology Colloquium Series talk by David Bilder (University of California, Berkeley), hosted by Yukiko Yamashita, on invertebrate oncology and the ancient evolutionary origins of tumor-host interactions.

Michael Hutchings introduces Reeb vector fields and explains why their periodic orbits are substantially better understood in three dimensions through Seiberg-Witten theory. The colloquium develops Irie's closing lemma, which creates a periodic orbit through a selected region after a small perturbation, and discusses a quantitative refinement connecting the perturbation size to an upper bound on the orbit period.

ISTA Lecture by Klaus Robert Müller (TU Berlin & Korea University, Seoul) on how machine learning and AI enable scientific research, particularly in medicine and chemistry, and on explainability techniques for extracting understanding from machine learning models.

Arefe Abghari tests whether the reported excess in the quasar number-density dipole challenges the Cosmological Principle. If large-scale homogeneity and isotropy hold, the motion responsible for the cosmic microwave background dipole should also predict the dipole in distant-source counts. The analysis examines quasar selection and dipole-estimation systematics. Higher multipoles in the quasar density map, plausibly caused by survey and selection effects, can explain the apparent discrepancy. The talk argues that these effects need careful control before interpreting the measurements as evidence against the standard cosmological model.

Shane Davis presents simulations of stellar disruption and the subsequent return of debris to a black hole. Observed light curves and spectra offer tests of accretion physics and black-hole spacetime, but interpreting them requires accounting for strong radiation forces during rapid fallback. Using Athena++ and AthenaK, the research models radiation transfer, including recent calculations in Kerr spacetime. Although the debris circularizes slowly, shocks involving the returning stream and an eccentric disk dominate early energy release and angular-momentum transport. Radiation drives unbound outflows and builds a weakly bound envelope that reprocesses emission. These results offer an explanation for the strong optical and ultraviolet signals observed in many tidal disruption events.

Z Yan Wang presents comparative neuroscience research on the brains and behaviors of octopuses and bumblebees to illuminate life-history processes. The talk is part of Columbia's Tuesdays@10 neuroscience seminar program for researchers across fields and career stages.

Bryce Mander presents research on early sleep biomarkers associated with Alzheimer's disease pathophysiology and memory impairment. The William C. Dement Seminar connects sleep and circadian neuroscience with neurodegeneration, cognition and clinically relevant approaches to detecting disease-related change.

Two-dimensional topological order has caught much attention in connection to topological phases of matter and topological quantum computation, in particular. It is known that tensor networks are useful tools to study mathematical structures appearing in these topics. We present recent understanding of them from a viewpoint of operator algebras. No knowledge on operator algebras are assumed.