Newsroom
Stay informed with our latest news and announcements on this page. For more in-depth content, we also encourage visitors to explore our bimonthly STRUCTURES Newsletter magazine, which features a variety of articles, interviews with members, and background information on our latest research and activities.
STRUCTURES Professor Michela Mapelli Takes Leading Role in Europe's Next-Generation Gravitational-Wave Observatory
Michela Mapelli, STRUCTURES Professor at Heidelberg University (Centre for Astronomy and Interdisciplinary Center for Scientific Computing) has been appointed Chair of the Observation Science Board (OSB) of the Einstein Telescope Collaboration, one of the major international projects shaping the future of gravitational-wave astronomy.
The Einstein Telescope is the planned next-generation European gravitational-wave observatory. Designed to be about ten times more sensitive than current gravitational-wave detectors, the Einstein Telescope is expected to detect gravitational-wave events from across most of the observable Universe and to investigate fundamental questions in astrophysics, cosmology, and fundamental physics. The Einstein Telescope has been included in the European Strategy Forum on Research Infrastructures (ESFRI) Roadmap since 2021 and has been identified as one of the key infrastructures of the future by the German Ministry for Research, Technology and Space.
With more than 700 members, the Observation Science Board plays a central role within the collaboration: it coordinates the development of the scientific goals of the Einstein Telescope, including studies of compact objects, cosmology, multimessenger astronomy, data analysis, and synergies with other electromagnetic and gravitational-wave observatories.
Mapelli has been a member of the Einstein Telescope Collaboration since its foundation in 2022 and has served as one of the lead editors of the “Blue Book”. Her research focuses on understanding the formation and evolution of binary black holes and intermediate-mass black holes across cosmic time. Since 2023, Heidelberg University has hosted one of the main research units of the Einstein Telescope Collaboration in Germany, with more than 20 members spread across the Zentrum für Astronomie, the Institut für Theoretische Physik, the Max Planck Institute for Astronomy, and the Heidelberg Institute for Theoretical Studies.
“I am deeply honored to serve as Chair of the Observation Science Board,” says Mapelli. “The Einstein Telescope will open an entirely new window on the Universe, and I look forward to working with the international community and with my co-chairs, Archisman Ghosh (Ghent University) and Paolo Pani (La Sapienza University of Rome), to help shape its scientific vision.”
Further information:
Geometry, Dynamics, and Computer-Assisted Proofs – A Conference in Honour of Rich Schwartz
Heidelberg University will host the international conference “Geometry, Dynamics, and Computer-Assisted Proofs – a conference in honour of Rich Schwartz” from June 10–12, 2026, at Mathematikon, Heidelberg.
Over the past decades, the fields of geometry, dynamics, and geometric group theory have developed increasingly deep connections, with ideas and methods flowing productively between them. At the same time, computer-aided proofs have grown into a powerful tool that enables mathematicians to explore problems previously inaccessible. Reflecting these developments, Heidelberg's Research Station Geometry + Dynamics (GeoDyn) will host the international conference “Geometry, Dynamics, and Computer-Assisted Proofs – a conference in honour of Rich Schwartz”:
Date: June 10–12, 2026.
Location: Mathematikon Lecture Hall.
The conference seeks to bring together researchers and students working in geometry, dynamics, geometric group theory, and computational mathematics to explore their rich interplay and the ways in which computational methods can advance our understanding of key problems. The programme features internationally renowned speakers from Harvard University, Princeton University, the University of Oxford, and the Weizmann Institute of Science.
The event celebrates the influential contributions of Rich Schwartz, whose work has shaped several of these fields and inspired new interactions between geometry, dynamics, and computational approaches.
The organizing commitee consists of Peter Albers ( STRUCTURES, Heidelberg University), Martin Bridgeman (Boston College), Diana Davis (Phillips Exeter Academy), William Goldman (University of Maryland), Patrick Hooper (CUNY), Jeremy Kahn (Brown University), Serge Tabachnikov (Penn State University) and Anna Wienhard (MPI Leipzig).
Further details, including a schedule, will be made available on the conference webpage: https://sites.google.com/view/rich-problems/.
Further information:
Scientific Machine Learning Event “Machine Learning Galore!” on June 24, 2026: Agentic AI
We are delighted to announce the next event in our Machine Learning Galore! series, focusing on Scientific Machine Learning, which will take place on Wednesday, June 24, from 4:30 to 6:00 pm at INF 205 Mathematikon (5th floor). The event will feature presentations and discussions on the topic of “Agentic AI”
Event Details:
- Agentic AI:
- Christian Schulz
- Daniel Schiller
- Inga Ulusoy
- Marc Ickler
- Tobias Renkert
- Vincent Heuveline
- Case studies:
- Writing code faster - Optimizing your code - Hosting your own - Injecting domain knowledge - What does not work (yet)
Registration is free but required via the ML-AI portal – please register until June 19:
https://www.mlai.uni-heidelberg.de/en/machine-learning-talks-on-campus
About Scientific Machine Learning:
Scientific Machine Learning is a collaborative initiative by the Interdisciplinary Center for Scientific Computing (IWR) and the STRUCTURES Cluster of Excellence. Its mission is to foster interaction and exchange within the local machine learning community, and to support its development by consolidating activities and resources that might otherwise remain scattered across individual institutions or disciplines. The initiative aligns closely with the objectives of STRUCTURES, which aims to advance fundamental research, and with IWR’s focus on applying machine learning to address long-standing challenges in the natural and life sciences, engineering, and the humanities.
Further information:
Image credits: Derek Davis / University of Rhode Island / LIGO – Virgo – KAGRA.
The international LIGO–Virgo–KAGRA (LVK) Collaboration has released its latest catalogue of gravitational-wave detections, adding 161 new events observed between April 2024 and January 2025. The new data reveals evidence for the existence of second-generation black holes, provides the most precise sky localization ever achieved for a gravitational wave source, and offers the first measurement of three vibrational modes of a black hole.
The international network of gravitational wave detectors LIGO, Virgo and KAGRA (LVK) has announced today the online release of an updated catalogue of all gravitational wave events observed to date, named the Gravitational Wave Transient catalogue-5.0 (GWTC-5), with the corresponding scientific papers in submission to Astrophysical Journal and Astrophysical Journal Letters. The data analysed in this work were collected by the detectors between April 2024 and the end of January 2025, during a portion of the fourth observing run known as O4b. During this period, 161 new gravitational wave events were detected, bringing the total number of confirmed events observed by the network since the first detection in 2015 to an astounding 390. The international LVK network consists of the twin detectors of the US National Science Foundation Laser Interferometer Gravitational-wave Observatory (NSF LIGO) , the Virgo detector hosted by the European Gravitational Observatory in Italy and the Japanese KAGRA hosted by the Institute for Cosmic Ray Research (ICRR) of the University of Tokyo.
The new catalogue of gravitational wave events allows researchers to study black hole populations in unprecedented detail. “The new catalogue is a gold mine of discoveries, but it also poses new challenges,” says Michela Mapelli, STRUCTURES professor at the Center for Astronomy of Heidelberg University and directly involved in the studies. “For example, the spins – that is, the magnitudes and orientations of the rotations – of the components of two new binary black hole systems, GW241011 and GW241110, are exactly what we expect for second-generation black holes: black holes formed through the merger of smaller black holes.” At the same time, the new study finds that the masses of these black holes, about 10–20 times the mass of the Sun, are lower than predicted by most theoretical models. “This is a new enigma that will keep compact-object astrophysicists busy for quite some time!” says Michela Mapelli.
The new study also provides the most precise sky localization ever obtained for a gravitational-wave source. A signal known as GW240615 was identified within an area of just 6 square degrees, a very small portion of the celestial sphere. This exceptional performance was achieved thanks to the triangulation using data from all three detectors. At the same time, the catalogue includes the “clearest” gravitational wave signal ever detected, with a signal-to-noise ratio of 76.9. This signal, GW250114, reached Earth on January 14, 2025 and was generated by the merger of two black holes with nearly identical masses. After the collision, a newly formed black hole “rings” as it settles into its final shape – similar to how a bell vibrates and produces different tones. For the first time, scientists were able to measure multiple such “tones” – or vibrational modes – in a black hole signal, offering a new way to test Einstein’s theory of general relativity under extreme conditions. The results were in agreement with the predictions of general relativity.
Michela Mapelli is a STRUCTURES Professor working at the Center for Astronomy of Heidelberg University (ZAH), where she leads the group “DEMOBLACK - Demography of Black Hole Binaries in the Era of Gravitational-Wave Astronomy”. Her main research focus is understanding the formation of astrophysical black holes. Prof Mapelli joined STRUCTURES in 2023.
The LIGO–Virgo–KAGRA (LVK) Collaboration is the international network operating the world’s leading gravitational-wave observatories: the two LIGO detectors in the United States, Virgo in Italy, and KAGRA in Japan. Together, the collaboration brings together several thousand researchers from hundreds of institutions worldwide to detect and study gravitational waves from colliding black holes, neutron stars, and other compact-object mergers.
Further information:
The biggest black holes in the Universe may not be born from collapsing stars. A new study involving STRUCTURES professor Michela Mapelli and collaborators at Cardiff University suggests they instead form through violent merging events in very densely populated star clusters.
The researchers analysed the new LIGO-Virgo-KAGRA Gravitational Wave Transient Catalog to test whether the heaviest black holes were, in reality, second generation objects formed after successive merging processes in a star cluster. In the data analysed, the authors found two different populations, a low-mass one consistent with ordinary stellar collapse and a higher-mass population, whose rapid, randomly oriented spins are a signature of repeated merging in dense star clusters.
The results of this study, published in Nature Astronomy, provide new evidence for the long-predicted pair-instability mass gap – a “forbidden” mass range for black holes made from stars. While gravitational-wave observations have detected black holes lying within that range, the new analysis suggests that these objects are likely merger-built black holes, not ordinary “first-generation” black holes formed directly from stellar collapse.
The findings highlight how gravitational-wave astronomy is moving beyond simply counting merger events. Observations can now be used to verify new theories, allowing scientists to probe the birth, life, and death of black holes. Such information will help us understand the evolution of stars and clusters in the Universe and challenge current models of stellar evolution. Progress is also expected in nuclear physics, where the mass limit set by pair instability depends on nuclear reactions in the cores of massive stars.
The research was carried out by an international team of scientists led by Cardiff University, with contributions from institutions including Heidelberg University's Center for Astronomy (ZAH) and the STRUCTURES Cluster of Excellence. Cardiff University is one of Britain’s leading research universities, and a member of the Russell group of the UK most-research intensive universities. Heidelberg University is Germany’s oldest university and, as a leading European research institution, member of Germany’s Excellence Strategy.
Further information:
We are pleased to welcome Felix Otto (MPI Leipzig) for the next Mathematical Colloquium on Thursday, 23 April 2026, at 16:15 in the Mathematikon lecture hall. Felix Otto, Director of the MPI in Leipzig and a leading expert in analysis and partial differential equations, will give a talk entitled “Convection-enhanced diffusion, and Brownian motion on the Lie group SLn”.
Abstract:
This talk draws a connection between a well-known phenomenon in fluid dynamics and an object from differential geometry. On the one hand, the ubiquitous phenomenon is that advection by a turbulent divergence-free drift effectively (and dramatically) enhances the diffusion of particles in n-dimensional Euclidean space. On the other hand, the object from differential geometry is a natural notion of Brownian motion on SLₙ, the Lie group and Riemannian manifold of matrices of unit determinant; it is a tensorial version of geometric Brownian motion.The connection is established by tracking the relative position of a pair of particles as a function of their initial configuration and involves a change of time variables: the “time” parameter for the Brownian motion on SLₙ is given by the logarithm of the effective diffusivity of the particles, which increases with physical time.
This is joint work with Peter Morfe and Christian Wagner.
All interested colleagues and students are warmly invited to attend.
Further information:
We are delighted to announce the next event in our Machine Learning Galore! series, focusing on Scientific Machine Learning, which will take place on Wednesday, April 29, from 4:30 to 6:00 pm at INF 205 Mathematikon (5th floor). The event features lab presentations by principal investigators, followed by brief presentations from junior scientists showcasing their latest work. Extended discussions will offer ample opportunity for in-depth exchanges.
Event Details:
- Lab presentations:
- Sascha Diefenbacher
- Lutz Greb
- Christoph Schnörr
- Science Talks:
- Sascha Diefenbacher: Forecasting Generative Amplification
- Andreas Albers (Greb lab): Machine Learning for Molecular Property Prediction: Revisiting Empirical Chemistry with Big Data
- Jonas Cassel (Schnörr lab): Vector Bundle Data Models and Geometric Deep Learning
Registration is free but required via the ML-AI portal:
https://www.mlai.uni-heidelberg.de/en/machine-learning-talks-on-campus
About Scientific Machine Learning:
Scientific Machine Learning is a collaborative initiative by the Interdisciplinary Center for Scientific Computing (IWR) and the STRUCTURES Cluster of Excellence. Its mission is to foster interaction and exchange within the local machine learning community, and to support its development by consolidating activities and resources that might otherwise remain scattered across individual institutions or disciplines. The initiative aligns closely with the objectives of STRUCTURES, which aims to advance fundamental research, and with IWR’s focus on applying machine learning to address long-standing challenges in the natural and life sciences, engineering, and the humanities.
Further information: