Tessera

STRUCTURES Cluster of Excellence Heidelberg

@structures-hd.bsky.social

A unifying approach to emergent phenomena in the physical world, mathematics, and complex data. Website: https://structures.uni-heidelberg.de/ Blog: https://structures.uni-heidelberg.de/blog (Impressum: https://www.uni-heidelberg.de/de/impressum)

250 Posts228 Follower 80 Folgt

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 6d ago

Our YRC member Ricardo took part in the 16th International LISA Symposium, held from 21 to 26 June 2026 at the University of Maryland in College Park, USA. (1/5) #YRC #STRUCTURESHeidelberg #LISASymposium2026 #GravitationalWaves #Astrophysics #EarlyCareerResearchers #HeidelbergUniversity

During the conference, Ricardo gave a talk and participated in a “state of the profession” session on Equity, Diversity, and Inclusion. His visit also connected to the history of gravitational-wave research. The University of Maryland campus is home to the Weber bars, early attempts to build detectors for gravitational waves that were ultimately unsuccessful. Thanks to the support from STRUCTURES, Ricardo was able to attend the symposium, present his work, and engage with the international scientific community!

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 7d ago

From 15 to 19 June 2026, several members of the STRUCTURES community, including Paola Vaccaro, Michela Mapelli, Lumen Boco, Cecilia Sgalletta and Lucas De Sa, took part in the XVI Einstein Telescope Symposium at RWTH Aachen University in Aachen, Germany. (1/5)

The programme included presentations on current progress and future plans for the Einstein Telescope, as well as opportunities for scientific exchange and networking. An Early Career Researchers Meeting also provided a dedicated space for exchange among early-career scientists. Events such as this allow members of STRUCTURES to engage with international research networks and contribute to ongoing discussions on the future of gravitational-wave astronomy.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · last wk.

There's a beautiful complex geometrical structure behind machine learning – the new STRUCTURES Blog post by Yara Elshiaty shares this story. Come and read to learn more! structures.uni-heidelberg.de/preview_blog... #MachineLearning #Data #Geometry

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2w ago

Join us tomorrow for an afternoon of research presentations, discussion and exchange, followed by the STRUCTURES summer party! Looking forward to seeing you there! #UniHeidelberg #STRUCTURESHeidelberg #StructuresYRC

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2w ago

🚨 Reminder: Registration for the #SchöntalWorkshop 2026 closes soon! Join us for #interdisciplinary exchange & inspiring discussions in the unique setting of Schöntal Abbey. 🔗 Register here: tally.so/r/D4byjb Participation free of charge for YRC members! #structuresheidelberg #uniheidelberg

Reminder: 10th Schöntal Workshop: Dynamical Systems. 25th to 28th of August 2026, Schöntal Abbey. Are you an MSc, PhD student or early-career Postdoc? Join us for inspiring discussions and interdisciplinary exchange in the unique atmosphere of Schöntal Abbey. Please register by end of this week! Registration form: link in bio. Participation free of charge for members of the STRUCTURES YRC.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3w ago

Reminder: STRUCTURES Jour-Fixe is today! Olivier Pierre-Louis (Uni. of Lyon) will give a talk about “The Allen-Cahn equation with multiplicative oscillatory driving”. 📅 Today, July 17 🕐 Pretalk: 13:00 🕜 Main talk: 13:30 📍 Phil 12, gHS Abstract & Info: structures.uni-heidelberg.de/news/files/2...

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3w ago

How can a machine predict if two images have the same object? How is it that it tells apart different people? The answer lies in geometry! Our latest blog post by Yara Elshiaty relates this amazing process: structures.uni-heidelberg.de/blog/posts/2... #Riemannian #metric #ML #STRUCTURES

STRUCTURES Blog | The Geometry Hidden in Data: An Introduction to Riemannian Metric Learning

Blog of the STRUCTURES Cluster of Excellence. On this blog we show pictures of interesting structures related to our research in the STRUCTURES Cluster, and we give you an idea what they are, how they...

structures.uni-heidelberg.de

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3w ago

Join this week’s STRUCTURES Jour Fixe with Olivier Pierre-Louis (University of Lyon) on “The Allen-Cahn equation with multiplicative oscillatory driving”. 📅 Friday, July 17 🕐 Pretalk: 13:00 🕜 Main talk: 13:30 📍 Phil 12, gHS Full abstract & info: structures.uni-heidelberg.de/news/files/2...

We are pleased to welcome Olivier Pierre-Louis (University of Lyon) to this week's Jour-Fixe for a talk entitled: “The Allen-Cahn equation with multiplicative oscillatory driving”. The talk will focus on the Allen-Cahn equation, a widely used model for systems in which domains form and grow over time. It will discuss how this behaviour changes under oscillatory multiplicative driving, which represents, for example, an oscillation of the temperature in an Ising system that may or may not cross the critical temperature. The main talk will be preceded by a pretalk, also by Olivier Pierre-Louis, at 13:00. Everyone interested is warmly invited to join. There will be coffee, tea & snacks before and after the event. You are more then welcome to meet and discuss up-to-date topics with participants or ask questions to the lecturer! For those unable to attend in person, online participation is available via Zoom: Meeting ID: 935 6549 3662 | Code: 928036

Abstract: The Allen–Cahn equation, also known as the Time-Dependent Ginzburg–Landau equation or Model A, is one of the most generic models for describing systems where domains form. It has been widely used in phase transitions (such as spinodal decomposition), but also in many non-equilibrium systems and other applications like image segmentation and denoising. One of the most salient features of the Allen–Cahn equation is the coarsening process, by which domains grow over time. This process results from the motion and interaction of interfaces between domains. We will first review some properties of the Allen–Cahn equation in one and two dimensions and present two related length scales that describe the structures emerging from its dynamics in both the linear and nonlinear regimes. Then, we will examine how the behavior of the Allen–Cahn equation is affected by an oscillatory multiplicative driving, which represents, for example, an oscillation of the temperature in an Ising system that may or may not cross the critical temperature. These oscillations lead to a novel regime in one dimension with accelerated coarsening when the oscillations cross the critical value. In contrast, we will see that in two dimensions, the coarsening is not affected by such oscillations. However, oscillations can lead to merging of interfaces or to stronger deviations from the usual motion by curvature in two dimensions.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 4w ago

We are delighted to announce this year's YRC Schöntal Discussion Workshop on "Dynamical Systems"! 25–28 Aug · Schöntal Abbey Registration deadline: 24 July Workshop details and registration: structures.uni-heidelberg.de/news.php?sho...

We are delighted to announce this year's YRC Schöntal Discussion Workshop on Dynamical Systems, which will take place from the 25th to the 28th of August at the quaint and charming Schöntal Abbey. The aim of the workshop is to provide an opportunity for early-career scientists to gather and discuss topics that go beyond the standard mathematics and physics curriculum, and to approach different subjects from their respective fields of research. The goal is to encourage interdisciplinary scientific exchange between the various areas of the STRUCTURES Cluster. This year, the overarching topic of Dynamical Systems will be the protagonist. As a key concept in many physical, mathematical, computational and biological applications, we expect it to foster collaboration across different fields and spark conversations that may lead to innovative and creative ideas and applications.

The workshop will guide participants through the fundamentals of dynamical systems, including the distinction between continuous and discrete time systems, core concepts such as stability, chaos, and bifurcation theories, and modern applications ranging from training algorithms to recurrent neural networks (RNNs). This year's invited experts are Dr. Zahra Monfared and Prof. Dr. Tim Laux. Organizing team:
The workshop is organized by Alicia Castro, Alessandro Di Gregorio, Sander Hummerich, Luis Walter. About the Young Researchers Convent (YRC): This workshop is funded by STRUCTURES Young Researchers Convent (YRC), a subgroup of the STRUCTURES Cluster of Excellence dedicated to supporting early-career scientists. The YRC strives to help its members realize their own projects, and if you think your work fits within the concept of STRUCTURES, you are welcome to apply for YRC membership. If your supervisor is a STRUCTURES member, you are directly eligible. Registration deadline: 24 July 2026.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 4w ago

We are pleased to share our July newsletter, with research news on modified gravity, future events, and community insights. Read and enjoy! structures.uni-heidelberg.de/news/files/2... #blackholes #gravastar #schöntal

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · last mo.

We congratulate our member Fred Hamprecht, head of the Scientific AI group at the Interdisciplinary Center for Scientific Computing (IWR, on securing one of the European Research Council's prestigious ERC Advanced Grants! 🎉 (1/4) #STRUCTURESHeidelberg #EuropeanResearchCouncil #AI #uniheidelberg

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · last mo.

What happens when mathematicians and space engineers meet? Geometry Space Surrey brought together researchers from 8 countries to explore how symplectic geometry can inform space mission design. Full article available here: structures.uni-heidelberg.de/news.php?sho...

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

Can the pretrained correlations learned by Large Language Models (LLMs) be useful for physics? This question was at the heart of today's #STRUCTURESJourFixe by Caroline Heneka. Many thanks for the engaging presentation & insightful discussions, as well as to Daniel Schiller for the pre-talk 👏.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

🎉 Don’t forget today’s STRUCTURES Jour Fixe on LLMs and their possible applications in physics! Caroline Heneka (ITP) speaks at 13:30, preceded by a pretalk by Daniel Schiller at 13:00. 📍 Phil 12 gHS ☕ Coffee, tea & snacks Abstract & Info: structures.uni-heidelberg.de/news/files/2...

Don’t forget today’s STRUCTURES Jour Fixe on Large Language Models and their possible applications in physics! We are pleased to welcome Caroline Heneka (ITP, Heidelberg University) for her talk: “Large Language Models – are pretrained language correlations useful for physics?” The main talk will be preceded by a pretalk by Daniel Schiller. Everyone interested is warmly invited to join us, meet other participants and take part in the discussion!

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

Can LLMs help us understand the Universe? This Friday at 13:30, Caroline Heneka (ITP) will give a talk on "Large Language Models are pretrained language correlations useful for physics? 🕐 Pretalk by Daniel Schiller: 13:00 Full abstract & info: structures.uni-heidelberg.de/news/files/2...

Can AI in the form of Large Language Models (LLMs) inform physics and help us understand the Universe? We are pleased to welcome Caroline Heneka (ITP, Heidelberg University) for a talk entitled: “Large Language Models – are pretrained language correlations useful for physics?” The talk explores how LLMs can be used to analyze and generate 3D maps of the cosmological large-scale structure, with a particular focus on 21cm data of neutral hydrogen for the Square Kilometre Array (SKA). As such, these new AI methods may also benefit fundamental physic research. The main talk will be preceded by a pretalk by Daniel Schiller at 13:00. Everyone interested is warmly invited to join. There will be coffee, tea & snacks before and after the event. You are welcome to meet and discuss up-to-date topics with participants or ask questions to the lecturer!

Abstract: For many fundamental physics applications, transformers, as the state of the art in learning complex correlations, benefit from pretraining on quasi-out-of-domain data. The obvious question is whether we can exploit Large Language Models, requiring proper out-of-domain transfer learning. We show how LLMs can be used to analyze and generate 3D maps of the cosmological large-scale structure for a large part of the observable Universe, in particular 21cm data of neutral hydrogen for the Square Kilometre Array (SKA). We combine a LLM with connector networks and show, for cosmological parameter regression and lightcone generation, that this Lightcone LLM (L3M) outperforms standard initialization and compares favorably with dedicated networks of matching size.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

🎉 We congratulate our member Michela Mapelli on having 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. structures.uni-heidelberg.de/news.php?sho...

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

structures.uni-heidelberg.de

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

Convex hulls, phase diagrams, and plenty of interesting discussion. Thanks to Prof. Kees Dullemond for an engaging STRUCTURES Jour Fixe talk last Friday, showing how geometry can illuminate thermodynamics 👏. (1/2) #STRUCTURESHeidelberg #StructuresJourFixe #InterdisciplinaryScience #UniHeidelberg

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

Reminder: STRUCTURES Jour Fixe is happening today! 🎉 Today, Cornelis Dullemond (ZAH, Heidelberg) will talk about "Computing phase diagrams using a convex hull algorithm" 📅 Today, 5 June 2026, 13:30 📍 Phil12 + Online #STRUCTURES #HeidelbergUniversity #JourFixe #ResearchTalk

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

What if a complex physics problem could be solved with a simple geometric idea? At this STRUCTURES Jour Fixe, Cornelis Dullemond will present a convex hull approach to compute phase diagrams in physics, materials science and geoscience. 📅 5 June, 13:30 📍 Phil12 gHS + online #STRUCTURES #JourFixe

What if a notoriously complicated physics problem could be solved with a simple geometric idea? Phase diagrams are everywhere in physics, materials science and geoscience. Yet the standard methods to compute them can be surprisingly cumbersome. In this STRUCTURES Jour Fixe, Cornelis Dullemond (ZAH, Heidelberg) will show a simple but mostly overlooked convex hull approach to compute these diagrams efficiently and elegantly. Join us this Friday to learn more. 5 June 2026, 13:30. Phil12 Large Lecture Hall + Online

Phase diagrams are ubiquitous in physics. Usually they are plotted as a function of ambient conditions, for instance as a function of T (temperature) and P (pressure). In geophysics (rocks and magmas) it is also important to make phase diagrams as a function of composition, typically denoted by Xi. For typical compositions found in Nature, at a given T and P, multiple phases usually co-exist in equilibrium with each other. The compositional phase diagrams can become complex, and computing these diagrams them using the textbook mathematical methods can be cumbersome. However, there is a very simple, but mostly overlooked, computational approach based on the convex hull of a set of phase points, to compute these diagrams efficiently and elegantly. The results from the method not only give the phases at all points in the diagram, but more importantly, they give the geometry and topology of the diagram. This allows the user to gain deep insight in the reason why certain phases are stable and others are not. In this talk I will explain the problem and the method, and I will show example results.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

STRUCTURES YRC members Manuel Klockow and Peter Lippmann presented their work at ICLR 2026 in Rio de Janeiro, Brazil. (1/5) #STRUCTURESHeidelberg #ICLR2026 #MachineLearning #DeepLearning #GraphNeuralNetworks #earlycareerResearcher#HeidelbergUniversity #ScientificMachineLearning

STRUCTURES YRC members Manuel Klockow and Peter Lippmann presented their work “A Function-Centric Graph Neural Network Approach for Predicting Electron Densities” at the 14th International Conference on Learning Representations (ICLR) in Rio de Janeiro, Brazil. Their study introduces a graph neural network-based method, which is currently the most accurate known ML approach for electron density prediction on highly competitive benchmarks. We are pleased to see research supported by STRUCTURES represented at ICLR, one of the leading international conferences in machine learning and representation learning. Congratulations to Manuel Klockow, Peter Lippmann, and all collaborators involved. The International Conference on Learning Representations (ICLR) is one of the leading international conferences in artificial intelligence, with a particular focus on representation learning and deep learning. It brings together researchers from academia and industry to present cutting-edge work across machine learning, data science, and application areas such as computer vision, computational biology, natural language processing, robotics, and reinforcement learning.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 2mo ago

🌌 Exciting new results from gravitational-wave astronomy – including evidence for so-called second-generation black holes, with contributions from STRUCTURES professor Michela Mapelli (@micmap.bsky.social) @uniheidelberg.bsky.social #Science #GravitationalWaves #BlackHoles (1/2)

EGO and the Virgo Collaboration@egovirgo.bsky.social · 2mo ago

The @ligo.org – Virgo – KAGRA Collaboration published today a new catalog of gravitational wave events that adds 161 events to the collection, bringing the total number of gravitational wave signals detected to date to 390 🤯

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

🚨 Reminder: STRUCTURES Jour Fixe is today! 🎉 Sebastian Stapelberg will share news and updates from the STRUCTURES Office. This is a great opportunity to catch up and stay informed! 📅 May 22, 13:30 📍 Phil 12 gHS & online ☕ Free coffee, tea & snacks Everyone welcome! #STRUCTURES #JourFixe

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

STRUCTURES Jour Fixe this Friday! Sebastian Stapelberg will share news and updates from the STRUCTURES Office! 📅 May 22, 13:30 📍 Phil 12 gHS & online ☕ Free coffee, tea & snacks Everyone welcome! #STRUCTURES #JourFixe #HeidelbergUniversity #AcademicEvents #ResearchCommunity

STRUCTURES Jour Fixe this Friday! Sebastian Stapelberg will share news from the STRUCTURES Office and updates from the past months. May 22, 13:30. Phil 12 gHS & online. Free coffee, tea & snacks. Everyone welcome!

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

You want to participate in a conference or take an online course but don't know how to finance it? You need to buy equipment for your project? You are looking for a book you can't find in the university library? The #STRUCTURES YRC is here to support... (1/5) #EarlyCareer #Funding #Heidelberg

Promotional poster for the “STRUCTURES Cluster of Excellence – YRC Funding Call, May 2026.” The image shows a globe with flight paths and location markers, symbolizing international research opportunities and travel funding. Below the globe are icons representing travel funds, books, online courses, and tablets. The background features the Heidelberg cityscape with a bridge and hills at sunset. At the bottom, a yellow “Apply Now!” button appears next to the application deadline: 17 May 2026.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

The biggest #blackholes in the Universe may not be born from collapsing stars. A new study involving our member Michela Mapelli (@micmap.bsky.social) & collaborators suggests they form through violent mergers in dense star clusters: structures.uni-heidelberg.de/news.php?sho... #science #astronomy

Biggest Black Holes From Violent Merging Events in Star Clusters

The biggest black holes in the Universe may not be born from collapsing stars. A new study involving STRUCTURES scientist Michela Mapelli and collaborators at

structures.uni-heidelberg.de

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

‼️ Don't miss today's first talk after the semester break! Join us today at 13:00 for a pretalk with Matthias Bartelmann and at 13:30 for a talk with Ullrich Köthe on "EOFlows"! 📍Phil 12 gHS ☕ Coffee & snacks in Room 106 Detail & Abstract: structures.uni-heidelberg.de/news/files/2...

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

The STRUCTURES Jour Fixe is back! 🎉 This Friday, Ullrich Köthe talks about “EOFlows — a non-linear generalization of PCA.” 📅 May 08, 13:30 🕐 Pretalk: 13:00 📍 Phil 12 gHS & online Everyone welcome! Abstract & Info: structures.uni-heidelberg.de/news/files/2... #STRUCTURES #JourFixe

The STRUCTURES Jour Fixe is finally back after the semester break! We are excited to welcome everyone again this Friday for a talk by Ullrich Köthe (IWR, Universität Heidelberg) on “EOFlows — a non-linear generalization of PCA” and a pretalk from Armand Roussellot. The main talk will introduce Entropy-Ordered Flows as a non-linear generalization of Principal Component Analysis, with a focus on interpretability in machine learning approaches and possible future applications in physics. Friday, May 08, 2026. Pretalk by Armand Rousselot at 13:00. Main talk at 13:30. Philosophenweg 12, gHS. Zoom: Meeting ID 935 6549 3662 | Code: 928036. Free coffee, tea & snacks in Room 106. Everyone interested is warmly invited to join us! We look forward to seeing many of you again and starting the Jour Fixe after the break together.

Principal Component Analysis (PCA) is a standard tool to identify the important factors of variation of a dataset in an unsupervised manner. From a machine learning perspective, PCA can be interpreted as an encoder-decoder pair restricted to linear transformations. Normalizing flows (NF) are a natural non-linear generalization of encoder-decoder architectures, but lack the interpretability of PCA.

Entropy-ordered flows (EOFlows) overcome this limitation by using orthogonality regularization during NF training, such that the converged decoder induces an approximately orthogonal curvilinear coordinate system that is aligned with the data geometry. As a result, each latent dimension has a distinct semantic effect, and different dimensions can be sorted by importance according to their "explained entropy", analogous to "explained variance" in PCA. We show how EOFlows are trained, what factors they find on the portrait dataset CelebA, and how stable their outputs are under repeated training and in comparison to existing methods. Ideally, the colloquium would identify promising EOFlow applications in physics to pursue in the future.

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 3mo ago

The Scientific Software Center (SSC) of Heidelberg University offers a variety of scheduled and on demand courses connected to research software development. These courses are open to all students, PhD students, postdocs, and researchers. Have a look at the programme: www.ssc.uni-heidelberg.de/en

STRUCTURES Cluster of Excellence Heidelberg @structures-hd.bsky.social · 4mo ago

Have you read about the intriguing advances dynamical systems theory brings to forecasting agents? If not, don't miss these developments and take a look at our blog post by Daniel Durstewitz & Christoph Hemmer: structures.uni-heidelberg.de/blog/posts/2...! #AI #DynamicalSystems #TSFM