var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-4"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-2"><img src="//www2.math.ethz.ch/smsjs/images/arrow_right.png"/></a></div>    <div class="sms_title">      <span style="float: left;">SMS</span>      <span>SWISS MATHEMATICAL SOCIETY</span>      <span style="float: right;">SMG</span>    </div>    <div class="sms_info">      <span style="float: left; width: 250px;">Bulletin no. 12</span>      <span style="float: right; text-align:right; width: 250px;">1.12 - 5.12.2025</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Autumn Semester 2025</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, December 1      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_la"><a class="external" href="https://www.epfl.ch">EPF Lausanne</a></div><div class="event_type"><a class="external" href="https://theory.epfl.ch/seminar/">Theory and Combinatorics Seminar</a></div><br /><div class="event_speaker"> Jiechen Zhang</div><div class="event_title">Prophet Inequalities with Moment Knowledge <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We study a variant of the prophet inequality with limited information, where the decision maker only has access to the first \\(k\\) moments of each random variable, rather than their full distributions. In this work, it is proved that even with full moment knowledge (i.e., \\(k=\\infty\\)), the best possible competitive ratio is \\(\\bigTheta{1/ \\log n}\\), which we show can already be achieved with only knowledge of the first moment.Our result, in particular, implies that to obtain improved prophet inequalities, further assumptions, beyond moment knowledge, are needed. To showcase this direction, we establish improved bounds under additional distributional assumptions, such as MHR, bounded coefficient of variation, or bounded support.</div><div class="event_time">11:00 &bull; EPF Lausanne, INJ114</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/fim/activities/nachdiplom-lectures">Nachdiplomvorlesung</a></div><br /><div class="event_speaker"> Eugenia Malinnikova (Stanford University)</div><div class="event_title">Carleman estimates, unique continuation, and Landis conjecture</div><div class="event_time">13:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/symplectic-geometry-seminar">Symplectic Geometry Seminar</a></div><br /><div class="event_speaker"> Fabio Gironella (Université de Nantes)</div><div class="event_title">Confoliations in high dimensions <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In a pioneering work of 1998, Eliashberg and Thurston proved that, in ambient dimension 3, C^2 foliations can always (besides one example) be C^0-approximated by contact structures in the space of plane fields. To do so, they introduce what they called ``confoliations\'\', that are geometric structures which are mid-way between foliations and contact structures. While these have been studied extensively in dimension 3 by many authors, the situation in higher dimensions is less clear, and there is not even a consensus on what their definition should be. In this talk, I will introduce a new notion of high-dimensional symplectic confoliation, and describe how on one hand it naturally leads to a notion of approximation by contact structures that encompasses all previously known ad-hoc examples, and on the other hand how it also constitute a good class of structures, generalizing contact ones, of which one can study symplectic fillability questions. This is based on work joint with Robert Cardona and on work in progress joint with Seungook Yu.</div><div class="event_time">15:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/mpseminar/seminar.html">Séminaire de Mathématique Physique </a></div><br /><div class="event_speaker"> Alexander  Drewitz  (Universität zu Köln)</div><div class="event_title">Branching Processes and the Fisher–KPP Equation in Spatially Random Environments <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Branching Brownian motion, branching random walks, and the Fisher–KPP equation have been central objects of study in probability theory and mathematical physics over the past decades. Through the Feynman–Kac and McKean representations, the behavior of extremal particles in the branching models is intimately linked to the position of the traveling wave front in the Fisher–KPP equation.In this talk, I will present recent progress on extensions of these classical models to spatially random environments, incorporating random branching rates and random nonlinearities. It turns out that such inhomogeneities give rise to a significantly richer and more delicate phenomenology than in the homogeneous case.</div><div class="event_time">16:15 &bull; Université de Genève, Conseil Général 7-9, Room 1-15</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_be"><a class="external" href="https://www.unibe.ch">Universität Bern</a></div><div class="event_type"><a class="external" href="https://www.math.unibe.ch/research/talks/colloquium/index_eng.html">Mathematisches Kolloquium </a></div><br /><div class="event_speaker">Prof. Dr. Bernhard Krötz (Universität Paderborn)</div><div class="event_title"><a class="external" href="https://www.math.unibe.ch/research/talks/colloquium/index_eng.html">Über Normen auf Harish-Chandra Moduln</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Der Satz von Casselman-Wallach ist ein grundlegendes Resultat in der Theorie der Darstellungen reeller reduktiver Gruppen, das algebraische Darstellungen mit topologischen Darstellungen verbindet. Wir liefern eine quantitative Version dieses Satzes. Dazu führen wir den Begriff der Sobolev-Lücke für einen Harish-Chandra-Modul ein. Dies ist eine neue Invariante, deren Endlichkeit nicht offensichtlich ist. Wir bestimmen die Sobolev-Lücke für Darstellungen im unitären Dual der Gruppe SL(2,R) und beweisen allgemein gleichmäßige Endlichkeitsresultate für Darstellungen der diskreten Reihe und der minimalen Hauptreihe. Wir verwenden diese Begriffe, um klassische Ergebnisse von Bernstein und Reznikov über automorphe Funktionale bezüglich kokompakter Gitter neu zu formulieren und zu erweitern. Insbesondere beweisen wir eine abstrakte Konvexitätsschranke, die für automorphe Funktionale bezüglich allgemeiner Gitter in SL(2, R) gilt und unabhängig vom Typ des unitarisierbaren irreduziblen Harish-Chandra-Moduls ist.Wir berichten über eine gemeinsame Arbeit mit Joseph Bernstein, Pritam Ganguly, Job Kuit und Eitan Sayag. Die Arbeit selbst ist unter https://arxiv.org/pdf/2510.09370 abrufbar. </div><div class="event_time">17:15 &bull; Universität Bern, Sidlerstrasse 5, 3012 Bern, Room B6</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Tuesday, December 2      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/annonces/groupes-geometrie">Groupes et Géométrie </a></div><br /><div class="event_speaker"> Clara  Skowronek  Santos  (Complutense University of Madrid)</div><div class="event_title">Commensurators and Grigorchuk\'s groups <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The abstract commensurator of a group G is a generalization of its group of automorphisms. More concretely, it is a quotient of the set of almost automorphisms of G, that is, the set of isomorphisms between finite index subgroups of G. These commensurators have been studied for certain examples of groups, such as the first Grigorchuk group, and we are currently studying the commensurator of more groups of these family of Grigorchuk\'s groups.C.E.Röver showed that the commensurator of the first Grigorchuk group G is the group generated by the Highman Thompson group G_2,1 and the group G itself. In this talk, I will discuss this commensurator and the one of the Grigorchuk-Erschler group, which can be obtained by similar techniques. I will also present some preliminary results about the automorphism group of a large subfamily of the family of Grigorchuk\'s groups, which we hope will be useful to compute their commensurators. This is ongoing joint work with Alejandra Garrido.</div><div class="event_time">10:30 &bull; Université de Genève, Conseil Général 7-9, Room 1-05</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/fim/activities/nachdiplom-lectures">Nachdiplomvorlesung</a></div><br /><div class="event_speaker"> Eva Miranda (Universitat Politècnica de Catalunya)</div><div class="event_title">Singular Symplectic Manifolds</div><div class="event_time">13:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/annonces/seminaire-danalyse-numerique">Séminaire d\'Analyse Numérique </a></div><br /><div class="event_speaker"> Eugen Bronasco (Chalmers, Gothenburg)</div><div class="event_title">Butcher Series for the Convergence Analysis of Iterative Numerical Integrators: SDC and Parareal <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We present a Butcher series framework for analyzing the convergence of the Spectral Deferred Correction (SDC) and Parareal methods. SDC iteratively improves a low order approximation to achieve high order accuracy, while Parareal introduces parallelism in time by combining coarse and fine propagators. By expressing both algorithms as Runge-Kutta methods whose Butcher tableaus grow with each iteration, we apply classical Butcher series techniques to study their convergence. For SDC, we obtain convergence results under weaker assumptions, explain and exploit the order jump phenomenon, where the observed order of accuracy exceeds theoretical predictions, and design correctors that consistently produce it. For Parareal, we recover and refine known convergence results, offering problem agnostic insights into the structure of iterative time integration algorithms. This talk is based on joint work with Joscha Fregin (TUHH), Ausra Pogozelskyte, Daniel Ruprecht (TUHH), Gilles Vilmart (Univ. of Geneva).</div><div class="event_time">14:00 &bull; Université de Genève, Conseil Général 7-9, Room 1-05</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_dis"><a class="external" href="https://unidistance.ch">UniDistance Suisse</a></div><div class="event_type"><a class="external" href="https://unidistance.ch/en/mathematiques-et-informatique/recherche/number-theory/number-theory-seminar">Number Theory Seminar</a></div><br /><div class="event_speaker"> Dominik Bullack  (ICMAT Madrid)</div><div class="event_title">On Euler systems and Neková&#345;--Selmer complexes <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Euler systems have led to spectacular progress on conjectures concerning the special values of motivic L-series. In recent joint work with David Burns we further develop the axiomatic theory of Euler systems by allowing more general coefficient rings and by systematically incorporating Neková&#345;--Selmer complexes into the framework. I will give an overview of our results, including some concrete arithmetic applications that this refined theory has.</div><div class="event_time">15:00 &bull; <a class="external" href="fernuni.zoom.us/my/davidloeffler">UniDistance Suisse</a></div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/seminaires/lie-sem/">Lie groups and moduli spaces </a></div><br /><div class="event_speaker"> Toyo Taniguchi (Tokyo)</div><div class="event_title">Drinfeld associators and Kashiwara–Vergne associators in higher genera <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A Drinfeld associator is a certain Lie series deeply related to braids on a disk, which is a genus 0 surface. On the other hand, a solution to the Kashiwara–Vergne (KV) problem, originated from Lie theory, corresponds to a solution of the formality problem of the Goldman–Turaev Lie bialgebra associated with a pair-of-pants by the result of Alekseev, Kawazumi, Kuno and Neaf. These objects are first related by Alekseev and Torossian, and Massuyeau constructed an explicit map from the set of Drinfeld associators to the solution set of the KV problem. In this talk, we extend their method to higher genera to obtain a similar map based on Gonzalez’ definition of higher genus Drinfeld associators.</div><div class="event_time">15:00 &bull; Université de Genève, Conseil Général 7-9, Room 1-07</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://uzh.ch">Universit&auml;t Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://www.math.uzh.ch/mat075.1">Zurich Graduate Colloquium</a></div><br /><div class="event_speaker">Abhinaba Mazumder (Universität Zürich)</div><div class="event_title">What are... equivalent codes? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>&lt;span data-olk-copy-source="MessageBody">Cryptography is an essential part of today&apos;s privacy focused world. But how does Cryptography guarantee that your data is indeed &apos;encrypted&apos;? In this talk, we will take a look at how hard mathematical problems give rise to useful cryptographic tools going beyond encryption. We will also delve into what it means for a problem to be called hard, and finally we will look at a particular example (code equivalence), explore its hardness, and see how it&apos;s utilised to give us aforementioned cryptographic tools.&lt;/span>&lt;/p></div><div class="event_time">16:30 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 46</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Wednesday, December 3      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_ba"><a class="external" href="https://unibas.ch">Universität Basel</a></div><div class="event_type"><a class="external" href="https://dmi.unibas.ch/de/studium/mathematik/doktorat/bernoullis-tafelrunde">Bernoullis Tafelrunde</a></div><br /><div class="event_speaker"> Flavio Dalessi (Basel)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/studium/mathematik/doktorat/bernoullis-tafelrunde/detail/bernoullis-tafelrunde-flavio-dalessi-basel/">Branching Random Walk in Random Environment</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />One approach to modeling population growth in a heterogeneous environment is through a branching random walk with inhomogeneous branching rates. In this talk, we introduce the branching random walk in a spatially random branching environment and discuss its known properties. We then turn to the behavior of its maximal displacement, for which a functional central limit theorem has been established. Finally, we discuss recent progress on proving the tightness of the maximal displacement around its median. pdf_version</div><div class="event_time">12:15 &bull; Universität Basel, Seminarraum 05.001</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/algebraic-geometry-and-moduli-seminar">Algebraic Geometry and Moduli Seminar</a></div><br /><div class="event_speaker">Prof. Dr. Dan Petersen (Stockholm University)</div><div class="event_title">Moments in families of L-functions over function fields via homological stability of moduli spaces <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />This is a report of joint work with Bergström-Diaconu-Westerland and Miller-Patzt-Randal-Williams. There is a "recipe" due to Conrey-Farmer-Keating-Rubinstein-Snaith which allows for precise predictions for the asymptotics of moments of many different families of L-functions. Our work concerns the CFKRS predictions in the case of the quadratic family over function fields, i.e. the family of all L-functions attached to hyperelliptic curves over some fixed finite field. One can relate this problem to understanding the homology of the moduli space of hyperelliptic curves with symplectic coefficients. With Bergström-Diaconu-Westerland we compute the stable homology groups of the moduli space of hyperelliptic curves with these coefficients, together with their structure as Galois representations. We moreover show that the answer matches the number-theoretic predictions. With Miller-Patzt-Randal-Williams we prove a uniform range for homological stability with these coefficients. Together, these results imply the CFKRS predictions for all moments in the function field case, for all sufficiently large (but fixed) q.</div><div class="event_time">13:30 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/geometry-seminar">Geometry Seminar</a></div><br /><div class="event_speaker"> Stéphane Lamy (Toulouse)</div><div class="event_title">Polynomial automorphisms and negative curvature <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Polynomial or birational transformations of &#8450;<sup>n</sup> form huge groups as soon as n > 1, and the following basic questions are open in general:&lt;ul>  &lt;li>Do they admit normal subgroups (apart from the obvious subgroup of Jacobian 1 automorphisms in the polynomial case)?  &lt;/li>  &lt;li>Do they satisfy a Tits alternative, as in the linear case?&lt;/li>  &lt;li>Is any finite subgroup conjugate to a subgroup of GL(n)?&lt;/li>&lt;/ul>After explaining the context, I will discuss some particular cases in dimensions 3 and 4 where we can answer these questions, using some actions on some metric spaces with negative curvature. (based on several joint works with P. Przytycki)</div><div class="event_time">15:30 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/seminar-on-stochastic-processes">Seminar on Stochastic Processes</a></div><br /><div class="event_speaker">Dr. Joffrey Mathien (Aix-Marseille Université (AMU))</div><div class="event_title">Cutoff for geodesic path and Brownian motion on hyperbolic manifolds <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />For an ergodic dynamical system, the cutoff describes an abrupt transition to equilibrium. Historically introduced in seminal work by Diaconis, Shahshahani and Aldous for card shuffling and other random walks on finite groups, there are now numerous examples of Markov chains and Markov processes where the cutoff has been established.Most of the current examples are on finite spaces. In this talk, we study cutoff for classical processes -- namely Brownian motion and geodesic paths -- on compact hyperbolic manifolds, and we develop a spectral strategy introduced by Lubetzky and Peres in 2016 for Ramanujan graphs and further developed in different geometric contexts. In particular, we extend results obtained by Golubev and Kamber in 2019 to any dimension and still are able to obtain cutoff under weaker hypothesis.Joint work with C. Bordenave</div><div class="event_time">17:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Thursday, December 4      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/fim/activities/nachdiplom-lectures">Nachdiplomvorlesung</a></div><br /><div class="event_speaker"> Bo\'az Klartag (The Weizmann Institute of Science)</div><div class="event_title">Isoperimetric inequalities in high-dimensional convex sets</div><div class="event_time">10:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_la"><a class="external" href="https://www.epfl.ch">EPF Lausanne</a></div><div class="event_type"><a class="external" href="https://theory.epfl.ch/seminar/">Theory and Combinatorics Seminar</a></div><br /><div class="event_speaker"> Paul Dütting</div><div class="event_title">Nearly Tight Regret Bounds for Profit Maximization in Bilateral Trade <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Bilateral trade models the task of intermediating between two strategic agents, a seller and a buyer, willing to trade a good for which they hold private valuations. We study this problem from the perspective of a broker, in a regret minimization framework. At each time step, a new seller and buyer arrive, and the broker has to propose a mechanism that is incentive-compatible and individually rational, with the goal of maximizing profit.We propose a learning algorithm that guarantees a nearly tight $\\tilde{O}(\\sqrt{T})$ regret in the stochastic setting when seller and buyer valuations are drawn i.i.d. from a fixed and possibly correlated unknown distribution. We further show that it is impossible to achieve sublinear regret in the non-stationary scenario where valuations are generated upfront by an adversary. Our ambitious benchmark for these results is the best incentive-compatible and individually rational mechanism. This separates us from previous works on efficiency maximization in bilateral trade, where the benchmark is a single number: the best fixed price in hindsight.A particular challenge we face is that uniform convergence for all mechanisms\' profits is impossible. We overcome this difficulty via a careful chaining analysis that proves convergence for a provably near-optimal mechanism at (essentially) optimal rate. We further showcase the broader applicability of our techniques by providing nearly optimal results for the joint ads problem.Preprint available from on arXiv (https://arxiv.org/abs/2509.22563).Forthcoming in FOCS 2025.Joint work with Simone di Gregorio (Sapienza), Federico Fusco (Sapienza), Chris Schwiegelshohn (Aarhus).<b>Short bio: </b>Paul Dütting is a Staff Research Scientist at Google Switzerland whose research focuses on the intersection of Algorithms and Economics. He was previously an Associate Professor of Mathematics at the London School of Economics (LSE), where he now holds a visiting faculty role. He received several awards for his work, including two Best Paper Awards at the ACM Conference on Economics and Computation and a Best Paper Award at the ACM The Web Conference.</div><div class="event_time">11:00 &bull; EPF Lausanne, BC 420</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ba"><a class="external" href="https://unibas.ch">Universität Basel</a></div><div class="event_type"><a class="external" href="https://dmi.unibas.ch/de/forschung/mathematik/zahlentheorie/">Seminar Zahlentheorie</a></div><br /><div class="event_speaker"> Jerson Caro (Boston University)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/number-theory-seminar-jerson-caro-boston-university/">Title T.B.A.</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Title: Counting and Finding Rational Points on Surfaces Abstract: A celebrated result of Coleman gives an explicit version of Chabauty\'s theorem, bounding the number of rational points on curves over number fields via the study of zeros of p-adic analytic functions. While many developments have extended and refined this result, obtaining analogous explicit bounds for higher-dimensional subvarieties of abelian varieties remains a major challenge. In this talk, I will sketch the proof of such an explicit bound for surfaces contained in abelian varieties -- a step toward a higher-dimensional Chabauty-Coleman method. This is joint work with Héctor Pastén. I will also describe an application of this method to a computational problem: determining an upper bound for the number of unexpected quadratic points on hyperelliptic curves of genus 3 defined over Q. I will illustrate the method through an explicit example where this set can be computed. This is joint work with Jennifer Balakrishnan.</div><div class="event_time">14:15 &bull; Universität Basel</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_la"><a class="external" href="https://www.epfl.ch">EPFL Lausanne</a></div><div class="event_type"><a class="external" href="https://www.epfl.ch/labs/hessbellwald-lab/seminar/epfl-topology-seminar-fall-2024/">Séminaire de Topologie </a></div><br /><div class="event_speaker"> Hugo Moeneclaey (University of Gothenburg)</div><div class="event_title">Synthetic Stone Duality: A Synthetic Approach to Condensed Mathematics <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Synthetic Stone duality is an extension of Homotopy Type Theory (HoTT) by 5 well-chosen axioms. These axioms are validated by the interpretation of HoTT in the higher topos of light condensed anima. Therefore, any results we prove in synthetic Stone duality can be interpreted as a result about light condensed anima.First, we will explain the general concept of synthetic mathematics, with an emphasis on geometry, HoTT, higher topoi and cohomology. Then we will present the 5 axioms of Synthetic Stone duality and give detailed proofs of some of their elementary consequences, to give a feeling of how it is to work with them. We will then give an overview of our synthetic version of Theorem 3.2 from Peter Scholze Lecture Notes on condensed mathematics (itself adapted from Roy Dyckhoff). Our version states that the cohomology of a compact Hausdorff space with countably presented coefficients can be computed from a cover of X by a Stone space.If time permits, we will sketch applications of this result to the shape modality, which gives a convenient interface between topological spaces and their homotopy types.</div><div class="event_time">16:00 &bull; <a class="external" href="https://plan.epfl.ch/?room==CM%201%20517">EPFL Lausanne, Mathematics</a></div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/annonces/groupes-geometrie">Groupes et Géométrie </a></div><br /><div class="event_speaker"> Dominik  Francoeur  (Madrid)</div><div class="event_title">Intersection-saturated groups and groups with micro-supported actions <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A group is said to possess the Howson property if the intersection of any two finitely generated subgroups is again finitely generated. When a group fails to have the Howson property, one can try to characterise how far it is from having it. Such considerations give rise to the notion of intersection-saturated groups, introduced recently by Delgado, Roy and Ventura. In this talk, we\'ll see a new construction for intersection-saturated groups, based on so-called micro-supported actions, that allows one in particular to produce finitely presented amenable examples.</div><div class="event_time">16:15 &bull; Université de Genève, Conseil Général 7-9, Room 1-05</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://www.math.uzh.ch/mat675.1">PDE and Mathematical Physics</a></div><br /><div class="event_speaker">Prof. Dr. Lukas Koch</div><div class="event_title">Uniform Lipschitz estimates for regularised optimal transport <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>&lt;span style="caret-color: #000000; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">I will discuss how to obtain Lipschitz estimates for regularised optimal transport problems using a variational approach. In particular, this&nbsp;&lt;/span>&lt;br style="caret-color: #000000; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">&lt;span style="caret-color: #000000; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">gives Lipschitz regularity for entropic optimal transport independent of the regularisation parameter. A crucial step in the approach are local&nbsp;&lt;/span>&lt;br style="caret-color: #000000; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">&lt;span style="caret-color: #000000; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">L^\\infty-estimates, which are of independent interest. The talk is based on joint work with Rishabh Gvalani (ETH).&lt;/span>&lt;/p></div><div class="event_time">16:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 19.2</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://www.math.ethz.ch/mathematik-und-ausbildung/weiterbildung/kolloquium.html">Kolloquium über Mathematik, Informatik und Unterricht</a></div><br /><div class="event_speaker"> Guido Lob (Liceo cantonale di Locarno)</div><div class="event_title">Die Mathematik als Hilfsmittel des Taschenrechners <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Der Taschenrechner ist ein Wunderwerk: In wenigen Augenblicken erwacht ein Plastikrechteck zum Leben und kann uns Werte für Wurzeln, Logarithmen, Trigonometrischen Funktionen und vieles weiteres liefern.Was verbirgt sich hinter diesem scheinbar einfachen, aber so mächtigen Gerät? Es sind nicht nur Taylor-Polynome: Es gibt viele weitere mathematische Eigenschaften und Überlegungen, die in seinem Inneren genutzt werden, um die gewünschten Ergebnisse auf effiziente und elegante Weise zu erzielen.<br /><br /><a href="https://math.ethz.ch/content/dam/ethz/special-interest/math/math-ausbildung-dam/documents/kolloquium/Vortrag_GLOB.pdf">Präsentation</a><br /></div><div class="event_time">17:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 19.1</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/la-une/maths-partag-2024">Maths à PartaG</a></div><br /><div class="event_speaker"> Etienne  Ghys (ENS Lyon)</div><div class="event_title">Les merveilles de la géométrie des lettres de l’alphabet <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Pendant des siècles, les copistes écrivaient des livres à la main. En 1455 Gutenberg a tout bousculé et on a commencé à fondre des caractères en plomb. Avant de les fondre, il fallait les dessiner. Les graveurs les plus célèbres de la Renaissance ont modifié la forme des lettres pour qu’elles soient lisibles et jolies. Ils ont utilisé les outils dont ils disposaient : des règles et des compas. Il y a quarante ans, tout a basculé avec l’explosion de l’informatique. Comment dessiner les caractères d’imprimerie en respectant le magnifique travail des artistes de la Renaissance ? Cet exposé sera un très rapide survol de l’histoire de la typographie vue par un géomètre.</div><div class="event_time">18:30 &bull; Université de Genève, Uni Dufour, U300</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Friday, December 5      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_ba"><a class="external" href="https://unibas.ch">Universität Basel</a></div><div class="event_type"><a class="external" href="https://dmi.unibas.ch/de/forschung/mathematik/seminar-in-numerical-analysis">Seminar in Numerical Analysis</a></div><br /><div class="event_speaker"> Mamadou N\'diaye (Université Polytechnique Hauts-de-France)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/seminar-in-numerical-analysis-mamadou-ndiaye-universite-polytechnique-hauts-de-france/">High-order explicit time integration for the simulation of seismic wave propagation on GPU-CPU systems</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In this presentation, we address the numerical solution of the second-order acoustic wave equation using high-order explicit time-integration methods on CPU-GPU architectures. After discretizing the spatial domain with spectral element method, we compare several time-integration schemes for the resulting system of ODEs. We first consider the classical second-order leapfrog method, followed by higher-order Runge-Kutta-Nyström (RKN) schemes and the modified equation approach. We then focus on the analysis of the stability properties of the RKN method. Strategies for incorporating the damping term, which involves the first-order time derivative, are discussed with particular attention to preserving the order of convergence of the schemes. The proposed approaches are compared in terms of computational efficiency, and 3D numerical simulation for the acoustic wave equation are presented. For further information about the seminar, please visit this webpage .</div><div class="event_time">11:00 &bull; Universität Basel, Room 05.001, Spiegelgasse 5, 4051 Basel</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_la"><a class="external" href="https://www.epfl.ch">EPF Lausanne</a></div><div class="event_type"><a class="external" href="https://www.epfl.ch/labs/anmath/seminars/">Seminar of Analysis </a></div><br /><div class="event_speaker"> Guillaume  Carlier (Paris-Dauphine)</div><div class="event_title">Quantitative stability of push-forwards by optimal maps <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In this talk, based on a joint work with Quentin Mérigot and Alex Delalande, I will discuss (sharp)quantitative stability of push-forwards by optimal transport maps. The main step of the proofrelies on a new bound (of independent interest) that quantifies the size of the singular set ofconvex functions in terms of covering numbers.</div><div class="event_time">14:15 &bull; EPF Lausanne, MA B1 11</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/algebraic-geometry-and-moduli-seminar">Algebraic Geometry and Moduli Seminar</a></div><br /><div class="event_speaker">Dr. Denis Nesterov (ETH Zürich)</div><div class="event_title">Unramified maps to abelian varieties <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Spaces of unramified maps are a higher-dimensional generalization of spaces of admissible covers, introduced by Kim, Kresch, and Oh. I will discuss unramified maps to abelian varieties and how they can be used to compute cycles associated with spaces of stable maps. Joint work with Jeremy Feusiand Aitor Iribar López.</div><div class="event_time">16:00 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>      </div>    </div>  </div>  <div id="sms_footer">    address: Alessandra Naldi Windler, Departement Mathematik, HG G 51.4, ETH Zurich, Raemistrasse 101, CH-8092 Zurich<br />    email: <a href="mailto:bulletin@math.ch">bulletin@math.ch</a> | phone: +41 44 632 3684 | url: <a href="https://math.ch">https://math.ch</a>    <br /><br /><img src="//www2.math.ethz.ch/smsjs/sms_logo.gif" width="150" alt="SMS/SMG Logo" title="SMS/SMG Logo" />  </div></div>';