var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-21"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-19"><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. 4</span>      <span style="float: right; text-align:right; width: 250px;">9.3 - 13.3.2026</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Spring Semester 2026</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, March 9      </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/s/symplectic-geometry-seminar">Symplectic Geometry Seminar</a></div><br /><div class="event_speaker"> Joshua Sabloff (Haverford College)</div><div class="event_title">Weak Relative Calabi-Yau Structures for Legendrian Contact Homology <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The Legendrian Contact Homology (LCH) differential graded algebra (DGA) was among the first, and is still among the most important, non-classical invariants of Legendrian knots. In this talk, I will tell a story that builds up ever more sophisticated analogues of Poincare Duality as we delve more deeply into the structure of the DGA.  Despite the algebraic nature of the results, I promise pictures, examples, and analogies with Morse Theory.  This is joint work with Jason Ma (Duke).</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>    </div>    <div class="day">      <div class="day_title">        Tuesday, March 10      </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"> Roberto  Frigerio  (Pisa)</div><div class="event_title">Bounded cohomology classes from measurable differential forms <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Let S be a complete hyperbolic surface. Via integration over geodesic simplices, any bounded differential 2-form on S defines a degree-2 bounded cohomology class in H^2_b(S). It was proved by Barge and Ghys that, if S is closed, this procedure defines an injective embedding of the (infinite-dimensional) space of differential 2-forms on S into H^2_b(S). We extend Barge and Ghys’ Theorem in two directions, showing that the same result holds under the weaker hypothesis that S is of parabolic type (this holds, for example, when it has finite area), and letting forms vary among all measurable bounded 2-forms on S, rather than only among smooth ones.Our argument is different from Barge and Ghys’ original one, and relies on the proof of a fact of independent interest: ideal triangles in the hyperbolic plane are Pompeiu sets.This is joint work with Gian Maria Dall\'Ara and Ervin Hadziosmanovic.</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_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/algebraische-geometrie/">Seminar Algebra and Geometry</a></div><br /><div class="event_speaker"> Claudia Stadlmayr (Universität Neuchâtel)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/seminar-algebra-and-geometry-claudia-stadlmayr-universitaet-neuchatel/">Infinitesimal symmetry in algebraic geometry: group schemes and del Pezzo surfaces</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Group schemes provide a refined notion of symmetry in positive characteristic: they detect infinitesimal structure invisible to the discrete automorphism group. Classical examples such as mu_p or alpha_p equip the trivial topological space with a non-trivial algebraic structure. In this talk I will explain how this perspective can be used to classify weak and RDP del Pezzo surfaces admitting global vector fields, and how phenomena unique to small characteristic - such as non-lifting vector fields on rational double point singularities (RDPs) - can be illuminated using the group-scheme framework. If time permits, I will outline applications and ongoing projects: towards higher-dimensional Fano varieties with infinite automorphism groups, (equivariant) compactifications of the affine plane, group scheme torsors and their smoothness behavior.</div><div class="event_time">10:30 &bull; Universität Basel, Spiegelgasse 5, Seminarraum 05.002</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.unil.ch/dsa/en/home/menuinst/seminaires--evenements/research-seminars.html">Talks in Actuarial Mathematics </a></div><br /><div class="event_speaker"> Pierre-Olivier  Goffard  (Université de Strasbourg)</div><div class="event_title">Independent groups of dependent contracts: a variance reduction technique for Monte Carlo estimation of the loss distribution of parametric insurance portfolios <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />This study analyzes the aggregated losses of weather-indexed insurance portfolios, using precipitation-based triggers across France as a case study. We employ a spatio-temporal stochastic process to simulate rainfall scenarios over a one-year period at multiple locations, aiming to estimate the cumulative indemnity distribution. Our methodology implements a two-step variance reduction technique:(1) clustering of contracts based on their spatio-temporal dependence structure, and(2) construction of representative contracts for each resulting cluster. We theoretically justify and empirically demonstrate that this aggregation approach reduces the variance of the loss distribution estimator compared to crude Monte Carlo methods. Our framework is model-agnostic as it is applicable to any stochastic weather model or index of interest.</div><div class="event_time">14:00 &bull; EPF Lausanne, Extranef 125</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"> Erman  Isik  (Bilkent University)</div><div class="event_title">The growth of Tate-Shafarevich groups of p-supersingular elliptic curves over anticyclotomic Zp-extensions at inert primes <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In this talk, we will discuss the asymptotic growth of both the Mordell-Weil ranks and the Tate–Shafarevich groups for an elliptic curve E defined over the rational numbers, focusing on its behaviour along the anticyclotomic Zp-extension of an imaginary quadratic K. Here, p is a prime at which E has good supersingular reduction and is inert in K. We will review the definitions and properties of the plus and minus Selmer groups from Iwasawa theory and discuss how these groups can be used to derive arithmetic information about the elliptic curve.</div><div class="event_time">15:00 &bull; <a class="external" href="https://tinyurl.com/UniDistanceNTSeminar">UniDistance Suisse, Zoom</a></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/analysis-seminar">Analysis Seminar</a></div><br /><div class="event_speaker"> Carl Johansson (EFPL )</div><div class="event_title">Lyapunov exponents and asymptotic mixing in DiPerna-Lions flows <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In 2003, A. Bressan proposed a conjecture concerning the mixing efficiency of incompressible flows, which remains open. I will survey progress toward its resolution and present a new result establishing the asymptotic validity of the conjecture for time-periodic velocity fields. This is achieved by adapting tools from smooth ergodic theory, such as Lyapunov exponents, to the non-smooth setting of DiPerna-Lions flows. This is joint work with Elia Brué and Maria Colombo.</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_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/mat075.1">Zurich Graduate Colloquium</a></div><br /><div class="event_speaker">Chiara Donatone (Università degli Studi di Milano)</div><div class="event_title">What is... an RBG link? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;div dir="ltr" data-olk-copy-source="MessageBody">A link is a smoothly embedded closed 1-dimensional submanifold in the 3-dimensional sphere S^3. In this talk we study a particular class of links, known as RBG links, and present some results arising from this framework in low-dimensional topology, &nbsp;the study of smooth manifolds of&nbsp; dimension 4 or less.&lt;/div> &lt;div dir="ltr">&nbsp;&lt;/div> &lt;div>We will see how RBG links can be used to construct pairs of knots sharing a specific topological feature, that is having orientation preserving diffeomorphic traces. As notable applications of this framework, we will see that the Conway knot is not smoothly slice and has a friend for every integer slope.&lt;/div></div><div class="event_time">16:05 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room F 26.3</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/news-and-events/events/lecture-series/alice-roth-lectures.html">Alice Roth Lectures</a></div><br /><div class="event_speaker"> Isabelle Gallagher (Institut de Mathématiques de Jussieu)</div><div class="event_title">From microscopic to macroscopic: how to reconcile different mathematical descriptions of gases?</div><div class="event_time">17:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room F 30</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Wednesday, March 11      </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://www.math.uzh.ch/mat760">Ergodic theory and dynamical systems seminar</a></div><br /><div class="event_speaker">Colin Guillarmou (CNRS and Université Paris-Saclay)</div><div class="event_title">On the marked length spectrum of surfaces with Anosov geodesic flow. <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: #ffffff; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">We show that the marked length spectrum determines the isometry class for surfaces with Anosov geodesic flows. This extends a result of Otal and Croke, known previously in negative curvature. This is joint work with Lefeuvre and Paternain.&lt;/span>&lt;/p></div><div class="event_time">13:30 &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_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"> Beatrice Bernasconi (ETH Zürich)</div><div class="event_title">Dynamical Sarkisov length in the plane Cremona group <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We will give an overview of the Sarkisov program in higher dimension and then describe it in the case of rational surfaces. We will define the Cremona group over the projective plane and some dynamical invariants for its elements. Finally, we will look at a very special dynamical invariant, namely the Sarkisov length.</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://uzh.ch">Universit&auml;t Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://www.math.uzh.ch/aa/?events">Neuchatel - St.Gallen - Zurich Seminar in Coding Theory and Cryptography</a></div><br /><div class="event_speaker">Prof. Dr. Francisco Javier Lobillo Borrero (Universidad de Granada)</div><div class="event_title">A Hybrid Approach to Post-quantum Cryptography: Integrating Mceliece Structures Into Knapsack Criptosystems <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>This talk introduces a novel IND-CCA2 Key EncapsulationMechanism (KEM) based on the weighted subset sum problem. The&nbsp;cryptosystem uses a decoding algorithm inspired by Goppa codes, adapted for the ring of integers. Decryption is efficiently handled through a truncated version of the extended Euclidean algorithm. By allowin&nbsp;non-binary alphabets, the design aims to mitigate traditional lattice-reduction attacks that have historically compromised knapsack schemes.&lt;/p> &lt;p>Additionally, to protect the system against lattice-reduction attacks to&nbsp;the private key, two possible masking mechanisms of the public key are&nbsp;proposed. Since the system is based on basic integer arithmetic, it offers high computational performance and it is potentially secure&nbsp;against quantum attacks.&lt;/p></div><div class="event_time">15:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 28</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"> Marc Abboud (Université de Neuchâtel)</div><div class="event_title">A uniform bound on common periodic points in families of regular plane polynomial automorphisms <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A regular plane polynomial automorphism is a subclass of polynomial diffeomorphism f: C^2 - > C^2 of the complex affine plane with positive topological entropy. Every polynomial diffeomorphism of positive topological entropy is conjugated to a regular one. Dujardin and Favre showed that two such transformations cannot share infinitely many periodic points unless they share a common iterate. We show that this results holds uniformly in a family: Take two 1-parameter families of regular plane polynomial automorphisms (f_t) and (g_t), then there exists a constant D >0 such that for every parameter t except for a finite number of them f_t and g_t share at most D periodic points. This generalises a result of Mavraki and Schmidt who showed it for endomorphisms of the projective line. I will give a brief overview of the history of this problem and explain key tools of the proof which is based on the theory of adelic divisors and arithmetic equidistribution. This is joint work with Yugang Zhang.</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_be"><a class="external" href="https://www.unibe.ch">Universität Bern</a></div><div class="event_type"><a class="external" href="https://www.imsv.unibe.ch/research/talks/colloquia/index_eng.html">Colloquia on Probability and Statistics </a></div><br /><div class="event_speaker">Dr. Catherine Wolfram (ETH Zurich)</div><div class="event_title"><a class="external" href="https://www.imsv.unibe.ch/research/talks/schedule/index_eng.html">The dimer model in three dimensions</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A dimer tiling (or perfect matching) of Z^d is a collection of edges which covers each vertex exactly once. The dimer model is the study of random dimer tilings. I will focus on questions about what random dimer tilings look like in the scaling limit, that is, on larger and larger subgraphs of Z^d. In two dimensions, the dimer model is exactly solvable, and many things are known about this (large deviations, limit shapes with an explicit description, Gaussian fluctuations…). The dimer model does not seem to be exactly solvable in higher dimensions (as is the case for many statistical mechanics models), and we know much less. In this talk, I’ll explain what the dimer model is, give some intuition for why two and three dimensions are different to study, explain the main large deviation result we prove for random dimer tilings of Z^3, and show simulations of random tilings. This is based on joint work with Nishant Chandgotia and Scott Sheffield.</div><div class="event_time">16:15 &bull; Universität Bern, Hörsaal B78, ExWi, Sidlerstrasse 5, 3012 Bern</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/aa/?events">Neuchatel - St.Gallen - Zurich Seminar in Coding Theory and Cryptography</a></div><br /><div class="event_speaker">Andrea Di Giusto (Eindhoven University of Technology)</div><div class="event_title">The Service Rate Problem in Distributed Storage and Non-systematic Recovery Systems <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>Data centres are one of the backbones of modern-day digital infrastructure, with the amount of processed and stored data growing year by year. In this context, coding techniques are employed to ensure the availability and reliability of the stored data. &nbsp;One question that has recently emerged, is how to optimally store a certain number of data objects on a certain number of servers in a way that allows the system to serve certain amounts of requests for the objects. This problem is naturally phrased as a coding question, as it concerns the design of a redundancy strategy for the storage system. In this talk, we will introduce and formalize the service problem and the Service Rate Region as a measure of system flexibility. Connection to other well-established research topics will be outlined, such as PIR/batch codes and Majority Logic Decoding. The difference between systematic and non-systematic systems will be considered, and we will show how the latter can give a better performance when designed carefully.&lt;/p></div><div class="event_time">16:30 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 28</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://math.ethz.ch/s/seminar-on-stochastic-processes">Seminar on Stochastic Processes</a></div><br /><div class="event_speaker">Prof. Dr. Loïc Béthancourt (Université Sorbonne Paris Nord)</div><div class="event_title">Fractional diffusion limit in convex domain and reflected isotropic stable processes <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In this talk, I will present some recent results obtained with Nicolas Fournier. We are interested in a simple model describing the (random) motion of a particle in a gaz, namely the kinetic scattering equation. When the particle lives in $\\mathbb{R}^d$, and when the equilibrium (for the velocities) is heavy-tailed, it is easy to see that the position process, correctly rescaled, converges weakly to an $\\alpha$-stable process. We are interested in the case where the particle is confined into a convex smooth domain, by a certain reflection mechanism that I will describe. We show that, according to the boundary condition, two different types of reflected stable process may arise at the limit. After introducing the model and the results, I will mostly explain how we construct the limiting processes by piecing together their excursions inside the domain. If time permits, I will say a few words about the convergence.</div><div class="event_time">17:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room  H12</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Thursday, March 12      </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"> Sylvain Crovisier (Université Paris-Saclay)</div><div class="event_title">Ergodic theory of surface diffeomorphisms</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_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"> Alessio Cangini (Universität Basel)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/studium/mathematik/doktorat/bernoullis-tafelrunde/detail/bernoullis-tafelrunde-alessio-cangini/">A lower bound for the canonical height in cyclotomic extensions</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Abstract Arithmetic Dynamics studies number-theoretic properties of algebraic numbers under iteration of a polynomial or rational function. The ideas and techniques in this field draw from both complex dynamics and number theory. Central to this theory are the notions of local and global canonical heights, which are functions that measure the arithmetic complexity of orbits. In this talk, we will first introduce the necessary background from complex dynamics. Then we will discuss the key properties of canonical heights. Finally, we will present ongoing work on establishing lower bounds for the global canonical height in cyclotomic extensions.</div><div class="event_time">12:15 &bull; Universität Basel, Seminarraum 05.001, Spiegelgasse 5</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://calendar.google.com/calendar/embed?mode=AGENDA&height=600&wkst=2&bgcolor=%23FFFFFF&src=t36it03v52cus2detrvinlgk18%40group.calendar.google.com&color=%235F6B02&ctz=Europe%2FZurich">Groups, Arithmetic and Algebraic Geometry Seminar </a></div><br /><div class="event_speaker"> Keyu  Wang  (University of Vienna)</div><div class="event_title">Title T.B.A.</div><div class="event_time">13:15 &bull; EPF Lausanne</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/daco-seminar">DACO Seminar</a></div><br /><div class="event_speaker"> Robert Wang (University of Waterloo, CA)</div><div class="event_title">Derandomizing Matrix Concentration Inequalities from Free Probability <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Recently, sharp matrix concentration inequalities were developed using the theory of free probability. In this work, we design polynomial time deterministic algorithms to construct outcomes that satisfy the guarantees of these inequalities. As direct consequences, we obtain polynomial time deterministic algorithms for the matrix Spencer problem and for constructing near-Ramanujan graphs. Our proofs show that the concepts and techniques in free probability are useful not only for mathematical analyses but also for efficient computations.</div><div class="event_time">14:15 &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_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/sfs/news-and-events/data-science-seminar">ETH-FDS seminar </a></div><br /><div class="event_speaker"> Robert Scheichl (Heidelberg University)</div><div class="event_title">Trainspotting: Measure Transport using Tensor Decomposition <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />General multivariate distributions are notoriously expensive to sample from, particularly the high-dimensional posterior distributions in PDE-constrained inverse problems. In this talk, I will present a measure transport based approach for Bayesian inverse problems based on low-rank surrogates in the tensor train format, a methodology that has been exploited for many years for scalable, high-dimensional density function approximation in quantum physics and chemistry. We build upon recent developments in the field of cross approximation algorithms in linear algebra to construct a tensor train approximation to the target probability density function using a small number of function evaluations. For sufficiently smooth distributions, the storage required for accurate tensor train approximations is moderate, scaling linearly with dimension. In turn, the structure of the tensor train (TT) surrogate allows sampling by an efficient conditional distribution method since marginal distributions are computable with linear complexity in dimension. Using this generic tool enables conditional sampling, construction of optimal biasing densities or even tractable Bayesian optimal experimental design. In order to keep the arising ranks in the TT approximations manageable, we furthermore propose a ‘deep’ version of the approach where the transport from reference to target distribution is approximated incrementally via intermediate bridging densities. The method is demonstrated in the context of complex PDE-constrained Bayesian inverse problems, computing expectations of functionals of the PDE solution with respect to high-dimensional posterior distributions, including rare event probabilities and optimal experimental designs.</div><div class="event_time">16:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room E 5</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/mat675.1">PDE and Mathematical Physics</a></div><br /><div class="event_speaker">Dr. Renato Velozo Ruiz (Imperial College London)</div><div class="event_title">Phase mixing and the Vlasov equation in cosmology <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;div>In this talk, we will consider the Vlasov equation on expanding isotropic homogeneous tori described by the Friedmann&ndash;Lema&icirc;tre&ndash;Robertson&ndash;Walker cosmological spacetimes. For expansion rate $t^q$, with $0 &lt; q \\leq 1/2$ (excluding some exceptional values), we show that the difference of a&nbsp;time-normalised spatial density with the spatial average decays with a quantitative rate depending on the regularity of the initial datum.&lt;/div> &lt;div>&nbsp;&lt;/div> &lt;div class="elementToProof">This is joint work with Martin Taylor (Imperial College London).&lt;/div></div><div class="event_time">16:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 35/36</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/talks-in-financial-and-insurance-mathematics">Talks in Financial and Insurance Mathematics</a></div><br /><div class="event_speaker">Prof. Dr. Pierre-Olivier Goffard (Université de Strasbourg)</div><div class="event_title">Collaborative and parametric insurance on the Ethereum blockchain <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will present a blockchain-based insurance scheme that integrates parametric and collaborative elements. A pool of investors, referred to as surplus providers, locks funds in a smart contract, enabling blockchain users to underwrite parametric insurance contracts. These contracts automatically trigger compensation when predefined conditions are met. The collaborative aspect is embodied in the generation of tokens, which are distributed to both surplus providers and policyholders. These tokens represent each participant\'s share of the surplus and grant voting rights for management decisions. The smart contract is developed in Solidity, a high-level programming language for the Ethereum blockchain, and deployed on the Sepolia testnet, with data processing and analysis conducted using Python. I will discuss both the technical details as well as the actuarial aspects.</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">        Friday, March 13      </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"> Tom Hutchcroft (California Institute of Technology (Caltech))</div><div class="event_title">Dimension dependence of critical phenomena in percolation</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_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"> Matthias Ospel (Deutsch-Französisches Forschungsinstitut Saint-Louis)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/event/details/seminar-in-numerical-analysis-matthias-ospel-deutsch-franzoesisches-forschungsinstitut-saint-louis/">Towards robust discretizations and solvers for the time-harmonic Maxwell equations in complex media</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In this talk, we revisit multi-source localization from the perspective of the time-domain wave equation. Under a high-frequency approximation, the wave equation reduces to the eikonal equation, whose solutions describe travel-time fields. We show how numerical solutions of the forward problem governed by the eikonal equation can be used to address the inverse problem of localizing impulsive sources in topographically complex environments. We also consider classical free-field solvers and the problem of localizing multiple sources in the presence of clutter, timing uncertainty, incomplete data, and an unknown source count. To address these challenges, we introduce a combinatorial coalition-based model solved via set packing, enabling joint data association, source counting, and multi-source localization. Monte Carlo simulations and acoustic experiments in urban environments illustrate the behavior of the proposed methods. The presentation emphasizes the conceptual bridge between wave propagation and robust multi-source localization. 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://memento.epfl.ch/MATHS/?period=14">Computational Mathematics Seminar </a></div><br /><div class="event_speaker"> John  Urschel (MIT)</div><div class="event_title">Title T.B.A.</div><div class="event_time">12:15 &bull; EPF Lausanne, CM 1 517</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/number-theory-seminar">Number Theory Seminar</a></div><br /><div class="event_speaker">Dr. Weixiao Lu (Institut de Mathématique de Marseille)</div><div class="event_title">Automorphic period and sum of L-values <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The relative Langlands duality posed by Ben-Zvi-Sakellaridis-Venkatesh predicts that periods of automorphic form can sometimes equal to sum of several special values of automorphic L-functions rather than a single one. In this talk, I will present explicit evidence for this phenomenon. I will discuss families of automorphic periods on general linear groups and classical groups that are designed to detect specific types of Eisenstein series. These periods indeed evaluate to finite sums of L-values. This is joint work with Guodong Xi.</div><div class="event_time">14:15 &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://www.epfl.ch/schools/sb/research/math/statistics-seminars/">Statistics Seminar </a></div><br /><div class="event_speaker"> Andrew  Nobel (Chapel Hill)</div><div class="event_title">Title T.B.A.</div><div class="event_time">15:15 &bull; EPF Lausanne, CM 1 517</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"> Lycka Drakengren (ETH Zürich)</div><div class="event_title">The Prym map near the locus of decomposable abelian varieties <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We study the codifferential of the Prym map at the double covers of smooth curves whose Prym varieties decompose nontrivially as a product of abelian varieties, to show that the fiber product of the Prym map R_g -> A_(g-1) and the product map A_k x A_(g-1-k) -> A_(g-1) for 1 &#8804; k &#8804; (g-1)/2 is smooth.</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>';