var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-8"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-6"><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. 15</span>      <span style="float: right; text-align:right; width: 250px;">27.5 - 31.5.2024</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Spring Semester 2024</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, May 27      </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://www.epfl.ch/labs/cmgr/cmgr/geometry-seminar">Geometry Seminar</a></div><br /><div class="event_speaker"> Stéphane Saboureau  (Univ Paris-Est Créteil)</div><div class="event_title">Minimal volume entropy of simplicial complexes <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The volume entropy of a finite simplicial complex X with a length metric is defined as the exponential growth rate of the volume of balls in its universal cover. The infimum of the volume entropy over all metrics on X of unit volume is a topological invariant, called the minimal volume entropy. A problem of central importance is to determine under which topological assumption the minimal volume entropy of a closed manifold or of a finite simplicial complex is nonzero. We will present various results around this problem. Joint work with Ivan Babenko.</div><div class="event_time">11:00 &bull; EPF Lausanne, Room CM 1 517</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"> Valentyna Pavliv (Basel)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/studium/mathematik/doktorat/bernoullis-tafelrunde/detail/bernoullis-tafelrunde-valentyna-pavliv-basel/">No Transparency for Smart Toys</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />abstract</div><div class="event_time">12:15 &bull; Universität Basel, Seminarraum 05.002</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"> Léonie Papon (University of Durham)</div><div class="event_title">A level line of the massive Gaussian free field <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 coupling between a massive planar Gaussian free field (GFF) and a random curve in which the curve can be interpreted as the level of the field. This coupling is constructed by reweighting the law of the standard GFF-SLE_4 coupling. I will then show that in this coupling, the marginal law of the curve is that of a massive version of SLE_4, called massive SLE_4. This law on curves was introduced by Makarov and Smirnov to describe the scaling limit of a massive version of the harmonic explorer. Time permitting, I will also explain how to reweight the law of the coupling GFF-CLE_4 to obtain a coupling between a massive GFF and a massive version of CLE_4.</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. Fulvio Gesmundo (Université Paul Sabatier, Toulouse)</div><div class="event_title"><a class="external" href="https://www.math.unibe.ch/research/talks/colloquium/index_eng.html">Rational points on 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 />A number of complexity problems in theoretical computer science can be interpreted in terms of membership of an object encoding the problem into an algebraic variety representing a complexity class.Two major problems in algebraic complexity theory, that is determining the exponent of matrix multiplication and Valiant\'s VP vs VNP flagship conjecture, fall into this framework. In this seminar, I will give an overview of classical methods from geometry and representation theory to study membership in these algebraic varieties and in turn obtain lower bounds in computational complexity.</div><div class="event_time">17:15 &bull; Universität Bern, Sidlerstrasse 5, 3012 Bern, Lecture Room B6</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/stiefel-lectures">ETH-FDS Stiefel Lectures</a></div><br /><div class="event_speaker"> Sebastien  Bubeck (Microsoft )</div><div class="event_title">Small Language Models <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Large language models (LLMs) have taken the field of AI by storm. But how large do they really need to be? I\'ll discuss the phi series of models from Microsoft, which exhibit many of the striking emergent properties of LLMs despite having merely a few billion parameters.</div><div class="event_time">17:30 &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">        Tuesday, May 28      </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"> Umut Çetin (London School of Economics)</div><div class="event_title">Mathematics of Market Microstructure</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_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"> Alejandra  Garrido  (Universidad Complutense de Madrid)</div><div class="event_title">Simple locally compact groups from full groups and branch groups <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Since the start of the century there has been increased interest in totally disconnected locally compact (tdlc) groups and a structure theory is starting to emerge. A special role is played by the class S of tdlc groups that are compactly generated, topologically simple and not discrete. The theory is in need of more examples with a view to some sort of classification. Full groups of homeomorphisms of Cantor space are a rich source of simple groups. In joint work with Colin Reid, it is shown that, given the right conditions on the "seed" group, the full group can be given a totally disconnected locally compact topology and it contains a big simple compactly generated subgroup. An example of this is Neretin\'s group of almost automorphisms of a tree.  Further examples include commensurators of profinite regular branch groups and full groups of Burger-Mozes universal groups.It is also shown that this construction accounts for all groups in one of the five types of groups in S, up to local isomorphism (the totally disconnected analogue of having the same Lie algebra in the connected case).I will focus more on the examples than on the theory, since we are looking for more examples than those above. </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://uzh.ch">Universit&auml;t Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://www.math.uzh.ch/mat770.1">Oberseminar: Algebraische Geometrie</a></div><br /><div class="event_speaker">Dr. Johannes Krah (University of Bielefeld)</div><div class="event_title">On proper splinters in positive characteristic <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A scheme X is a splinter if for any finite surjective morphism f: Y \\to X the pullback map O_X \\to f_* O_Y splits as O_X-modules. By the direct summand conjecture, now a theorem due to André, every regular Noetherian ring is a splinter. Whilst for affine schemes the splinter property can be viewed as a local measure of singularity, the splinter property imposes strong constraints on the global geometry of proper schemes over a field of positive characteristic. For instance, the structure sheaf of a proper splinter in positive characteristic has vanishing positive-degree cohomology. I will report on joint work with Charles Vial concerning further obstructions on the global geometry of proper splinters in positive characteristic.</div><div class="event_time">13:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 25</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"><a class="external" href="https://sites.math.washington.edu/~rothvoss/">Prof. Dr. Thomas Rothvoss (University of Washington, US)</a></div><div class="event_title">The Subspace Flatness Conjecture and Faster Integer Programming <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In a seminal paper, Kannan and Lov\\’asz (1988) considered a quantity $\\mu_{KL}(\\Lambda,K)$which denotes the best volume-based lower bound on the \\emph{covering radius} $\\mu(\\Lambda,K)$ of a convexbody $K$ with respect to a lattice $\\Lambda$. Kannan and Lov\\’asz proved that $\\mu(\\Lambda,K) \\leq n \\cdot \\mu_{KL}(\\Lambda,K)$ and the Subspace Flatness Conjecture by Dadush (2012) claims a $O(\\log n)$ factor suffices, which would matchthe lower bound from the work of Kannan and Lov\\’asz.We settle this conjecture up to a constant in the exponent by proving that  $\\mu(\\Lambda,K) \\leq O(\\log^{3}(n)) \\cdot \\mu_{KL} (\\Lambda,K)$. Our proof isbased on the Reverse Minkowski Theorem due to Regev and Stephens-Davidowitz (2017).Following the work of Dadush (2012, 2019), we obtain a $(\\log n)^{O(n)}$-time randomized algorithm tosolve integer programs in $n$ variables.Another implication of our main result is a near-optimal \\emph{flatness constant} of $O(n \\log^{3}(n))$.This is joint work with Victor Reis.</div><div class="event_time">14:15 &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://math.ethz.ch/s/analysis-seminar">Analysis Seminar</a></div><br /><div class="event_speaker">Prof. Dr. Antoine  Gloria (Sorbonne Université)</div><div class="event_title">What is large-scale regularity? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The aim of this talk is to investigate what survives of the standard estimates valid for operators with constant coefficients in the case of variable coefficients. The general strategy is based on quantifying how far the (inverse) operator with variable coefficients is from an (inverse) operator with constant coefficients, and obtain the desired estimates by perturbation. Whereas this is classically done at the level of the coefficients themselves (Meyers’ estimates, Schauder theory e.g.), in this talk I will use closeness in the sense of homogenization. As an illustration, I will discuss large-scale Meyers’ estimates, large-scale Lipschitz estimates, and conclude with large-scale dispersive estimates.</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/seminaires/lie-sem/">Lie groups and moduli spaces </a></div><br /><div class="event_speaker"> Rodrigo Navarro Betancourt (Dublin)</div><div class="event_title">Kashiwara-Vergne from string topology <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The group KRV acts transitively and freely on solutions to the Kashiwara-Vergne conjecture, a problem in Lie theory alluding to the Baker-Campbell-Hausdorff series. Alekseev-Kawazumi-Kuno-Naef showed that, surprisingly, KRV can be recovered from the group of automorphisms of the Goldman-Turaev Lie bialgebra of the thrice-punctured sphere. The Goldman bracket and the Turaev cobracket are defined on homotopy classes of free loops, and they are both instances of intersection products stemming from string topology. In this talk, we will give a new characterisation of KRV exploiting this tie to string topology.</div><div class="event_time">15:30 &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">Dr. Samir Canning (ETHZ)</div><div class="event_title">What is... the cohomology of moduli spaces of curves? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />\'\'The moduli space of curves was first studied by Riemann. I will explain what it is, how to compactify it, and how to attempt to compute the cohomology of its compactifications. Ideas from a broad range of mathematics are necessary, including low dimensional topology, algebraic geometry, and number theory.</div><div class="event_time">16:30 &bull; UZH Zentrum, Building KO2, Room F 150</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"><a class="external" href="https://math.ethz.ch/people/adinis">Dr. André Guerra (ETH Z&uuml;rich, Switzerland)</a></div><div class="event_title">Harmonic maps and the vectorial obstacle problem: singularities vs free boundaries <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will discuss some recent results obtained in collaboration with A. Figalli, S. Kim and H. Shahgholian. We consider minimizers of the Dirichlet energy among maps constrained to take values outside a smooth domain O in R^m. These minimizers can be thought of as solutions of a vectorial obstacle problem, or as harmonic maps into the manifold-with-boundary given by the complement of O. I will discuss results concerning the regularity of the minimizers, the location of their singularities, and the structure of the free boundary.</div><div class="event_time">16:30 &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">        Wednesday, May 29      </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://www.epfl.ch/labs/hessbellwald-lab/epfl-applied-topology-seminar-spring-2024/">Seminar of Applied Topology </a></div><br /><div class="event_speaker"> Marzieh Eidi</div><div class="event_title">Title T.B.A.</div><div class="event_time">10:15 &bull; EPF Lausanne, MA B1 524</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">  Various Speakers</div><div class="event_title">Random Matrix Day <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A day of talks on Random Matrix Theory, in an informal environment encouraging discussion. The planned scheduled is:10:15-11:00 Afonso Bandeira11:15-12:00 Antti Knowles14:15-15:00 Ashkan Nikeghbali15:15-16:00 Dominik Schroder16:15-17:00 Benjamin Schlein</div><div class="event_time">10:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room E 41</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_fr"><a class="external" href="https://www.unifr.ch">Université de Fribourg</a></div><div class="event_type"><a class="external" href="https://commonweb.unifr.ch/_Science/Math/Pub/Math/seminars/OSgeom-top.html">Oberseminar Geometrie</a></div><br /><div class="event_speaker"> Ruth Kellerhals (UniFr)</div><div class="event_title">The Euler characteristic of hyperbolic orbifolds <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 shall review a few results about the Euler characteristicof hyperbolic space forms and then present some of my past and recentwork characterising hyperbolic orbifolds of minimal volume in even andodd dimensions.</div><div class="event_time">10:20 &bull; Université de Fribourg, room Phys 2.52</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/mat760">Ergodic theory and dynamical systems seminar</a></div><br /><div class="event_speaker">Magali Jay (Aix-Marseille Université)</div><div class="event_title">Tiling billiard in the wind-tree model <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 the meeting of different dynamical systems: tiling billiards, the wind-tree model and Eaton lenses. The three of them are motivated by physics. The wind-tree model was instoduced by Paul and Tatyana Ehrenfest to study a gaz: a particule is moving in a plane where obstacles are periodically placed, on which the particule bounces. The Eaton lenses are a periodic array of lenses in the plane, in which we consider a light ray that is reflected each time it crosses a lens. In the beginning of the 2000&#039;s, physicists have conceived metamaterials with negative index of refraction. Tilling billiards&#039; trajectories consist of light rays moving in a arrangement of metamaterials with opposite indew of refraction. After having introduced these dynamical systems, I will consider a mix of them: an arrangement of rectangles in the plane, like in the wind-tree model, but made of metamaterials, like for tiling billiards. I study the trajectories of light in this plane. They are refracted each time they cross a rectangle. I show that these trajectories are traped in a strip, for almost every parameter. This behavior is similar to the one of Eaton lenses.</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/geometry-seminar">Geometry Seminar</a></div><br /><div class="event_speaker"><a class="external" href="https://math.ethz.ch/people/curech">Dr. Christian Urech (ETH Z&uuml;rich, Switzerland)</a></div><div class="event_title">Cremona groups and CAT(0) cube complexes <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The Cremona group of rank n is the group of birational transformations of the projective n-space. Cremona groups have been studied for around 150 years and attracted a lot of attention in the last decades due to their rich group theoretical and dynamical properties. In this talk, I will first give a short introduction to Cremona groups (no prior knowledge of algebraic geometry assumed). Then I will present natural constructions of CAT(0) cube complexes on which Cremona groups act by isometries, and explain how we can deduce old and new results from this action. This is joint work with Anne Lonjou.</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">Prof. Dr. Serte Donderwinkel (University of Groningen)</div><div class="event_title">Counting graphic sequences (and score sequences) via random walks <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A graphic sequence is a non-increasing sequence of natural numbers that can occur as the degree sequence of a graph. We show that the number of graphic sequences of length n grows like cn^{-3/4}4^n for some constant c, answering a question by Royle. The foundation of our proof consists of a few reformulations that turn our problem into a question about the lazy simple symmetric random walk bridge. To be precise, we calculate the asymptotic probability that the integral of a (lazy) simple symmetric random walk bridge never goes negative. Our reformulation also yields a new, efficient algorithm for exact enumeration of graphic sequences, with which we are able to calculate many more exact values than previously known. This talk is based on joint work with Paul Balister, Carla Groenland, Tom Johnston and Alex Scott. In the last part of the talk, I will also touch upon a work with Brett Kolesnik, in which we use random walk techniques to show that the possible (non-increasing) score sequences of a round-robin tournament with n players grows like c\'n^{-5/2}4^n for some constant c\', answering a question by Erdös and Moser. We also obtain a Brownian scaling limit of a uniformly random score sequence.</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, May 30      </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"> Umut Çetin (London School of Economics)</div><div class="event_title">Mathematics of Market Microstructure</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_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/~palmeran/topsem.html">Séminaire de Topologie et Géométrie </a></div><br /><div class="event_speaker"> Françoise  Michel  (IMT Toulouse)</div><div class="event_title">Topologie des germes de Surface complexe et topologie de la normalisation <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Il s’agira d’un exposé pour non-spécialistes.On définira type analytique, type topologique et « link » d’un germe de surface complexe. On se basera sur les exemples suivants de germes d’hypersurfaces: zˆn&#8722; xyˆq = 0. On décrira les « links » topologiquement singuliers. On expliquera pourquoi la topologie d’un germe à singularités non isolées détermine la topologie de sa normalisée. On donnera les liens avec les singularités cycliques quotients et la résolution d’Hirzebruch-Yung.</div><div class="event_time">14:15 &bull; Université de Genève, Conseil Général 7-9, Room 1-15</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_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"> Richard Rimanyi</div><div class="event_title">Title T.B.A.</div><div class="event_time">14:15 &bull; EPF Lausanne</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. Min Jun Jo (Duke University)</div><div class="event_title">Cusp formation in singular vortex patches <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />\'We prove the instantaneous cusp formation from a single corner of the vortex patch solutions. This positively settles the conjecture given by Cohen-Danchin in Multiscale approximation of vortex patches, SIAM J. Appl. Math. 60 (2000), no. 2, 477-502. This is a joint work with Tarek Elgindi (Duke University).\'</div><div class="event_time">16:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 46</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Friday, May 31      </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://sites.google.com/view/pm-seminar/home">Physical Mathematics Seminar</a></div><br /><div class="event_speaker"> Ioannis  Tsiares (CEA/IPhT, Paris)</div><div class="event_title">On the Virasoro fusion kernel at c=25 <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 novel expression for the Virasoro fusion kernel in two-dimensional CFTs with central charge c=25. The expression exhibits an intricate relation with the connection coefficient of the Painlevé VI differential equation and agrees with previously known integral representations of the kernel. In the process of deriving this formula, we uncover a new symmetry in the shift relations satisfied by both the Virasoro modular and fusion kernels at generic central charge. The symmetry formally interchanges a solution valid at central charge c with another solution valid at 26 &#8722; c, much like the relation between the DOZZ formula for Liouville theory\'s structure constants and its \'\'time-like\'\' cousin. We will conclude by discussing a reformulation of the Virasoro bootstrap problem that incorporates the power of the Virasoro kernels, in an attempt to understand \'\'irrational\'\' 2d CFTs with c>1.</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/seminar-in-numerical-analysis">Seminar in Numerical Analysis</a></div><br /><div class="event_speaker"> Philipp Trunschke (University of Nantes)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/seminar-in-numerical-analysis-philipp-trunschke-university-of-nantes/">Using weights for fun and profit: Weighted sparse and low-rank approximation</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Many functions of interest exhibit weighted summability of their coefficients with respect to some dictionary of basis functions. This summability enables efficient s parse and low-rank approximation and ensures that the function can be estimated efficiently from samples. This talk presents some fundamental results on the estimation of sparse and low-rank functions, like the weighted Stechkin lemma and the restricted isometry property, and introduces simultaneously sparse and low-rank tensor formats. For further information about the seminar, please visit this webpage .</div><div class="event_time">11:00 &bull; Universität Basel</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>';