var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-10"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-8"><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. 6</span>      <span style="float: right; text-align:right; width: 250px;">20.10 - 24.10.2025</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, October 20      </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"> Jiaye Wei</div><div class="event_title">Robustness of Matching and the Backup Nodes Problem <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We study the following problem on the robustness of matching. Consider a bipartite graph with parts A and B. We assume that B has a larger size than A and that the graph has an A-perfect matching. The goal is to find an A-perfect matching such that the number of nodes in A which has a neighbor in the unsaturated nodes of B, is maximized; in other words, we want the maximum number of A nodes to have “backup nodes”. A related problem is studied in the setting of second bidder auctions with binary bids by Azar, Birnbaum, Karlin, and Nguyen in 2009. In that problem, the condition of finding a perfect matching is relaxed but every A nodes in the matching is required to have backup nodes. In this talk, I will first explain a tight (1-1/e) approximation for the general Backup Nodes problem via submodular maximization. I will also introduce the results for the degree-constrained case, including a polynomial-time exact algorithm for (d,2)-regular graphs and the APX-hardness for graphs with small degrees. This is joint work with Rom Pinchasi, Neta Singer, and Lukas Vogl.</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/talks-in-mathematical-physics">Talks in Mathematical Physics</a></div><br /><div class="event_speaker"> Vladimir Dotsenko (University of Strasbourg)</div><div class="event_title">Higher-dimensional Givental symmetries <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Some 20 years ago, Chen, Gibney and Krashen introduced beautiful algebraic varieties parametrizing "pointed trees of projective spaces"; these varieties generalize the celebrated Deligne-Mumford compactifications of moduli spaces of genus zero curves with marked points. In the latter case, the homology operad encodes the tree level part of a cohomological field theory. It follows from the work of Givental and many others that the space of all such structures on a given graded vector space has a very rich symmetry group; this fact has been used in many different research areas. In this talk, I shall prove that the homology of the operad made of Chen-Gibney-Krashen spaces possesses many interesting properties, and in particular, there are higher-dimensional Givental symmetries that emerge in this story. Curiously enough, this leads to new results on classical Givental symmetries as well. This is joint work with Eduardo Hoefel, Sergey Shadrin and Grigory Solomadin.</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/talks-in-mathematical-physics">Talks in Mathematical Physics</a></div><br /><div class="event_speaker"> Bruno Vallette (Université Sorbonne Paris Nord)</div><div class="event_title">Operadic Calculus for Higher Colour-Kinematics Duality <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />This talk aims at providing gauge field theory, in particular colour–kinematics duality and the double copy construction, with the required higher algebraic structures. From the algebro-homotopical perspective, a classical field theory is encoded by a cyclic homotopy Lie algebra whose Maurer–Cartan functional defines the action. For many gauge theories of interest, including Chern–Simons and Yang–Mills, this algebra splits as a tensor product of a cyclic Lie algebra, the colour Lie algebra, and a cyclic homotopy-commutative algebra, the kinematic algebra.The duality between colour and kinematics, first observed by Bern–Carrasco–Johansson in the study of Yang–Mills amplitudes, suggests that the kinematic algebra carries a Lie-type structure. For theories with at most cubic interactions, this structure is captured by coexact Batalin-Vilkovisky (BV) algebras, algebraic objects dual to the exact BV algebras arising in Poisson geometry. To incorporate higher-order interactions, following ideas of M. Reiterer, a homotopy refinement of this notion becomes necessary.The purpose of this talk is to provide a conceptual definition of homotopy coexact BV algebras, expressed in relation to homotopy commutative and BV algebras, together with a concrete operadic model. Our framework gives explicit presentations in terms of generating operations and relations and enables the systematic application of homotopical methods—including homotopy transfer, rectification, infinity-morphisms, and deformation theory—to the resulting algebras. The quartic-level structures recently identified in Yang–Mills theory fits naturally into this framework. This is a joint work with Anibal Medina-Mardones.</div><div class="event_time">14:45 &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/symplectic-geometry-seminar">Symplectic Geometry Seminar</a></div><br /><div class="event_speaker"> Ipsita Datta (ETH)</div><div class="event_title">Geometry of Lagrangian Tangles <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Lagrangian tangles are cobordisms between smooth links that generalize the classical Arnol\'d theory of Lagrangian cobordism and the theory of Lagrangian cobordisms between Legendrian links.  In this talk, we will explore the symplectic geometry of Lagrangian tangle links in the product of a surface with the complex numbers.  The main tool is a novel Floer theory for Lagrangian tangles inspired by Morse theory for manifolds with a gradient field tangent to the boundary.  We show the existence of an LES of persistence modules giving quantitative obstructions to the existence of Lagrangian tangle links.This is joint work with Josh Sabloff (Haverford College).</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"> Aleksei Kulikov (University of Copenhagen)</div><div class="event_title">Time-frequency localization operator and its eigenvalues <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />For a set A &#8834; R^d we denote by P_A the projection onto A and by Q_A = F&#8315;¹P_A F the Fourier projection onto A, where F is the Fourier transform. For a pair of sets A, B &#8834; R^d the time-frequency localization operator associated with A and B is the operator S_{A,B} = P_A Q_B P_A.This is a self-adjoint operator satisfying 0 &#8804; S_{A,B} &#8804; Id. If A and B have finite measures then S_{A,B} is a Hilbert–Schmidt operator, in particular it is compact and so we have a sequence of eigenvalues 1 > &#955;&#8321;(A, B) &#8805; &#955;&#8322;(A, B) &#8805; ... &#8805; 0.If A = cA&#8321;, B = cB&#8321; for some fixed nice sets A&#8321;, B&#8321; and a big parameter c then the eigenvalues exhibit a phase transition: first &#8776; c²&#7496;|A&#8321;||B&#8321;| of the eigenvalues are very close to 1, then there are only &#8776; c²&#7496;&#8315;¹ log(c) intermediate eigenvalues, and the remaining eigenvalues tend to 0 extremely fast. Moreover, for fixed &#949; > 0 if we consider the counting function N_{c,&#949;} = #{n : &#949; &lt; &#955;&#8345;(c) &lt; 1 &#8722; &#949;} then the dependence on 1/c is logarithmic as well. In this talk we will discuss the uniformity of the estimates on N_{c,&#949;} when &#949; is small. For a wide range of parameters we show a uniform bound c²&#7496;&#8315;¹ log(c)/ log(1/&#949;). Moreover, it turns out that if &#949; is extremely small, for example if &#949; &lt; c&#8315;&#7491;, then the log(c) term disappears and the estimate becomes even better than expected.The talk is based on joint works with Fedor Nazarov and with Martin Dam Larsen.</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. Maria Colombo (EPFL)</div><div class="event_title"><a class="external" href="https://www.math.unibe.ch/research/talks/colloquium/index_eng.html">Instability, Non-uniqueness, and Unpredictability in Fluid Equations</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In the last 20 years, there have been remarkable progress in understanding non-uniqueness of solutions to the fundamental partial differential equations of incompressible fluid dynamics, namely, the Euler and Navier-Stokes equations. They stem from different viewpoints: just to mention a few, they include convex integration, instability in self-similar variables, numerical evidences. The talk will provide an overview of these developments, focussing on results about the 2 dimensional Euler equations. It will also highlight new results showing that solutions obtained in the vanishing viscosity limit from the (well-posed) Navier-Stokes equations can be nonunique.</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, October 21      </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"> Yury Neretin (Graz)</div><div class="event_title">Infinite symmetric group and concatenations of  bordisms of triangulated surfaces <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The infinite symmetric group is the group of finitely supported permutations of natural numbers N. We consider the  product G of three copies of the infinite symmetric group. Denote by K the diagonal subgroup, which also is an infinite symmetric group and consider the subgroup K(n) of K fixing the first n elements of N. We show that double cosets {K(n)\\G/K(n)} have a natural structure of a semigroup, and moreover there is a natural multiplication K(n)\\G/K(m) x K(m)\\G/K(l) ->  K(l). We get a category, and this category acts in any unitary representation of the group G. We assign to each morphism of this category a triangulated surfaces colored black and white in checker order and show that morphisms correspond to concatenation of surfaces.The talk does not require any preliminary knowledge of representation theory.</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_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"> Andrew Graham (University of Oxford)</div><div class="event_title">  p-adic Fourier theory in families <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will describe a generalisation of the p-adic Fourier theory of Amice and Schneider--Teitelbaum to families of p-divisible rigid analytic groups. As an application, one can construct global Eisenstein measures over the modular curve which give rise to new families of quaternionic modular forms. This is joint work with P. van Hoften and S. Howe.</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_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. Nicolaos  Kapouleas (Brown University)</div><div class="event_title">Minimal surface and hypersurface doublings <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />After a brief historical review I will concentrate on recent and ongoing work on constructions of hypersurface doublings (with J. Zou),results on the index and nullity of minimal surface doublings in the round three-sphere (with Zou), results on some Yau questions for minimal surfaces in the round three-sphere (with Mcgrath), on general doubling constructions in the case the base surface hasnontrivial kernel for the Jacobi operator (with Zou), and finally various open questions.</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://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">Michaël Maex (KU Leuven)</div><div class="event_title">What is... the skeleton of a curve? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>Skeleta of Berkovich spaces link together the worlds of combinatorics, arithmetic geometry, analytic geometry, tropical geometry and resolution of singularities. Rather than getting lost into tedious details, this talk aims to give an overview of historic and recent developments of non-archimedean geometry in the sense of Tate and Berkovich in a way that is understandable by any graduate student in mathematics.<br>We will introduce non-archimedean fields and how they historically led to a new type of analytic space. Then we discuss analogies between geometry of Berkovich spaces and complex spaces, which is captured by skeleta. Finally we discuss different different ways of obtaining skeleta and canonical forms can play a key role in this, and further reduce the dependence on tools from algebraic geometry.&lt;/p></div><div class="event_time">16:30 &bull; UZH Zentrum, Building KO2, Room F 150</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Wednesday, October 22      </div>      <div class="day_content">        <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/mat760">Ergodic theory and dynamical systems seminar</a></div><br /><div class="event_speaker">Prof. Dr. Giovanni Forni (University of Maryland and CY Cergy Paris Université)</div><div class="event_title">Some new results on non-rational polygonal billiards <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;div>The dynamics of billiards&nbsp;in non-rational polygons&lt;/div> &lt;div>is rather poorly understood for lack&nbsp;of tools, in particular&nbsp;&lt;/div> &lt;div>the lack of a renormalization theory.&nbsp; In this talk, we focus&lt;/div> &lt;div>on results which can be proved by harmonic&nbsp;analysis tools,&lt;/div> &lt;div>in particular results&nbsp;on the cohomological equation for the flow&lt;/div> &lt;div>and results on dynamical properties of the holonomy foliation.&nbsp;&lt;/div> &lt;div>This is joint work with N. Moll.&lt;/div></div><div class="event_time">13:30 &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://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. Sam Canning (ETH Zürich)</div><div class="event_title">Cohomology of the Satake compactification I</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/sam/news-and-events/zhacm-colloquia">Zurich Colloquium in Applied and Computational Mathematics</a></div><br /><div class="event_speaker">Dr. Fernando Henriquez Barraza (TU Vienna)</div><div class="event_title">Shape Holomorphy of Boundary Integral Operators with Applications to Uncertainty Quantification <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We consider a family of boundary integral operators (BIOs) arisingfrom the boundary reduction of well-posed problems—either Laplace or Helmholtz—defined on a collection of parametrically described domains. Our goal is to establish the holomorphic (analytic) dependence of theseBIOs, as well as of the solutions to associated boundary integral equations, on perturbations of the domain shape, a property commonly referred to as shape holomorphy.To date, various results have addressed shape holomorphy under differing assumptions, particularly concerning the physical dimension of the problem and, most notably, the smoothness of the domain deformations. In this talk, we present recent results on the shape holomorphy of BIOs under Lipschitz-regular deformations.We also discuss the implications of these findings for the developmentof computational methods in forward and inverse uncertainty quantification, as well as model order reduction.</div><div class="event_time">16:30 &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/seminar-on-stochastic-processes">Seminar on Stochastic Processes</a></div><br /><div class="event_speaker">Prof. Dr. Maksim Zhukovskii (University of Sheffield)</div><div class="event_title">Sharp thresholds for spanning regular subgraphs <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A graph property is called increasing if it is closed under addition of edges. For an increasing property, the probability of its occurrence in the binomial random graph G(n,p) transitions rapidly (in asymptotics) from 0 to 1 as p crosses the so-called probability threshold. Since the original paper of Erd&#337;s and Rényi the task of determining the asymptotic behaviour of threshold probabilities for increasing properties has been a central topic in probabilistic combinatorics. While the asymptotic order of the probability threshold has been determined for many natural increasing graph properties, a general solution remains unknown, and determining the exact asymptotics is even more challenging. In the talk I will provide an answer to the latter question for a class of increasing properties generated by d-regular graphs. This family of d-regular graphs contains asymptotically almost all d-regular graphs and, in particular, it contains the square of a cycle. This resolves a conjecture of Kahn, Narayanan, and Park, regarding the asymptotics of the threshold for the appearance of the square of a Hamilton cycle.</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, October 23      </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_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"> Jacopo  Papalini  (University of Gent)</div><div class="event_title">Sine dilaton gravity: wormholes, finite matrices and q-holography <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will discuss a two-dimensional dilaton gravity theory with a sine potential. At the disk level, this theory admits a microscopic holographic realization as the double-scaled SYK model. Remarkably, in the open channel canonical quantization of the theory, the momentum conjugate to the length of two-sided Cauchy slices becomes periodic. As a result, the ERB length in sine dilaton gravity is discretized upon gauging this symmetry. For closed Cauchy slices, a similar discretization occurs in the physical Hilbert space, corresponding to a discrete spectrum for the length of the necks of trumpet geometries. By appropriately gluing two such trumpets together, one can then construct a wormhole geometry in sine dilaton gravity whose amplitude matches the spectral correlation functions of a one-cut matrix integral. This correspondence suggests that the theory provides a path integral formulation of q-deformed JT gravity, where the matrix size is large but finite, thus going beyond the regime of the double-scaled SYK model. Finally, I will describe how this theory of gravity can be regarded as a realization of q-deformed holography and propose a possible implementation of this framework to study the near-horizon dynamics of near-extremal de Sitter black holes. </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_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"> Virgile Constantin (EPFL)</div><div class="event_title">Higher Covering Maps, Deck Transformations, and Yoneda in an &#8734;-Topos <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />A classical and elementary result in topology identifies the group of deck transformations of a normal covering map (with discrete fibers) with a quotient of the fundamental group. In this talk, I will explain how to internalize this result in a fixed &#8734;-topos E, obtaining an isomorphism of group objects in E. Even better, for coverings with (n-1)-truncated fibers, we obtain an analogous isomorphism of n-group objects between the deck transformation n-group and a suitable quotient of the fundamental n-group. The key input is an internal form of the Yoneda lemma (and embedding) in E; I will present and motivate its formulation, and highlight its central role in the proof. As a direct corollary, we obtain a uniqueness result for quotients of higher groups. The talk is designed to be accessible: no prior knowledge of &#8734;-topoi is necessary.</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_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://k-os.math.ethz.ch">[K-OS] Knot Online Seminar</a></div><br /><div class="event_speaker"> Marc Kegel (Universidad de Sevilla)</div><div class="event_title">Unique Surgery Descriptions along Knots <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 prove that for any non-trivial knot K, infinitely many r-surgeries K(r) along K have a unique surgery description along a knot. Conversely, we will discuss the optimality of this result by providing new families of manifolds admitting different surgery descriptions. This is based on joint work with Misha Schmalian.</div><div class="event_time">16:15 &bull; <a class="external" href="https://u-paris.zoom.us/j/87853056962">online</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/sfs/news-and-events/data-science-seminar">ETH-FDS seminar </a></div><br /><div class="event_speaker"> Tilmann Gneiting (HITS, Heidelberg)</div><div class="event_title">Assessing Monotone Dependence <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The assessment of monotone dependence between random variables $X$ and $Y$ is a classical problem in statistics and a gamut of application domains.  Consequently, researchers have sought measures of association that are invariant under strictly increasing transformations of the margins, with the extant literature being splintered.  Rank correlation coefficients, such as Spearman\'s Rho and Kendall\'s Tau, have been studied at great length in the statistical literature, mostly under the assumption that $X$ and $Y$ are continuous.  In the case of a dichotomous outcome $Y$, receiver operating characteristic (ROC) analysis and the asymmetric area under the ROC curve (AUC) measure are used to assess monotone dependence of $Y$ on a covariate $X$.  In this talk I demonstrate that the two thus far disconnected strands of literature can be unified and bridged, by developing common population level theory, common estimators, and common tests that apply to all types of linearly ordered outcomes. In case studies, we assess progress in artificial intelligence (AI) based weather prediction and evaluate methods of uncertainty quantification for the output of large language models.  The talk is based on joint work with Eva-Maria Walz and Andreas Eberl.</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://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. Julien Sabin (IRMAR, Université de Rennes)</div><div class="event_title">Large time behaviour of the positive density Hartree equation <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>The Hartree equation is a quantum version of the nonlinear Vlasov equation in the sense that it is a mean-field approximation of the many-body dynamics (classical for Vlasov, quantum for Hartree). In this talk I will present results concerning the asymptotic stability of homogeneous equilibria for the Hartree equation, which is a quantum version of the "Landau damping" results for the Vlasov equation. This is a joint work in collaboration with Antoine Borie (Rennes) and Sonae Hadama (Kyoto).&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"> Tobias Kohn (KIT Karlsruhe)</div><div class="event_title">Zwei Schwestern: Mathematik und Informatik im Fluss der Zeit <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Die Informatik ist so stark von der Mathematik geprägt und durchdrungen, dass die Unterschiede zwischen den beiden Disziplinen manchmal fast zu verschwinden scheinen.  Gerade Kernbegriffe wie Variablen, Funktionen und Algorithmen werden im Mathematikunterricht bereits seit Jahrzehnten gelehrt;  kann der Informatikunterricht da überhaupt noch einen neuen und eigenständigen Beitrag leisten?  Bei genauerer Betrachtung zeigt sich aber schnell, dass sich hinter dem gemeinsamen Vokabular mitunter gänzlich verschiedene Konzepte verbergen und die Informatik letztlich eine neue Sichtweise dazu liefert, was wir überhaupt wissen, erkennen und lernen können.</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_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">Dr. Philipp Schmocker (ETH Zurich)</div><div class="event_title">Deep inverse problem for double phase equation <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br /> We use neural operators to learn the coefficient-to-solution map for nonlinear elliptic equations of double phase type. Since the solution is the unique minimizer of the convex splitting problem involving the two double phase functionals over a uniformly convex and uniformly smooth Banach space, we approximate the coefficient-to-solution map by a generative equilibrium operator (GEO). For training, we concatenate the GEO with the reconstruction formula of the coefficient to learn its right-inverse on the coefficient space. Once trained, this approach allows us to efficiently predict solutions of the double phase equation for other coefficients. Further applications of these neural operators are presented in the context of portfolio optimization and quadratic hedging.</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, October 24      </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/number-theory-seminar">Number Theory Seminar</a></div><br /><div class="event_speaker">Dr. Amina  Abdurrahman (IHÉS)</div><div class="event_title">A cohomological formula for symplectic L-functions and applications <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 topological perspective on the order of the Tate-Shafarevich group up to squares as an application of a formula established in previous joint work with A. Venkatesh which gives a cohomological expression for the central value of symplectic L-functions on curves. I will sketch ideas of the proofs, and in particular the analogous picture in topology that is crucial in the arithmetic proofs.</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_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. Donggun Lee (IBS Center for Complex Geometry (Daejeon))</div><div class="event_title">Representations on the cohomology of the moduli space of pointed rational 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 pointed rational curves carries a natural action of the symmetric group permuting the marked points. In this talk, I will present combinatorial and recursive formulas for the induced representations on its cohomology. These formulas are obtained by relating the representation to that of the moduli space with one additional marked point fixed under the symmetric group action, which has a particularly nice and tractable structure. Taking the invariant subspace, in particular, leads to an effective inductive formula for the Betti numbers of the moduli space of rational curves with unordered markings. I will also discuss several interesting conjectural properties of these representations. This talk is based on joint work with Jinwon Choi and Young-Hoon Kiem.</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>';