var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-76"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-74"><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;">29.5 - 2.6.2023</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Spring Semester 2023</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, May 29      </div>      <div class="day_content">        <div class="day_content_item no_event">        No events scheduled today!        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Tuesday, 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"> Karoly Böröczky (Alfréd Rényi Institute of Mathematics)</div><div class="event_title">The Isoperimetric inequality, the Brunn-Minkowski theory, and the Lp Minkowski problem</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.unine.ch/math/home/colloques_et_seminaires/seminaires-de-linstitut.html">Séminaire Groupes et Géométrie </a></div><br /><div class="event_speaker"> Christoforos Neofytidis (Ohio State University)</div><div class="event_title">Numerical invariants monotone under the Gromov order <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We suggest a Kodaira dimension for geometric manifolds (in the sense of Thurston and more generally) and study its monotonicity with respect to the existence of maps of non-zero degree, as well as its relationship with other monotone invariants, such as the simplicial volume. Part of this talk is based on joint work with Weiyi Zhang.</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://algebra.dmi.unibas.ch/seminar.html">Seminar Algebra and Geometry</a></div><br /><div class="event_speaker"> Pascal Fong (Université Paris-Saclay)</div><div class="event_title">Title T.B.A.</div><div class="event_time">10:30 &bull; Universität Basel, Spiegelgasse 5, SR 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"> Hamza Hanbali (Monash University, Melbourne, Australia)</div><div class="event_title">Mean-variance longevity risk-sharing for annuity contracts <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />This paper investigates longevity risk-sharing as a solution to the sustainability and affordability problems in the annuity market, and in particular how much longevity risk could be transferred back to policyholders under a mean-variance utility framework. First, it provides dynamic risk-sharing rules for annuities. Second, it studies the contract properties from the perspectives of both the provider and individual policyholders. Third, in policyholders’ decision, it highlights and accounts for two levels of uncertainty and two levels of correlation induced by systematic longevity risk. Fourth, it provides necessary and sufficient conditions on the premium loading and the share of transferred risk, such that both parties prefer risk-sharing. The analytical and numerical results of the paper offer a deeper understanding of the effects of systematic and diversifiable risks on those preferences, and show that the products presented in this paper are suitable retirement solutions.</div><div class="event_time">11:00 &bull; EPF Lausanne, UniL campus, Extranef - 109</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">Prof. Dr. Daniel Smania (Instituto de Ciências Matemáticas e de Computação USP)</div><div class="event_title">Deformations of one-dimensional dynamical systems <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Perhaps one of the main features of one-dimensional dynamics (either real or complex) is that the theory of deformations is rich. By this we mean that the topological classes of such maps often are infinite dimensional manifolds, but with finite codimension. They are kind of "almost" structurally stable! Moreover for smooth families of maps inside a given topological class the associated family of conjugacies also moves in a smooth way. There are various applications in the study of renormalisation theory and linear response theory. There is a nice theory in complex dynamics but for real maps with finite smoothness on the interval our current understanding is far behind the complex setting. We will discuss recent developments obtained in joint work with Clodoaldo Ragazzo but also some results with Viviane Baladi and Amanda de Lima. Ergodic theory will be a crucial tool.</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_ge"><a class="external" href="https://unige.ch">Université de Genève</a></div><div class="event_type"><a class="external" href="https://www.unige.ch/math/annonces/seminaire-danalyse-numerique">Séminaire d\'Analyse Numérique </a></div><br /><div class="event_speaker"> Goncalo Dos Reis (University of Edinburgh)</div><div class="event_title">High order splitting methods for stochastic differential equations <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 how ideas from rough path theory can be leveraged to develop high order numerical methods for SDEs. To motivate our approach, we consider what happens when the Brownian motion driving an SDE is replaced by a piecewise linear path. We show that this procedure transforms the SDE into a sequence of ODEs – which can then be discretized using an appropriate ODE solver. Moreover, to achieve a high accuracy, we construct these piecewise linear paths to match certain “iterated” integrals of the Brownian motion. At the same time, the ODE sequences obtained from this path-based approach can be interpreted as a splitting method, which neatly connects our work to the existing literature. For example, we show that the well-known Strang splitting falls under this framework and can be modified to give an improved convergence rate. We will conclude the talk with a couple of examples, demonstrating the flexibility and convergence properties of our methodology.</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_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://math.ethz.ch/people/felixku"> Felix Kuchelmeister (ETH Z&uuml;rich, Switzerland)</a></div><div class="event_title">Finite sample rates for logistic regression with small noise or few samples <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The logistic regression estimator is known to inflate the magnitude of its coefficients if the sample size n is small, the dimension p is (moderately) large or the signal-to-noise ratio 1/\\sigma is large (probabilities of observing a label are close to 0 or 1). With this in mind, we study the logistic regression estimator with p &lt;&lt; n/\\log n, assuming Gaussian covariates and labels generated by the Gaussian link function, with a mild optimization constraint on the estimator\'s length to ensure existence. We provide finite sample guarantees for its direction, which serves as a classifier, and its Euclidean norm, which is an estimator for the signal-to-noise ratio. We distinguish between two regimes. In the low-noise/small-sample regime (n\\sigma &lt;= p\\log n), we show that the estimator\'s direction (and consequentially the classification error) achieve the rate (p\\log n)/n - as if the problem was noiseless. In this case, the norm of the estimator is at least of order n/(p\\log n). If instead n\\sigma >= p\\log n, the estimator\'s direction achieves the rate \\sqrt{\\sigma p\\log n/n}, whereas its norm converges to the true norm at the rate \\sqrt{p\\log n/(n\\sigma^3)}. As a corollary, the data are not linearly separable with high probability in this regime. The logistic regression estimator allows to conclude which regime occurs with high probability. Therefore, inference for logistic regression is possible in the regime n\\sigma >= p\\log n. In either case, logistic regression provides a competitive classifier.This is joint work with Sara van de Geer. </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_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"> Marc Abboud (Université de Rennes 1)</div><div class="event_title">Dynamical degrees of endomorphisms of affine surfaces <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Let $f: \\mathbf C^2 \\rightarrow \\mathbf C^2$ be a polynomial transformation. The dynamical degree of $f$ is defined as $\\lim_n (\\text{deg} f^n)^{1/n}$, where $\\text{deg} f^n$ is the degree of the $n$-th iterate of $f$. In 2007, Favre and Jonsson showed that the dynamical degree of any polynomial endomorphism of $\\mathbf C^2$ is an algebraic integer of degree $\\leq 2$. For any affine surface, there is a definition of the dynamical degree that generalizes the one on the affine plane. We show that the result still holds in this case: the dynamical degree of an endomorphism of any complex affine surface is an algebraic integer of degree $\\leq 2$. In this talk, I will give an overview of the recent results obtained on dynamical degrees on algebraic varieties and explain the key tools of the proof.</div><div class="event_time">14:15 &bull; EPF Lausanne, Salle MA A3 30</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"> Peter Friz (TU Berlin)</div><div class="event_title">Rough analysis of local stochastic volatility models <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Local stochastic volatility models are a class of (in general non-Markovian) diffusion models that have become standard in the financial industry, largely due to an efficient McKean-Vlasov particle calibration algorithm, mathematically not yet fully understood. In this talk we address the pricing problem, that is, the computation of certain expectations. We proceed by a partial conditioning that exhibits a rough semimartingale &  SDE structure, topic of recent investigations with P. Zorin-Kranich, K. Lê , A. Hocquet and the speaker. In particular, we exploit partial (rough) Markovianity to compute certain conditional expectations via rough partial differential equations (RPDEs), later randomized with martingale rough paths. As far as the speaker knows, the resulting (formal) SPDE is beyond existing SPDE theory. Joint work with P. Bank (TU Berlin), C. Bayer and L. Pelizzari (both WIAS Berlin).</div><div class="event_time">15:00 &bull; EPF Lausanne, Bernoulli Center</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. Lennart Döppenschmitt (Universität Zürich)</div><div class="event_title">What is... a brane? <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will attempt to give an answer in three parts. First I will argue that branes appear naturally as boundary conditions in quantum field theories, in particular, we will observe how Lagrangian branes are suitable boundary conditions in the topological A-model. We will proceed with a swift introductory "101" on generalized complex geometry to properly fortify our understanding of branes in the mathematical sense. Well-equipped with the proper language, we will go through three and a half examples among which is a new(ish) perspective on Kähler metrics as branes (yes, metrics can be branes). If time permits we will finish with a quick look at the role that branes play in the story of mirror symmetry à la Strominger-Yau-Zaslow.</div><div class="event_time">16:15 &bull; UZH Zentrum, Building KO2, Room F 150</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Wednesday, May 31      </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"> Shahar Mendelson (The Australian National University)</div><div class="event_title">Probabilistic methods in Analysis</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_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"> Mathias Blaise (Université de Fribourg)</div><div class="event_title">On isometric invariants of cusped hyperbolic manifolds <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Since the development initiated by Thurston, hyperbolic geometry plays a fundamental role in dimension three and beyond. In this work we consider cusped hyperbolic manifolds, that is, non-compact Riemannian manifolds of constant curvature &#8722;1, and we give bounds for three isometric invariants for such manifolds: the volume, the radius of the biggest embedded ball (inradius) and the length of a shortest closed geodesic(systole). The lower volume bound is a result of Meyerhoff, Adams and Kellerhals, wheras the bounds for the inradius and the systole are due to Gendulphe. One particular 3-manifold stands out in this situation: the Gieseking manifold M&#8727;. Constructed originally by face-pairing isometries of an ideal regular tetrahedron, the Gieseking manifold M&#8727; is the unique cusped hyperbolic 3-manifold of minimal volume, up to isometry. Furthermore, we show that M&#8727; realizes both the inradius bound and the systolic bound. While the systolic upper bound is attained by M&#8727; and the (orientable) figure-eight knot complement, only, it is not yet knowni f the inradius bound characterizes M&#8727; up to isometry. Important tools and techniques in this work are densities of (horo-)ball packings in Euclidean and hyperbolic space, explicit formulae for the simplicial density function, hyperbolic trigonometry and various bounds for the dilation length of loxodromic isometries.</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://math.ethz.ch/s/algebraic-geometry-and-moduli-seminar">Algebraic Geometry and Moduli Seminar</a></div><br /><div class="event_speaker">Prof. Dr. Aaron Pixton (University of Michigan)</div><div class="event_title">Admissible covers and stable maps <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Given a space parametrizing branched covers of smooth curves (with some given genus, degree, and ramification profile data), there are two well-known compactifications - the admissible covers of Harris and Mumford and the stable maps of (relative) Gromov-Witten theory. Both of these compactifications give rise to cycles on moduli spaces of stable curves. I will describe work in progress giving a way to translate between the cycles produced by the two compactifications. Part of this talk presents joint work with Q. Zhao.</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_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"> Sebastián Herrero (PUCV Chile & ETH Zürich)</div><div class="event_title">Special values of modular functions and S-units <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The values of modular functions at complex multiplication points are classically used to construct explicit abelian extensions of quadratic imaginary fields. The factorization of (the algebraic norm of) these numbers is also a problem that has been extensively studied, at least since the beginnings of the 1900s. More recently, particular attention has been given to the question of when these values are algebraic units, and more generally how often these special values are S-units when S is a fixed finite set of prime numbers. In this talk I will present a brief overview of known results and open related problems, and I will explain joint work with Ricardo Menares (PUC Chile) and Juan Rivera-Letelier (U. of Rochester) on the finiteness of special values of modular functions that are S-units.Mehr Details»  In meinen Kalender kopieren</div><div class="event_time">14:15 &bull; EPF Lausanne, Salle MA A3 30</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">Danai Hansmann (University of Zurich)</div><div class="event_title">Bounds on the asymptotic rate of block codes <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 investigate the behavior of families of codes and study their asymptotic rate and relative distance. A function representing the best achievable information rate for a fixed relative distance is defined and shown to be continuous. Determining the exact values of this function is considered very difficult and remains an open problem. Consequently, various upper bounds will be presented and compared. We will also present a construction of a new upper bound. &lt;BR> &lt;BR> (**This eSeminar will take place over Zoom, using the same meeting details as previous seminars. If you do not have meeting details, please contact zita.fiquelideabreu@math.uzh.ch **)</div><div class="event_time">15:00 &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/geometry-seminar">Geometry Seminar</a></div><br /><div class="event_speaker"> Gonzalo Ruiz Stolowicz (EPF Lausanne)</div><div class="event_title">Hyperbolic representations of SL_2(R) <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We will briefly review the representations of groups in infinite-dimensional hyperbolic spaces. In particular, the family of SL2(R) representations will be studied, an operation on them that resembles a convex combination will be introduced and a partial classification will be presented. </div><div class="event_time">15:45 &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">Rocco Mora (Inria-Paris)</div><div class="event_title">Polynomial time attack on high rate random alternant codes <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 present a polynomial-time key-recovery algorithm retrieving the algebraic structure of a high-rate alternant code. This positively answers the long-standing open question regarding whether the distinguisher of high-rate alternant or Goppa codes can be turned into an attack. In particular, our algorithm works for all distinguishable parameters as long as the code is a generic alternant code and when the code field size q is either 2 or 3. This has been achieved by two different ingredients: (i) a way of using code shortening and the component-wise product of codes to derive from the original alternant code a sequence of alternant codes of decreasing degree up to getting an alternant code of degree 3; (ii) an original Gröbner basis approach that takes into account the non-standard constraints on the multiplier and support of an alternant code and that recovers in polynomial time the relevant algebraic structure of an alternant code of degree 3. &lt;BR> &lt;BR> (**This eSeminar will take place over Zoom, using the same meeting details as previous seminars. If you do not have meeting details, please contact zita.fiquelideabreu@math.uzh.ch **)</div><div class="event_time">16:30 &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/news-and-events/events/lecture-series/inaugural-and-farewell-lectures.html">Farewell Lectures</a></div><br /><div class="event_speaker">Prof. Dr. Sara van de Geer</div><div class="event_title">Data dust </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 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://stat.ethz.ch/events/research_seminar">Research Seminar in Statistics</a></div><br /><div class="event_speaker"> Sara  van de Geer (ETH Zürich)</div><div class="event_title">Farewell Lecture: Data dust  <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />tba</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 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://stat.ethz.ch/events/zukost">ZüKoSt Zürcher Kolloquium über Statistik</a></div><br /><div class="event_speaker"> Sara van de Geer (ETH Zürich)</div><div class="event_title">Farewell Lecture: Data dust <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Farewell Lecture</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">        Thursday, June 1      </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"> Brita Nucinkis (Royal Holloway, University of London)</div><div class="event_title">Cohomological methods in group theory</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 cancelled"><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"> Ping Xu (Pennsylvania State University)</div><div class="event_title">CANCELLED: Derived differentiable  manifolds <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />One of the main motivations behind derived differential geometry is to deal with singularities arising from zero loci or intersections of submanifolds. Both cases can be considered as fiber products of manifolds which may not be smooth in classical differential geometry. Thus we need to extend the category of differentiable manifolds to a larger category in which one can talk about "homotopy fiber products". In this talk, we will discuss a solution to this problem in terms of dg manifolds.  The talk is mainly based on a joint work with Kai Behrend and Hsuan-Yi Liao.</div><div class="event_time">14:00 &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/zahlentheorie/">Seminar Zahlentheorie</a></div><br /><div class="event_speaker"> Jakob Glas (Universität Salzburg & ETH Zürich)</div><div class="event_title">Title T.B.A.</div><div class="event_time">14:15 &bull; Universität Basel, Spiegelgasse 5, SR 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/~palmeran/topsem.html">Séminaire de Topologie et Géométrie </a></div><br /><div class="event_speaker"> Emmanuel Wagner (Université de Paris)</div><div class="event_title"> Algebraic vs geometric categorification of the Alexander polynomial : a spectral sequel <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We construct a spectral sequence from the gl0-homology, an algebraic categorification of the Alexander polynomial to the knot Floer homology. This spectral sequence is of Bockstein type and comes from a subtle manipulation of coefficients. The main tools are quantum traces of foams and of singular Soergel bimodules.<br>This is a joint work with Anna Beliakova, Kris Putyra, and Louis-Hadrien Robert.</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"> Prahlad Sharma (Renyi Institute)</div><div class="event_title">Bilinear sums with $GL(2)$ coefficients and the exponent of distribution of $d_3$ <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We obtain the exponent of distribution $1/2+1/30$ for the ternary divisor function $d_3$ to square-free and prime power moduli, improving the previous results of Fouvry--Kowalski--Michel, Heath-Brown, and Friedlander--Iwaniec. The key input is certain estimates on bilinear sums with $GL(2)$ coefficients obtained using the delta symbol approach. </div><div class="event_time">14:15 &bull; EPF Lausanne, Salle MA A3 30</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"> Benoit Dherin (Google)</div><div class="event_title">Deep learning basics and the problem of implicit regularization <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In the first part of this talk, we will recall the building blocks of deep learning, framing the learning problem as an optimization problem solved in practice by gradient descent. This first part will be very accessible and self-contained. Then we will attempt to convey how surprising it is that deep learning works so well given the extreme complexity of its solution space, pointing toward the existence of an implicit regularization mechanism self-selecting the simpler solutions that generalize best ahead of the more complex ones that do not perform well. At last, we will outline a recent approach attempting to uncover such an implicit regularization mechanism based on the backward error analysis of the gradient descent scheme.</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://math.ethz.ch/sfs/news-and-events/data-science-seminar">ETH-FDS seminar </a></div><br /><div class="event_speaker"> Yurii  Nesterov (UCLouvain)</div><div class="event_title">New perspectives for higher-order methods in Convex Optimization <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In the recent years, the most important developments in Optimization were related to clarification of abilities of the higher-order methods. These schemes have potentially much higher rate of convergence as compared to the lower-order methods. However, the possibility of their implementation in the form of practically efficient algorithms was questionable during decades. In this talk, we discuss different possibilities for advancing in this direction, which avoid all standard fears on tensor methods (memory requirements, complexity of computing the tensor components, etc.). Moreover, in this way we get the new second-order methods with memory, which converge provably faster than the conventional upper limits provided by the Complexity Theory. </div><div class="event_time">16:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room D 1.2</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://www.ntwebseminar.org/">Number Theory Web Seminar</a></div><br /><div class="event_speaker"> Lior Bary-Soroker (Tel Aviv University)</div><div class="event_title">Random additive polynomials <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Random polynomials with integer coefficients tend to be irreducible and to have a large Galois group with high probability. This was shown more than a century ago in the large box model, where we choose the coefficients uniformly from a box and let its size go to infinity, while only recently there are results in the restricted box model, when the size of the box is bounded and its dimension (i.e. the degree of the polynomial) goes to infinity. <br>In this talk, we will discuss an important class of random polynomials — additive polynomials, which have coefficients in the polynomial ring over a finite field. In this case, the roots form a vector space, hence the Galois group is naturally a subgroup of GLn. <br>While we prove that the Galois group is the full matrix group both in the large box model, and in the large finite field limit, our main result is in the restricted box model: under some necessary condition the Galois group is large (in the sense that it contains SLn) asymptotically almost surely, as the degree goes to infinity.The proof relies crucially on deep results on subgroups of GLn by Fulman and Guralnick, combined with tools from algebra and number theory. <br>Based on a joint work with Alexei Entin and Eilidh McKemmie.</div><div class="event_time">17:00 &bull; Universität Basel, online Seminar</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"><a class="external" href="https://www.ceremade.dauphine.fr/~carlier/">Prof. Dr. Guillaume Carlier (Université Paris Dauphine)</a></div><div class="event_title">A variant of Hewitt and Savage theorem for finitely exchangeable laws and applications to optimal transport <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 describe a variant of the Hewitt and Savage theorem for laws of exchangeable finite families of random variables as well as their marginals. This representation reveals the role of some universal polynomials of measures which contain correlated correction terms and capture the geometry of extreme points of symmetric laws and their marginals. I will also describe possible applications to some multi-marginal optimal problems with symmetries. This is based on a joint work with Gero Friesecke and Daniela Vögler (TU Munich).</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 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/talks-in-mathematical-physics">Talks in Mathematical Physics</a></div><br /><div class="event_speaker"> Benoit Dherin (Google)</div><div class="event_title">Why neural networks find (geometrically) simple solutions <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We will start by defining a notion of geometric complexity for neural networks based on intuitive notions of volume and energy. This will be motivated by the visualization of training sequences in the case of simple 1d neural regressions. Then we will explain why for neural networks the optimization process creates a pressure to keep the network geometric complexity low. Additionally, we will see that manyother common heuristics in the training of neural networks (frominitialization schemes to explicit regularization strategies) have as a side effect to also keep the geometric complexity of the learnedsolutions low. We will conclude by explaining how this points toward apreference toward a form of harmonic maps built in the commonly used training and tuning heuristics in deep learning.</div><div class="event_time">17:15 &bull; UZH Irchel, Winterthurerstrasse 190, Z&uuml;rich, Building Y27, Room H 12</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Friday, June 2      </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">Prof. Dr. Tim Browning (ISTA)</div><div class="event_title">Hasse principle for random varieties <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I\'ll discuss efforts to understand the solubility of random Diophantine equations, focusing on recent joint work with Sofos and Teräväinen about the integral Hasse principle for random norm form equations defined over the integers.</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>    </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>';