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. 15</span>      <span style="float: right; text-align:right; width: 250px;">25.5 - 29.5.2026</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Spring Semester 2026</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, May 25      </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 26      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_ba"><a class="external" href="https://unibas.ch">Universität Basel</a></div><div class="event_type"><a class="external" href="https://dmi.unibas.ch/de/forschung/mathematik/algebraische-geometrie/">Seminar Algebra and Geometry</a></div><br /><div class="event_speaker"> Wendelin Lutz (Universität Hannover)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/seminar-algebra-and-geometry-wendelin-lutz-universitaet-hannover/">The Morrison Cone Conjecture under deformation.</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Let Y be a Calabi--Yau variety. The Morrison Cone Conjecture is a fundamental conjecture in Algebraic Geometry on the geometry of the nef cone and the movable cone of Y: while these cones are usually not rational polyhedral, the cone conjecture predicts that the action of Aut(Y) on Nef(Y) admits a rational polyhedral fundamental domain, and that the action of Bir(Y) on Mov(Y) admits a rational polyhedral fundamental domain. Even though the conjecture has been settled in special cases, it is still wide open in dimension at least 3. We prove that if the cone conjecture holds for a smooth Calabi-Yau threefold Y, then it also holds for any smooth deformation of Y.  If time permits, I will explain how to generalize some of the ideas to the case of log Calabi-Yau varieties.</div><div class="event_time">10:30 &bull; Universität Basel, Spiegelgasse 5, Seminarraum 05.002</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_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"> Mikael  de la Salle (Université de Lyon I)</div><div class="event_title">Ensembles de Kakeya et algèbres de von Neumann de groupes arithmétiques <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Les ensembles de Kakeya sont des sous-ensembles de l\'espace euclidien contenant un segment unité dans chaque direction. Ils constituent un sujet d\'étude fascinant en mathématiques récréatives, mais depuis les travaux fondateurs de Fefferman sur la convergence des séries de Fourier, ils ont trouvé d\'importantes applications en mathématiques sérieuses : analyse harmonique, théorie des nombres. Je présenterai un lien récemment découvert avec les algèbres d\'opérateurs, et plus précisément avec la structure des algèbres de von Neumann des groupes arithmétiques de rang supérieur.</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_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"> Ander  Murua Uria (Universiy san Sebastian)</div><div class="event_title">SIMD-vectorized implicit symplectic integrators can outperform explicit symplectic ones</div><div class="event_time">14:00 &bull; Université de Genève, Conseil Général 7-9, Room 1-05</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_dis"><a class="external" href="https://unidistance.ch">UniDistance Suisse</a></div><div class="event_type"><a class="external" href="https://unidistance.ch/en/mathematiques-et-informatique/recherche/number-theory/number-theory-seminar">Number Theory Seminar</a></div><br /><div class="event_speaker"> Johannes  Girsch  (Durham University)</div><div class="event_title">Langlands-Shahidi gamma factors and local transfer in families <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The Langlands–Shahidi method provides a powerful framework for constructing gamma factors associated with generic representations of reductive p-adic groups in a wide range of cases. In this talk, I will explain how this construction extends to the setting of algebraic families and discuss how this leads to a local transfer map in families. As an application, we recover a special case of recent results Alberto Minguez and Vincent Secherre. This is joint work with Robert Kurinczuk.</div><div class="event_time">15:00 &bull; <a class="external" href="https://tinyurl.com/UniDistanceNTSeminar">UniDistance Suisse, Zoom</a></div>        </div>        <div class="day_content_item normal"><div class="event_location uni_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"> Andras Szenes (UNIGE)</div><div class="event_title">Enumerative P=W and the Bethe Ansatz  <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />I will describe joint work with Sh. Shakirov relating the P=W conjecture for the moduli of Higgs bundles to the enumerative invariants of these spaces, on the one hand, and to special solutions of the Bethe equations on the other.</div><div class="event_time">15:00 &bull; Université de Genève, Conseil Général 7-9, Room 1-07</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://uzh.ch">Universit&auml;t Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/s/zurich-colloquium-in-mathematics">Zurich Colloquium in Mathematics</a></div><br /><div class="event_speaker"> Lisa Piccirillo (University of Texas at Austin)</div><div class="event_title">Exotic phenomena in 4-manifold topology</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, May 27      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_ba"><a class="external" href="https://unibas.ch">Universität Basel</a></div><div class="event_type"><a class="external" href="https://dmi.unibas.ch/de/forschung/mathematik/zahlentheorie/">Seminar Zahlentheorie</a></div><br /><div class="event_speaker"> Vesselin Dimitrov (Caltech)</div><div class="event_title"><a class="external" href="https://dmi.unibas.ch/de/news-events/detail/number-theory-seminar-vesselin-dimitrov-caltech/">Title T.B.A.</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Title: Arithmetic holonomy bounds in transcendence proofs and effective Diophantine approximation. Abstract: The method of arithmetic holonomy bounds, developed presently in a collaboration with Calegari and Tang, encodes some Diophantine problems of a traditional interest into suitable generating functions with good analytic and Diophantine properties. I will present a completely explicit Ansatz and explain its fairly straightforward proof. The challenge is then to cook up holonomy template setups where the Ansatz has interesting consequences. Nevertheless, already the simplest "infinite dihedral orbifold" setup has applications including the transcendence of Pi (in a particularly simple way) and a new effective solution of the two-variable S-unit equation, but also some explicit irrationality measures for logarithms that seem to enter into a blind spot of the literature. New room: Seminarraum 00.002, Rheinsprung 21</div><div class="event_time">10:15 &bull; Universität Basel</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_la"><a class="external" href="https://www.epfl.ch">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"> Prashanth  Amireddy</div><div class="event_title">Title T.B.A. <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The PCP Theorem is a central result in theoretical computer science giving query-efficient verifiers for NP. All known proofs of the PCP Theorem rely on (multiple applications of) proof composition, where two sub-optimal PCPs are combined into an optimal one. In this work, we build improved component PCPs strong enough that only a single composition step is needed to recover the PCP Theorem. In particular, we give a new and direct construction (i.e., without composition) of a constant-query PCP with proof size 2^{n^&#949;} for arbitrarily small constant &#949; > 0, which is a regime of parameters evaded by prior constructions.Our constructions are based on a new Zero-on-Variety Test for checking whether an oracle f : F^m &#8594; F is identically zero on a variety V &#8838; F^m (where F is a finite field). While previous works largely tackle this problem for the setting of V = H^m (a product set), our test applies to much more general varieties, with proof size governed by a measure known as the Macaulay basis complexity of the variety. Instantiating this framework with two specific varieties and composing the resulting PCPs thus yields a proof of the PCP Theorem with a single  composition. Joint work with Amik Raj Behera, Srikanth Srinivasan, Madhu Sudan, and Sophus Valentin Willumsgaard.</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://www.math.uzh.ch/mat760">Ergodic theory and dynamical systems seminar</a></div><br /><div class="event_speaker">Prof. Dr. Dimitry Dolgopyat (University of Maryland)</div><div class="event_title">Up the Down Staircase <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">We describe generic points for linear flows with bounded &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">type slope on the &nbsp;infinite staircase. &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">As an application we characterize bounded type rotation numbers for &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">which the error terms for Kronicker discrepancy &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">are uniformly distributed. A key step in our proof is the local limit &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">theorem for inhomogeneous Markov chains &lt;/span>&lt;span style="caret-color: #ffffff; color: #000000; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline !important; float: none;">in the regime of large deviations. Based on a joint work with Omri Sarig.&lt;/span>&lt;/p></div><div class="event_time">13:30 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 19.1</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ne"><a class="external" href="https://unine.ch">Universit&auml;t Neuchatel</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">Chiara Spadafora (Swiss Post)</div><div class="event_title">From Theory to Deployment: Insights from the Swiss Post E-Voting Protocol <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>How do cryptography and real-world constraints meet in an e-voting system? This talk examines how cryptographic protocols are translated into a real-world e-voting system, involving legal requirements, operational procedures, and human factors. The main focus of the talk is the e-voting protocol currently deployed by some Swiss cantons to enable citizens to securely cast their votes online in legally binding elections. We then move from the present to the near future, detailing the new protocol under development and highlighting how it is expected to improve both the security and the verifiability of the system.<br>Throughout the talk, we keep an eye on practical constraints: how the Federal Ordinance on electronic voting shapes trust assumptions and transparency requirements, and how operational procedures influence the generation of election parameters and the verification of protocol steps. We also address usability and accessibility, discussing how the voting process can be made understandable and verifiable for all voters. We close by outlining how external experts and independent implementations contribute to the continuous evaluation and analysis of the protocol.&lt;/p></div><div class="event_time">15:00 &bull; Uni Neuchatel, B217</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"> Francesco Lin (Columbia University)</div><div class="event_title">Coexact 1-form spectral gaps and three-dimensional topology <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The spectral gap of the Hodge Laplacian on coexact 1-forms is a fundamental quantity associated to a Riemannian manifold which has attracted quite a lot of attention in recent years. I will begin by discussing the role it plays in topological problems about three-manifolds (such as the existence on taut foliations on rational homology spheres) via its relation with Floer theoretic invariants. Motivated by this, I will then focus on the case of hyperbolic manifolds, and describe techniques to determine explicitly such spectral gaps in concrete examples (including certain infinite families). This is joint work with M. Lipnowski.</div><div class="event_time">15:30 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_be"><a class="external" href="https://www.unibe.ch">Universität Bern</a></div><div class="event_type"><a class="external" href="https://www.imsv.unibe.ch/research/talks/colloquia/index_eng.html">Colloquia on Probability and Statistics </a></div><br /><div class="event_speaker">Prof. Dr. Aymeric Dieuleveut (Ecole Polytechnique)</div><div class="event_title"><a class="external" href="https://www.imsv.unibe.ch/research/talks/schedule/index_eng.html">Computer-aided proofs in first-order optimization, with applications to error feedback</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />First-order methods are widely used in optimization and machine learning, and their behavior is often analyzed through the spectrum of worst case convergence rates. Obtaining such guarantees is often difficult and both time consuming and error-prone. Starting with the work of Drori and Teboulle (2014), novel techniques have been used to gain numerical insights, leading to the release of various performance estimation (PE) software. In this talk, I will show how various computer-aided techniques can be used to study first-order optimization methods in a systematic way. From performance estimation problems with automated Lyapunov discovery, to symbolic regression and computer algebra systems, novel tools completely reshape the way we approach theory of optimization. As a main example, I will focus on error feedback methods used with compressed communication in distributed optimization. While error feedback has been widely studied, existing theory often provides untight (thus unreliable)  bounds. I will present tight analyses with matching lower bounds that allow a fair comparison between error feedback schemes and standard compressed gradient descent, and help explain when error feedback is useful and when it is not.Overall, the talk aims to show how various computer-aided proofs can lead to clearer and more reliable insights into first-order optimization methods.</div><div class="event_time">16:15 &bull; Universität Bern, Hörsaal B78, ExWi, Sidlerstrasse 5, 3012 Bern</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_ne"><a class="external" href="https://unine.ch">Universit&auml;t Neuchatel</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">Michele Battagliola (Universität St.Gallen)</div><div class="event_title">The Code Equivalence Problem in Cryptography <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />&lt;p>Given two linear codes, the Code Equivalence Problem asks to find (if it exists) an isometry between them. In this talk we introduce linear code equivalence and its main variants (permutation, monomial). We then discuss its crucial role as a hardness assumption in post-quantum digital signatures, with particular focus on LESS and related schemes, such as LEAST. Finally, we present new cryptanalysis techniques based on power codes that efficiently solve permutation and linear code equivalence for low dimension codes.&lt;/p></div><div class="event_time">16:30 &bull; Uni Neuchatel, B217</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Thursday, May 28      </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">EPFL Lausanne</a></div><div class="event_type"><a class="external" href="https://www.epfl.ch/labs/hessbellwald-lab/epfl-topology-seminar-spring-2026/">Séminaire de Topologie </a></div><br /><div class="event_speaker"> Kate Benjamin (University of Oxford)</div><div class="event_title"><a class="external" href="https://www.epfl.ch/labs/hessbellwald-lab/epfl-topology-seminar-spring-2026/">Topology of spatiotemporal trajectories</a> <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In recent years, multiparameter persistent homology (MPH) has been developed to address the limitations of traditional single-parameter persistence. While much progress has been made on the theoretical aspects of MPH, practical applications have mostly been limited to the special case of two parameters. Building on recent developments in the computation of MPH in more than two parameters, we propose and implement a new algorithm for the computation of multiparameter persistence landscapes in this setting. We apply this work to compute landscapes of three-parameter persistence modules built on spatiotemporal data arising in biology.</div><div class="event_time">10:00 &bull; <a class="external" href="https://plan.epfl.ch/?room==CM%201%20517">EPFL Lausanne</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/fim/activities/nachdiplom-lectures">Nachdiplomvorlesung</a></div><br /><div class="event_speaker"> Sylvain Crovisier (Université Paris-Saclay)</div><div class="event_title">Ergodic theory of surface diffeomorphisms</div><div class="event_time">10:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_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"> Jorge Becerra (Dijon)</div><div class="event_title">Title T.B.A.</div><div class="event_time">14:15 &bull; Université de Genève, Conseil Général 7-9, 1-15</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">ZueKoSt: Seminar on Applied Statistics</a></div><br /><div class="event_speaker"> Guillaume Lecué (ESSEC Business School, Cergy, France)</div><div class="event_title">On the feature space decomposition of several estimators <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 a methodology called the feature space decomposition and apply it to the statistical analysis of several estimators such as min ell2 norm interpolant estimators,  ridge estimators, spectral methods, minimum ellq-norm interpolant estimators and max-margin classifiers.We  establish high-probability non-asymptotic upper bounds for the excess risk of these estimators. In the case of min ell2 norm interpolant estimators,  ridge estimators and spectral methods, we show that these bounds are sharp. In particular, we obtain necessary and sufficient conditions for benign overfitting behavior of the min ell2 norm interpolant estimators.Our results rely on a method called feature space decomposition where the self-regularization properties of minimum norm interpolant estimator is highlighted. Technically, we circumvent tools such as the convex min-max theorem, instead employing tools from Geometric Aspects of Functional Analysis, in particular, the Dvoretzky-Milman theorem plays a central role in our analysis. This provides a geometric perspective on benign overfitting, and crucially, our techniques remain valid beyond the Gaussian case. Consequently, we obtain benign overfitting results with high probability when the design vector is not necessarily Gaussian.We particularly emphasize that the feature space decomposition  method may potentially refine the uniform convergence approach, suggesting its promise as a new methodology in mathematical statistics.Based on joint works with Radoslaw Adamczak, George Gavrilopoulos, Zhifan Li, Zong Shang and Marta Strzelecka.</div><div class="event_time">16:15 &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://stat.ethz.ch/events/research_seminar">Research Seminar in Statistics</a></div><br /><div class="event_speaker"> Guillaume  Lecué (ESSEC Business School, Cergy, France)</div><div class="event_title">On the feature space decomposition of several estimators <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 a methodology called the feature space decomposition and apply it to the statistical analysis of several estimators such as min ell2 norm interpolant estimators, ridge estimators, spectral methods, minimum ellq-norm interpolant estimators and max-margin classifiers. We establish high-probability non-asymptotic upper bounds for the excess risk of these estimators. In the case of min ell2 norm interpolant estimators, ridge estimators and spectral methods, we show that these bounds are sharp. In particular, we obtain necessary and sufficient conditions for benign overfitting behavior of the min ell2 norm interpolant estimators. Our results rely on a method called feature space decomposition where the self-regularization properties of minimum norm interpolant estimator is highlighted. Technically, we circumvent tools such as the convex min-max theorem, instead employing tools from Geometric Aspects of Functional Analysis, in particular, the Dvoretzky-Milman theorem plays a central role in our analysis. This provides a geometric perspective on benign overfitting, and crucially, our techniques remain valid beyond the Gaussian case. Consequently, we obtain benign overfitting results with high probability when the design vector is not necessarily Gaussian. We particularly emphasize that the feature space decomposition method may potentially refine the uniform convergence approach, suggesting its promise as a new methodology in mathematical statistics. Based on joint works with Radoslaw Adamczak, George Gavrilopoulos, Zhifan Li, Zong Shang and Marta Strzelecka.</div><div class="event_time">16:15 &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">Prof. Dr. Nina Gantert (Technical University of Munich)</div><div class="event_title">Consensus and Disagreement in Opinion Dynamics <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />We explain some models coming from mathematical modelling of social interactions. In these models, vertices of a graph hold an opinion, taking for instance values in [0,1], and interact with their neighbours provided that the opinions they hold do not differ too much. We give some results and present open conjectures for one of these models, namely the Deffuant model. We then give some rigorous results for two variants, namely the compass model and the averaging process. The results are based on joint works with Markus Heydenreich and Timo Vilkas. No prerequisites will be assumed.</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, May 29      </div>      <div class="day_content">        <div class="day_content_item normal"><div class="event_location uni_zh"><a class="external" href="https://ethz.ch">ETH Z&uuml;rich</a></div><div class="event_type"><a class="external" href="https://math.ethz.ch/fim/activities/nachdiplom-lectures">Nachdiplomvorlesung</a></div><br /><div class="event_speaker"> Tom Hutchcroft (California Institute of Technology (Caltech))</div><div class="event_title">Dimension dependence of critical phenomena in percolation</div><div class="event_time">10:15 &bull; ETH Zentrum, R&auml;mistrasse 101, Z&uuml;rich, Building HG, Room G 43</div>        </div>        <div class="day_content_item normal"><div class="event_location uni_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. Vladimir Dokchitser (UCL)</div><div class="event_title">Reduction types of curves of genus 2 <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />During the days of early experiments on the Birch--Swinnerton-Dyer conjecture, Tate produced a table for elliptic curves over p-adic fields that beautifully summarises their arithmetic invariants. I will present an analogous set of tables for curves of genus 2. The invariants addressed include: reduction type of the minimal regular model, Neron component group of the Jacobian, conductor exponent, and the valuation of the discriminant of a minimal Weierstrass model. This is joint work with Edwina Aylward, Lilybelle Cowland Kellock and Elvira Lupoian.</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>';