var sms = '<div id="sms_bulletin">  <div id="sms_header">  <div class="do_not_print" id="arrow_left"><a href="?next=-3"><img src="//www2.math.ethz.ch/smsjs/images/arrow_left.png"/></a></div><div class="do_not_print" id="arrow_right"><a href="?next=-1"><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. 7</span>      <span style="float: right; text-align:right; width: 250px;">13.7 - 17.7.2026</span>      <span style="text-align: center; display: block; width: 250px; margin: auto; position: relative;">Summer Break 2026</span>    </div>  </div>  <div></div>  <div id="sms_content">    <div class="day">      <div class="day_title">        Monday, July 13      </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"> Chandrima  Kayal</div><div class="event_title">Approximate Degree Composition for Recursive Boolean Functions <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Determining the approximate degree composition for Boolean functions remains a significant open problem in Boolean function complexity. While the main problem remains unresolved, considerable progress has been made by the community toward understanding if a composition theorem holds under various structural assumptions. As a result, approximate degree composition is now known for several classes of Boolean functions. In this talk, we will see an overview of these known results and some basic techniques behind them. We will also see that approximate degree composes for a special class of inner and outer functions, namely recursive functions.</div><div class="event_time">11:00 &bull; EPF Lausanne, BC 229</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">Prof. Dr. Rico Zenklusen (ETH Z&uuml;rich, Switzerland)</div><div class="event_title">Toward Optimal Approximation Algorithms for Resource Minimization for Fire Containment on Trees and Non-Uniform k-Center <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />One of the most basic spreading models on graphs is a fire spreading from burning vertices in discrete time steps, where at each step all neighbors of burning vertices catch fire. A classical way to model fire containment is to allow for fireproofing a number $B$ of non-burning vertices at each step. Resource Minimization for Fire Containment (RMFC) asks for the smallest $B$ such that a given subset of vertices never catches fire. Even on trees, this problem is computationally hard, and prior work left a significant gap in its approximability.We close this gap by providing an optimal 2-approximation and an asymptotic PTAS, resolving two open questions. Both results follow from a unified approach: a PTAS for a smooth variant of RMFC, obtained via a careful LP-guided enumeration procedure. Building on a link between RMFC on trees and the Non-Uniform $k$-Center problem (NUkC) established by Chakrabarty, Goyal, and Krishnaswamy, our techniques yield the first approximation algorithm for NUkC that is optimal in the number of additional centers opened.Joint work with Jannis Blauth and Christian Nöbel.</div><div class="event_time">14:00 &bull; EPF Lausanne, BC 229</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Tuesday, July 14      </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"> Hyung-Chan  An</div><div class="event_title">Handling LP-Rounding for Hierarchical Clustering and Fitting Distances by Ultrametrics <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 an improved approximation algorithm for hierarchical correlation clustering. Given $L$ layers of complete graphs on a common vertex set $V$, where each edge is labeled either $+$ or $-$, the problem is to compute a clustering of $V$ for each layer so that lower-layer clusterings refine upper-layer ones and the total weighted number of disagreements over all layers is minimized. Here, a $+$ edge is counted as a disagreement if its endpoints are separated, and a $-$ edge if its endpoints are placed in the same cluster.This problem is both a natural generalization of correlation clustering (the case $L=1$) and a formulation of the $L_1$ ultrametric fitting problem arising in numerical taxonomy. Unlike the single-layer setting, for which substantial algorithmic progress has been made in recent years, the hierarchical case has seen little progress since the first constant-factor approximation algorithm of Cohen-Addad, Das, Kipouridis, Parotsidis, and Thorup. We give a new LP-rounding algorithm achieving an approximation ratio of 25.8, significantly improving the previous guarantee.Joint work with Mong-Jen Kao, Changyeol Lee, and Mu-Ting Lee (FOCS \'25).</div><div class="event_time">11:00 &bull; EPF Lausanne, BC 229</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"> Anshul Adve</div><div class="event_title">Conformal bootstrap for hyperbolic surfaces and subconvexity <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />Given a compact hyperbolic surface of fixed topology, we consider its Laplace eigenvalues together with the structure constants for multiplication with respect to a suitable orthonormal basis of automorphic forms. These numbers obey algebraic constraints analogous to the conformal bootstrap equations in physics. In this talk I will present two results. The first is a converse theorem for these constraints: any collection of numbers satisfying the constraints must come from a hyperbolic surface. The second is an application of the constraints to subconvexity for triple product L-functions. This second result is joint with James Bonifacio, Petr Kravchuk, Dalimil Mazá&#269;, Sridip Pal, Alex Radcliffe, and Gordon Rogelberg. No knowledge of physics will be assumed.</div><div class="event_time">14:15 &bull; EPF Lausanne, CM 1 517</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"> Pavel  Wiegmann (Chicago)</div><div class="event_title">Geometric deformation of Selberg integral and aspects of quantum geometry  <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />In his 1944 paper Remarks on a Multiple Integral, Atle Selberg evaluated what later became known as the Selberg integral:What happens if one deforms the support of the integral by replacing the interval [0,1] with an arbitrary Jordan arc &#947;? We show that, in the limit of a large number of variables N, the integral converges to the spectral determinant of the Laplace operator on the slit domain C\\&#947;.More generally, the Selberg integral exhibits an emergent conformal covariance under deformations of its support. This provides a probabilistic (or quantum) counterpart of Fekete\'s theory, of finite finite-dimensional approximations of conformal maps.Related works: A. Etterer, A. Zabrodin, K. Johansson, F. Viklund, K. Courteaut</div><div class="event_time">15:30 &bull; Université de Genève, Conseil Général 7-9, Room 1-07</div>        </div>      </div>    </div>    <div class="day">      <div class="day_title">        Wednesday, July 15      </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/daco-seminar">DACO Seminar</a></div><br /><div class="event_speaker">Prof. Dr. Hyung-Chan An (Yonsei University, South Korea)</div><div class="event_title">Handling LP-Rounding for Hierarchical Clustering and Fitting Distances by Ultrametrics <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 an improved approximation algorithm for hierarchical correlation clustering. Given L layers of complete graphs on a common vertex set V, where each edge is labeled either + or -, the problem is to compute a clustering of V for each layer so that lower-layer clusterings refine upper-layer ones and the total weighted number of disagreements over all layers is minimized. Here, a + edge is counted as a disagreement if its endpoints are separated, and a - edge if its endpoints are placed in the same cluster. This problem is both a natural generalization of correlation clustering (the case L=1) and a formulation of the L1 ultrametric fitting problem arising in numerical taxonomy. Unlike the single-layer setting, for which substantial algorithmic progress has been made in recent years, the hierarchical case has seen little progress since the first constant-factor approximation algorithm of Cohen-Addad, Das, Kipouridis, Parotsidis, and Thorup. We give a new LP-rounding algorithm achieving an approximation ratio of 25.8, significantly improving the previous guarantee.Joint work with Mong-Jen Kao, Changyeol Lee, and Mu-Ting Lee (FOCS \'25).</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>    </div>    <div class="day">      <div class="day_title">        Thursday, July 16      </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">        Friday, July 17      </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/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">Moduli of lattice polarized K3 surfaces <span class="abstract-button do_not_print">abstract</span></div><div class="abstract-text" style="display: none"><strong>Abstract:</strong><br />The definition of lattice polarized K3 surfaces has recently changed. I will attempt to explain the modified theory by Alexeev and Engel and its consequences with a particular focus on the intersection theory of Noether-Lefschetz cycles.</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>';