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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>INSTITUTE FOR ADVANCED STUDY<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>School of Mathematics<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>Princeton, NJ 08540<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>Mathematics Seminars<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>Week of April 23, 2018<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Times New Roman",serif'><o:p> </o:p></span></p><pre><b><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Tuesday, April 24<o:p></o:p></span></b></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'><o:p> </o:p></span></pre><pre style='margin-bottom:6.0pt'><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Joint IAS/Princeton University Number Theory Seminar<o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Topic: Algorithms for the topology of arithmetic groups and Hecke actions II<o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Speaker: Michael Lipnowski, Member, School of Mathematics<o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Time/Room: 4:45pm - 5:45pm/Simonyi Hall 101<o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'>Abstract Link: <a href="http://www.math.ias.edu/seminars/abstract?event=136742">http://www.math.ias.edu/seminars/abstract?event=136742</a><o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Times New Roman",serif'><o:p> </o:p></span></pre><p class=MsoNormal><span style='font-family:"Times New Roman",serif'>At the November workshop, I described a new algorithm to cover compact, congruence locally symmetric spaces by balls. I’ll discuss how to compute the nerve of such a covering and Hecke actions on its cohomology. Joint work with Aurel Page.At the November workshop, I described a new algorithm to cover compact, congruence locally symmetric spaces by balls. I’ll discuss how to compute the nerve of such a covering and Hecke actions on its cohomology.<br> <br>Joint work with Aurel Page.<o:p></o:p></span></p></div></body></html>