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<title>Cohomology in algebra, geometry, physics and statistics</title>
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Wednesday, 25 February 2026 - 12:15 to 13:15 <br />
Place: Institute of Mathematics of ASCR, Žitná 25, Praha 1, ZOOM meeting
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Speaker: Ida Zadeh, University of Southampton, UK<br />
Title: Tracking the symmetries of Z3-orbifold K3s within the Mathieu groups
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Abstract <br />
<p>he goal of this talk is to determine the group of holomorphic symplectic automorphisms of Z3-orbifold limits of K3 surfaces, and to track this group within two of the sporadic groups Mathieu 12 and Mathieu 24. To do so, I will provide a counterpart to the extensive studies by Nikulin and others of the geometry and symmetries of classical Kummer surfaces, which involves a variation of Kondo's lattice techniques that Taormina and Wendland introduced earlier in the genesis of their symmetry surfing programme. I will realise the finite group of symplectic automorphisms of this class of K3 surfaces as a subgroup of Mathieu 12 and Mathieu 24 in terms of permutations of respectively 12 and 24 elements. The talk is based on a joint work with Kasia Budzik, Anne Taormina, Mara Ungureanu and Katrin Wendland. </p><p>+++++ </p><p>------------------------------------------------------</p><p class="ql-align-justify">This seminar starts <strong>EARLIER </strong> than the usual schedule.</p><p class="ql-align-justify"><strong style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);">We shall open the seminar room + ZOOM meeting at 12.00</strong><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);"> for (virtual) coffee and close ZOOM at 13.30</span></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);">Join Zoom Meeting</span></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><a href="https://cesnet.zoom.us/j/99598413922?pwd=YXNFbk50aVhleXhWSGtISFViLytRUT09" rel="noopener noreferrer" target="_blank" style="color: rgb(17, 85, 204); background-color: rgb(255, 255, 255);">https://cesnet.zoom.us/j/99598413922?pwd=YXNFbk50aVhleXhWSGtISFViLytRUT09</a></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);">Meeting ID:99598413922</span></p><p class="ql-align-justify"><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);">Passcode:Galois</span></p><p class="ql-align-justify"><br></p><p class="ql-align-justify">-------------------------------------------------------------------------------------</p><p class="ql-align-justify"><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);">On Wednesday March 4 </span>Andrey Krutov shall give a talk on <span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);"> </span><a href="https://www.math.cas.cz/index.php/events/event/4114" rel="noopener noreferrer" target="_blank">Non-integrable distributions with simple infinite-dimensional Lie superalgebra of symmetries </a></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34);"> </span></p><p><br></p>
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For more information see the seminar web page at <br />
https://www.math.cas.cz/index.php/events/seminar/16
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Cohomology in algebra, geometry, physics and statistics mailing list <br />
phk_seminar@math.cas.cz <br />
https://list.math.cas.cz/listinfo/phk_seminar@math.cas.cz
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