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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Federica Pasquotto <f.pasquotto@math.leidenuniv.nl><br>
<b>Date: </b>Thursday, 3 November 2022 at 12:07<br>
<b>To: </b>Federica Pasquotto <f.pasquotto@math.leidenuniv.nl><br>
<b>Subject: </b>DDT&G seminar on 18th of November: Renee Hoekzema<o:p></o:p></span></p>
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<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black">Dear all,</span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black"> </span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black">We are very pleased to announce the</span></span><span style="font-size:12.0pt;color:black"> next instalment of the Dutch Differential
Topology and Geometry seminar:<o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black"> </span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><b><span style="font-size:12.0pt;color:black">Speaker</span></b></span><span class="contentpasted0"><span style="font-size:12.0pt;color:black">: Renee Hoekzema (VU)</span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><b><span style="font-size:12.0pt;color:black">Title</span></b></span><span class="contentpasted0"><span style="font-size:12.0pt;color:black">:
<i>"</i></span></span><i><span style="font-size:11.5pt;font-family:Helvetica;color:black">Manifolds with odd Euler characteristics and higher orientability</span></i><span class="contentpasted0"><i><span style="font-size:12.0pt;font-family:"inherit",serif;color:black">"</span></i></span><i><span style="font-size:12.0pt;font-family:"inherit",serif;color:black">. </span></i><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><b><span style="font-size:12.0pt;color:black">Date</span></b></span><span class="contentpasted0"><span style="font-size:12.0pt;color:black">: Friday 18 November</span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><b><span style="font-size:12.0pt;color:black">Location</span></b></span><span class="contentpasted0"><span style="font-size:12.0pt;color:black">: Mathematical Institute, Leiden,
room 405 (Snellius building) </span></span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">Please see below for a more detailed description of the seminar's content.</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted4"><span style="font-size:12.0pt;color:black;background:white">It will also be possible to follow the seminar
<i>online</i>. T</span></span><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">he </span></span><span class="contentpasted4"><span style="font-size:12.0pt;color:black;background:white">login details will be available
soon (on the seminar's webpage and via this mailing list). </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span style="font-size:12.0pt;color:black;background:white"><o:p> </o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">We would like to remind you that master students with an interest in topology and geometry are strongly encouraged to participate.</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span style="font-size:12.0pt;color:black;background:white"> <o:p></o:p></span></p>
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<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">The schedule for all participants will be as follows:</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">2:00-3:00 p.m.: first part of the seminar (little to no prior knowledge assumed)</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">3:00-3:30 p.m.: coffee break/questions about part I</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">3:30-4:30 p.m.: second part of the seminar (slightly more advanced level)</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">4:30-...: more questions, discussion and beer </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">Please visit the seminar's webpage for additional information and an overview of past and upcoming talks:</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span style="font-size:12.0pt;color:black;background:white"><a href="https://www.few.vu.nl/~trt800/ddtg.html">https://www.few.vu.nl/~trt800/<span style="color:#070706;background:#FFEE94">ddt</span>g.html</a><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">We would also like to remind you that the previous lectures are available on the youtube channel of the seminar: </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span style="font-size:12.0pt;color:black;background:white"><a href="https://www.youtube.com/channel/UCN0o3PUqaC_ZhPNuM846kgg/" title="https://www.youtube.com/channel/UCN0o3PUqaC_ZhPNuM846kgg/">https://www.youtube.com/channel/UCN0o3PUqaC_ZhPNuM846kgg/</a><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p class="elementtoproof" style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">We hope to see many of you next week!</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">Alvaro, Federica, Rob, and Thomas.</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white"> </span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span class="contentpasted0"><b><span style="font-size:12.0pt;color:black;background:white">Abstract:
</span></b><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span class="contentpasted0"><span style="font-size:12.0pt;color:black;background:white">I will give an introduction to Steenrod squares and the classical Hopf invariant one problem. Then I will talk about a generalisation
of the classical theorem that orientable manifolds have even Euler characteristic unless the dimension is a multiple of 4. This generalization to higher orientable manifolds leads to a new open problem that extends the Hopf invariant one problem.</span></span><span style="font-size:12.0pt;color:black;background:white"><o:p></o:p></span></p>
<p style="background:white"><span style="font-size:12.0pt;color:black;background:white"><o:p> </o:p></span></p>
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