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<p class="MsoNormal"><span lang="EN-US">Dear all,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This Tuesday at 11:00 we have a new session of the reading seminar on Diffeomorphism Groups. Rolf and Deborah will present the general strategy to prove the perfectness and the simplicity of Diffeomorphism Groups, based
on Chapter 2 of Banyaga’s book.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I collected in a dropbox folder some material about the first talk given by Albert and I<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://www.dropbox.com/scl/fo/u3vp4q6hqb7e70zbd8keo/AJdmY2gCOwnGQwI94ZOylII?rlkey=7nfhmvnmmcmrsisn6msr7bcq3&st=rfav0ezc&dl=0">https://www.dropbox.com/scl/fo/u3vp4q6hqb7e70zbd8keo/AJdmY2gCOwnGQwI94ZOylII?rlkey=7nfhmvnmmcmrsisn6msr7bcq3&st=rfav0ezc&dl=0</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This includes notes and videos introducing diffeomorphism groups and looking at their Lie Algebras. In particular, Theorem 1.4.3 (Chapter 1, Banyaga) gives the infinitesimal perfectness at the level of Lie Algebras. The
proof of Theorem contains an instructive mistake (can you find where?) inherited by Omori’s book. In the notes, you find the correct proof taken from a paper by Lichnerowitz (also in the dropbox folder).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">See you on Tuesday either in NU-09A46 or online at<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://vu-live.zoom.us/j/99134747510?pwd=5by9w5TVDWVlnLEkXxaAcdwPRfPw4j.1">https://<span lang="en-NL">vu-live.zoom.us/j/99134747510?pwd=5by9w5TVDWVlnLEkXxaAcdwPRfPw4j.1</span></a></span><span lang="EN-US">
</span><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Have a good start of the week!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Gabriele<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://www.few.vu.nl/~trt800/arbeitsgemeinschaft.html">https://www.few.vu.nl/~trt800/arbeitsgemeinschaft.html</a><o:p></o:p></span></p>
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