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<title>Cohomology in algebra, geometry, physics and statistics</title>
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Wednesday, 26 February 2025 - 13:30 to 14:30 <br />
Place: Institute of Mathematics of ASCR, Žitná 25, Praha 1, the blue lecture room in the rear building + ZOOM meeting
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Speaker: Vsevolod Shevchishin, University of Warmia and Mazury at Olsztyn<br />
Title: Laemotentoma: Treating of symplectic neck stretching in symplectic 4-manifolds across Lagrangian surfaces
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Abstract <br />
<p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">Recently Borman-Li-Wu found an example of two Lagrangian embeddings</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">of the real projective plane RP^2 in a symplectic 4-manifold</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">which are Z_2-homologous but not isotopic, even smoothly.</span></p><p><br></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">In my talk I make a short introduction to the technique</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">of the symplectic neck stretching ("Laemotentoma")</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">and show how it can be used to classify Lagrangian embeddings</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">of RP^2 in symplectic 4-manifolds. In particular, I show that</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">for any given number N there exist a rational symplectic 4-manifold</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">X and Lagrangian embeddings P_1, ..., P_N of RP^2 in X</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">in the same Z_2-homology class which are pairwisely not isotopic, even smoothly.</span></p><p><span style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);">--------------------------------------------------------------------------------------------------------------------------</span></p><p><br></p><p class="ql-align-justify"><span style="color: rgb(0, 0, 255); background-color: rgb(246, 246, 246);" class="ql-font-monospace">We shall open the seminar room at 13.15 for coffee and close the room at 15:00</span></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="color: rgb(0, 0, 255); background-color: rgb(246, 246, 246);" class="ql-font-monospace">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=YXNFbk50aVhleXhWSGtISFViLytRU9" rel="noopener noreferrer" target="_blank" style="background-color: transparent; color: rgb(0, 0, 204);" class="ql-font-monospace">https://cesnet.zoom.us/j/99598413922?pwd=YXNFbk50aVhleXhWSGtISFViLytRU9</a></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="color: rgb(0, 0, 255); background-color: rgb(246, 246, 246);" class="ql-font-monospace">MeetingID:99598413922</span></p><p class="ql-align-justify"><br></p><p class="ql-align-justify"><span style="color: rgb(0, 0, 255); background-color: rgb(246, 246, 246);" class="ql-font-monospace">Passcode:Galois</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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