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Tuesday, 21 May 2024 - 10:00 to 11:30 <br />
Place: IM, konírna
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Speaker: Matěj Konečný, TU Dresden<br />
Title: On binary symmetric homogeneous structures
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Abstract <br />
<p><br></p><p> A majority of the known examples of non-free strong amalgamation classes are in binary symmetric languages (various metric spaces, metrically homogeneous graphs, ultrametrics, lambda-ultrametrics, the 5-cycle, etc.). In most cases there is a family F of edge-labelled cycles and cliques such that an edge-labelled graph G has a homomorphism to the Fraisse limit if and only if no member of F has a homomorphism to G; understanding F is then a key ingredient for proving EPPA, or finding a Ramsey expansion. In this work-in-progress (joint with Manuel Bodirsky and Honza Hubička) we study such cycle-clique-constrained binary symmetric classes. I will report on what we have and prove some fun facts which one can prove given these assumptions. The talk will be self-contained and I will try to give many examples.</p>
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For more information see the seminar web page at <br />
https://www.math.cas.cz/index.php/events/seminar/6
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Set Theory and Analysis mailing list <br />
settfa@math.cas.cz <br />
https://list.math.cas.cz/listinfo/settfa@math.cas.cz
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