{"id":1960,"date":"2021-02-24T11:09:21","date_gmt":"2021-02-24T09:09:21","guid":{"rendered":"https:\/\/mathematics.haifa.ac.il\/?p=1960"},"modified":"2021-09-12T13:11:25","modified_gmt":"2021-09-12T10:11:25","slug":"online-seminar-u-haifa-topology-geometry-seminar-on-february-25-2021","status":"publish","type":"post","link":"https:\/\/mathematics.haifa.ac.il\/?p=1960","title":{"rendered":"Online seminar, U. Haifa Topology &#038; Geometry seminar on February 25, 2021"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">A recording of the talk is available <a href=\"https:\/\/us02web.zoom.us\/rec\/share\/OLIqPAbOPdgK_4srOgXJA2SEyKW2mRpZD2EiuMWsPND9L9L909XDmLWKVaRyJc95.mWfDLCdYyt92sbQt\">here<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-44ac722c-a99b-49d8-bfbf-cdf8715ce98c\"><strong><u>Topology &amp; Geometry Seminar<\/u><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-d8ffecfd-efca-48ee-a561-bb4b86175444\">Speaker: Julie Bergner, University of Virginia<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-74bfde2b-55fc-4420-b544-d71754660b56\">Topic:&nbsp;Variants of the Waldhausen S-construction<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-95a358e5-41b2-4769-b19c-7cf9f7ae05a7\">Place:&nbsp;This is an online seminar. Please email David Blanc &#8220;blanc at math dot haifa dot ac dot il&#8221;&nbsp;for the Zoom ID and password.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-5cd19421-0a1a-4fda-b2d7-147331738d3c\">Time: 16:00<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-65971f02-2d58-4b41-987f-d2838b78f30f\">Date:&nbsp;Thursday, February 25,&nbsp;2021<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-14413b89-dac2-4325-b1f3-4bacbed2c049\">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<strong><u>Abstract<\/u><\/strong><strong><u>:<\/u><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"block-864a79d1-f3a3-46a1-913c-003b13f733c8\">The S-construction, first defined in the setting of cofibration categories by Waldhausen, gives a way to define the algebraic K-theory associated to certain kinds of categorical input.&nbsp; It was proved by Galvez-Carrillo, Kock, and Tonks that the result of applying this construction to an exact category is a decomposition space, also called a 2-Segal space, and Dyckerhoff and Kapranov independently proved the same result for the slightly more general input of proto-exact categories.&nbsp; In joint work with Osorno, Ozornova, Rovelli, and Scheimbauer, we proved that these results can be maximally generalized to the input of augmented stable double Segal spaces, so that the S-construction defines an equivalence of homotopy theories.&nbsp; In this talk, we&#8217;ll review the S-construction and the reasoning behind these stages of generalization.&nbsp; Time permitting, we&#8217;ll discuss attempts to characterize those augmented stable double Segal spaces that correspond to cyclic spaces, which is work in progress with Walker Stern.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A recording of the talk is available here. Topology &amp; Geometry Seminar Speaker: Julie Bergner, University of Virginia Topic:&nbsp;Variants of the Waldhausen S-construction Place:&nbsp;This is an online seminar. Please email David Blanc &#8220;blanc at math dot haifa dot ac dot&#8230;<br \/><a class=\"read-more-button\" href=\"https:\/\/mathematics.haifa.ac.il\/?p=1960\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,4],"tags":[],"class_list":["post-1960","post","type-post","status-publish","format-standard","hentry","category-gt-seminar","category-seminar"],"_links":{"self":[{"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/posts\/1960","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1960"}],"version-history":[{"count":2,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/posts\/1960\/revisions"}],"predecessor-version":[{"id":1962,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/posts\/1960\/revisions\/1962"}],"wp:attachment":[{"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1960"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1960"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mathematics.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1960"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}