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Our main result is that if two slice knots have sufficiently different knot Floer homology, then the resulting exotic R^4's made with the simplest Casson handle are distinct. This allows us to distinguish an explicit infinite family of exotic R^4's. Our main tool is Gadgil's end Floer homology, which we compute effectively by analyzing Heegaard Floer cobordism maps. We also discuss new phenomena related to these R^4's, and relevance to the open problem of finding infinitely many smooth structures on all noncompact 4 manifolds. This is joint work with Jen Hom, Tye Lidman, and Shunyu Wan.", "occurrence_notes":null, "guid":"150488-21909511@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/150488", "building_id":"1000166", "building_name":"East Hall", "campus_maps_id":"53", "room":"3866", "location_name":"East Hall", "has_livestream":0, "cost":"", "tags":["Mathematics"], "website":"", "sponsors":[ { "group_name":"Topology Seminar - Department of Mathematics", "group_id":"4910", "website":"" }, { "group_name":"Department of Mathematics", "group_id":"3791", "website":"" } ], "image_url":"", "styled_images":{ "event_thumb":"", "event_large":"", "event_large_2x":"", "event_large_lightbox":"", "group_thumb":"", "group_thumb_square":"", "group_large":"", "group_large_lightbox":"", "event_large_crop":"", "event_list":"", "event_list_2x":"", "event_grid":"", "event_grid_2x":"", "event_feature_large":"", "event_feature_thumb":"" }, "occurrence_count":1, "first_occurrence":21909511 } , "151419-21911571": { "datetime_modified":"20260902T161740", "datetime_start":"20261009T163000", "datetime_end":"20261009T180000", "has_end_time":1, "date_start":"2026-10-09", "date_end":"2026-10-09", "time_start":"16:30:00", "time_end":"18:00:00", "time_zone":"America\/Detroit", "event_title":"2026 Faculty Mixer", "occurrence_title":"", "combined_title":"2026 Faculty Mixer", "event_subtitle":"", "event_type":"Reception \/ Open House", "event_type_id":"17", "description":"Socialize with your faculty colleagues and visit the University\u2019s famous Kelsey Museum of Archaeology during our annual Faculty Mixer event. 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