BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Lee Kennard (Syracuse University) DTSTART:20231206T160000Z DTEND:20231206T170000Z DTSTAMP:20260423T052922Z UID:VSGS/81 DESCRIPTION:Title: To rus actions with connected isotropy groups\nby Lee Kennard (Syracuse U niversity) as part of Virtual seminar on geometry with symmetries\n\n\nAbs tract\nRecent work with Michael Wiemeler and Burkhard Wilking analyzes tor us representations all of whose isotropy groups are connected. An importan t structure result is a splitting theorem\, which states that the represen tation splits as a product after passing to the induced action on a suitab le fixed-point set. More recently\, we found a connection between these re presentations and combinatorial objects called regular matroids\, and we a pplied work of Seymour to classify torus representations with connected is otropy groups. As an application\, we prove new obstructions to the existe nce of Riemannian metrics with positive sectional curvature and large symm etry. In some cases\, the assumption on the torus rank is independent of t he manifold dimension.\n LOCATION:https://researchseminars.org/talk/VSGS/81/ END:VEVENT END:VCALENDAR