BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Li Ling Ko (University of Notre Dame) DTSTART:20201027T200000Z DTEND:20201027T210000Z DTSTAMP:20260423T004823Z UID:CTA/26 DESCRIPTION:Title: Fic kleness and bounding lattices in the recursively enumerable Turing degrees \nby Li Ling Ko (University of Notre Dame) as part of Computability th eory and applications\n\n\nAbstract\nThe ability for a recursively enumera ble Turing degree $d$ to bound certain\nimportant lattices depends on the degree's fickleness. For instance\, $d$\nbounds $L_7$ (1-3-1) if and only if $d$'s fickleness is $>\\omega$\n($\\geq\\omega^\\omega$). We work towar ds finding a lattice that characterizes\nthe $>\\omega^2$ levels of fickle ness and seek to understand the challenges\nfaced in finding such a lattic e. The candidate lattices considered include\nthose that are generated fro m three independent points\, and upper\nsemilattices that are obtained by removing the meets from important\nlattices.\n LOCATION:https://researchseminars.org/talk/CTA/26/ END:VEVENT END:VCALENDAR