BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Maik Gröger DTSTART:20210319T091500Z DTEND:20210319T104500Z DTSTAMP:20260423T021930Z UID:DSSUJ/25 DESCRIPTION:Title: G roup actions with discrete spectrum and their amorphic complexity\nby Maik Gröger as part of Dynamical systems seminar at the Jagiellonian Univ ersity\n\nLecture held in 1016.\n\nAbstract\nAmorphic complexity\, origina lly introduced for integer actions\, is a\ntopological invariant which mea sures the complexity of dynamical\nsystems in the regime of zero entropy.\ nWe will explain its definition for actions by locally compact\nsigma-comp act amenable groups on compact metric spaces.\nAfterwards\, we will illust rate some of its basic properties and show\nwhy it is tailor-made to study strictly ergodic group actions with\ndiscrete spectrum and continuous eig enfunctions.\nThis class of actions includes\, in particular\, Delone dyna mical\nsystems related to regular model sets obtained via cut and project\ nschemes (CPS).\nFinally\, for this family of Delone dynamical systems we present sharp\nupper bounds on amorphic complexity utilizing basic propert ies of the\ncorresponding CPS.\nThis is joint work with G. Fuhrmann\, T. J äger and D. Kwietniak.\n LOCATION:https://researchseminars.org/talk/DSSUJ/25/ END:VEVENT END:VCALENDAR