BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250512T193836EDT-93259swm2R@132.216.98.100 DTSTAMP:20250512T233836Z DESCRIPTION:“When slow meets global: geometric insight from numerics”\n\nHi nke Osinga\, University of Auckland (joint work with José Mujica (Valparaí so) and Bernd Krauskopf (Auckland))\n\nTuesday\, September 11\, 12-1pm\n\n McIntyre Building\, Room 1027\n\nAbstract: Global manifolds are the backbo ne of a dynamical system and key to the characterisation of its behaviour. They arise in the classical sense of invariant manifolds associated with saddle-type equilibria or periodic orbits and also in the form of finite-t ime invariant manifolds in systems that evolve on multiple time scales. Th e latter are known as slow manifolds\, because the flow along such manifol ds is very slow compared with the rest of the dynamics. Slow manifolds are known to organize the number of small oscillations of so-called mixed-mod e oscillations (MMOs). Their interactions with global invariant manifolds produce complicated dynamics about which only little is known from a few e xamples in the literature. Both global and slow manifolds need to be compu ted numerically. We developed accurate numerical methods based on two-poin t boundary value problem continuation\, which have the major advantage tha t they remain well posed in parameter regimes where the time-scale separat ion varies. These techniques are particularly useful when studying changes in the global system dynamics\, such as MMOs\, global re-injection mechan isms\, transient bursting\, and phase sensitivity. This talk will focus on a transition through a quadratic tangency between the global unstable man ifold of a saddle-focus equilibrium and a repelling slow manifold in a slo w-fast system at the onset of MMO behaviour\; more precisely\, just as the equilibrium undergoes a supercritical singular Hopf bifurcation. We descr ibe the local and global properties of the manifolds\, as well as the role of the interaction as an organizer of large-amplitude oscillations in the dynamics. We find and discuss recurrent dynamics in the form of MMOs\, wh ich can be continued in parameters to Shilnikov homoclinic bifurcations.” \n DTSTART:20180911T160000Z DTEND:20180911T170000Z LOCATION:Room 1027\, McIntyre Medical Building\, CA\, QC\, Montreal\, H3G 1 Y6\, 3655 promenade Sir William Osler SUMMARY:Seminar Series in Quantitative Life Sciences and Medicine URL:/qls/channels/event/seminar-series-quantitative-li fe-sciences-and-medicine-289418 END:VEVENT END:VCALENDAR