BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250531T144354EDT-4680UCeoNe@132.216.98.100 DTSTAMP:20250531T184354Z DESCRIPTION:Title: Propagation of coherent states and problems of conical i ntersections\n\nAbstract: \n\nIn this talk\, we will study the propagation of coherent states (or wavepackets) for a system of coupled Schr枚dinger e quations\, in the semi-classical limit.\n These equations appear in Quantum Chemistry to describe large molecules - namely with a very small electron ic mass / nucleus mass ratio (semi-classical parameter).\n The coupling bet ween these equations can generate interesting phenomena: the Born-Oppenhei mer Approximation is not valid anymore and transitions between energy leve ls can occur.\n Usually\, these couplings are induced by a matrix-valued po tential with 'eigenvalue crossings': they are equal on some region of the phase space.\n We will focus on a precise question about the stability of t he solution. Consider an initial coherent state (one can think of a gaussi an)\, well-localized in phase space\, 'living' in a chosen eigenspace of t he potential (ie at some given energy level). Does the associated solution keep the same localization property at leading order and does it stay in the same eigenspace (adiabaticity) ?\n Without technical details\, we will study various situations for several types of crossings leading to transit ion phenomena.\n\nWhere: Pavillion Andr茅-Aisenstadt\, room 5183\, and by Z oom (see link below)\n\nJoin Zoom Meeting\n\nhttps://umontreal.zoom.us/j/8 9528730384?pwd=IF10Cg8C0YfogaBlL6F1NboPaQvAaV.1\n\nMeeting ID: 895 2873 03 84\n\nPasscode: 077937\n DTSTART:20250212T191500Z DTEND:20250212T201500Z SUMMARY:Lysianne Hari (Universit茅 Marie et Louis Pasteur) URL:/mathstat/channels/event/lysianne-hari-universite- marie-et-louis-pasteur-363606 END:VEVENT END:VCALENDAR