BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Igor Khavkine (Czech Academy of Sciences) DTSTART:20211020T162000Z DTEND:20211020T180000Z DTSTAMP:20260423T023043Z UID:GDEq/44 DESCRIPTION:Title: Tr iangular decoupling of systems of differential equations\, with applicatio n to separation of variables on Schwarzschild spacetime\nby Igor Khavk ine (Czech Academy of Sciences) as part of Geometry of differential equati ons seminar\n\n\nAbstract\nCertain tensor wave equations admit a complete separation of variables on the Schwarzschild spacetime (asymptotically fla t\, static\, spherically symmetric black hole in 4d)\, resulting in compli cated systems of radial mode ODEs. Almost none of the important questions about these radial mode equations can be answered in their original form. I will discuss a drastic simplification of these ODE systems to sparse upp er triangular form\, which uncovers their general properties. Essential to this simplification are geometric properties of the original tensor wave equations\, ideas from homological algebra and from the theory of ODEs wit h rational coefficients. Based on https://arxiv.org/abs/1711.00585 \, http s://arxiv.org/abs/1801.09800 \, https://arxiv.org/abs/2004.09651\n LOCATION:https://researchseminars.org/talk/GDEq/44/ END:VEVENT END:VCALENDAR