BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Emre Sertöz DTSTART:20210518T140000Z DTEND:20210518T150000Z DTSTAMP:20260423T052930Z UID:Freemath/51 DESCRIPTION:Title: Separating periods of quartic surfaces\nby Emre Sertöz as part of F ree Mathematics Seminar\n\n\nAbstract\nKontsevich--Zagier periods form a n atural number system that extends the algebraic numbers by adding constant s coming from geometry and physics. Because there are countably many perio ds\, one would expect it to be possible to compute effectively in this num ber system. This would require an effective height function and the abilit y to separate periods of bounded height\, neither of which are currently p ossible.\n\nIn this talk\, we introduce an effective height function for p eriods of quartic surfaces defined over algebraic numbers. We also determi ne the minimal distance between periods of bounded height on a single surf ace. We use these results to prove heuristic computations of Picard groups that rely on approximations of periods. Moreover\, we give explicit Liouv ille type numbers that can not be the ratio of two periods of a quartic su rface. This is joint work with Pierre Lairez (Inria\, France).\n LOCATION:https://researchseminars.org/talk/Freemath/51/ END:VEVENT END:VCALENDAR