BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Sabre//Sabre VObject 4.6.0//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:Europe/Zurich X-LIC-LOCATION:Europe/Zurich TZURL:http://tzurl.org/zoneinfo/Europe/Zurich BEGIN:DAYLIGHT TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST DTSTART:19810329T020000 RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0200 TZOFFSETTO:+0100 TZNAME:CET DTSTART:19961027T030000 RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:news1839@dmi.unibas.ch DTSTAMP;TZID=Europe/Zurich:20250314T175051 DTSTART;TZID=Europe/Zurich:20250407T121500 SUMMARY:Bernoullis Tafelrunde: Victor Chachay (Dijon) DESCRIPTION:In algebraic geometry\, counting lines contained in surfaces is an old habit. However\, in some cases doing so for a variety defined over a non-algebraically closed field (say R instead of C) brakes a wonderful invariant result to one depending on the surface! There are some ”by han d” ways to go around this problem using geometric properties of the surf ace (apart from counting a line whenever found). We’ll see how people tr anslated these counting techniques to a more global setup (motivic homotop y and Grothendieck-Witt groups) to recover an invariant result of surfaces and (almost) fields.\\r\\nabstract [t3://file?uid=3858] X-ALT-DESC:

In algebraic geometry\, counting lines contained in surfaces is an old habit. However\, in some cases doing so for a variety defined ov er a non-algebraically closed field (say R instead of C) brakes a wonderfu l invariant result to one depending on the surface! There are some ”by h and” ways to go around this problem using geometric properties of the su rface (apart from counting a line whenever found). We’ll see how people translated these counting techniques to a more global setup (motivic homot opy and Grothendieck-Witt groups) to recover an invariant result of surfac es and (almost) fields.

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abstract< /p> DTEND;TZID=Europe/Zurich:20250407T130000 END:VEVENT END:VCALENDAR