BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//pretalx//pretalx.c3voc.de//qtcat-2026//speaker//LHJKNK
BEGIN:VTIMEZONE
TZID:CET
BEGIN:STANDARD
DTSTART:20001029T040000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:CET
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:20000326T030000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3
TZNAME:CEST
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
END:DAYLIGHT
END:VTIMEZONE
BEGIN:VEVENT
UID:pretalx-qtcat-2026-SBZJVC@pretalx.c3voc.de
DTSTART;TZID=CET:20260812T120000
DTEND;TZID=CET:20260812T123000
DESCRIPTION:Consider the category of groups with its forgetful functor down
  to Set. This functor is monadic\, which tells us that groups are sets equ
 ipped with an algebraic structure. Now consider the category of finite set
 s\, with its inclusion into Set. This functor is not monadic for many reas
 ons\, but what monadic functor best approximates it? In other words\, fini
 te sets are most like sets equipped with what algebraic structure? The ans
 wer to this question is given my the codensity monad of FinSet -> Set. Qui
 te surprisingly\, this is the ultrafilter monad\, whose algebras are compa
 ct Hausdorff spaces!\n\nThat's all well an good\, but why should you care?
  Every monad is trivially the codensity monad of some functor. Does it mat
 ter if it is the codensity monad of a specially nice one\, say a fully fai
 thful one? It does! For example\, if a polynomial monad T on Set restricts
  to FinSet\, then a general theory guarantees that there is a unique distr
 ibutive law of the ultrafilter monad over T\, i.e. a unique monad on CHaus
  which lifts T.\n\nIn this talk I will tell you about this recent developm
 ent about distributive laws involving codensity monads\, and how they rela
 te to the main subject of my thesis: pushforward monads. We will use the u
 lftrafilter monad as our central example.
DTSTAMP:20260812T202107Z
LOCATION:R. 221
SUMMARY:Who cares about codensity monads? - Adrián Doña Mateo
URL:https://pretalx.c3voc.de/qtcat-2026/talk/SBZJVC/
END:VEVENT
END:VCALENDAR