BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//talks.cam.ac.uk//v3//EN
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
TZNAME:BST
DTSTART:19700329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
TZNAME:GMT
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CATEGORIES:Category Theory Seminar
SUMMARY: On constructing free algebras and properties of f
ree Heyting algebras - Dion Coumans\, Nijmegen\, N
etherlands
DTSTART;TZID=Europe/London:20121106T141500
DTEND;TZID=Europe/London:20121106T151500
UID:TALK40753AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/40753
DESCRIPTION:(joint work with Sam van Gool)\n\nIn this talk we
give a general method for constructing free algebr
as\, based on partial algebras. We show that\, for
certain varieties V\, the finitely generated free
V algebras may be described as the colimit of a c
hain of partial algebras that is obtained by repea
ted application of a functor. We give sufficient
conditions on V for our method to apply and use du
ality theory to show that our method applies in pa
rticular to certain classes of modal algebras.\n\n
In the second part of the talk we focus on Heyting
algebras. N. Bezhanishvilli and M. Gehrke have gi
ven a description of finitely generated free Heyti
ng algebras as a colimit of finite algebras. We di
scuss some current research that uses this descrip
tion to study properties of free Heyting algebras.
In particular\, we relate this\nconstruction to t
he universal model in intuitionistic logic.\n
LOCATION:MR5\, Centre for Mathematical Sciences
CONTACT:Julia Goedecke
END:VEVENT
END:VCALENDAR