BEGIN:VCALENDAR VERSION:2.0 PRODID:ILLC Website X-WR-TIMEZONE:Europe/Amsterdam BEGIN:VTIMEZONE TZID:Europe/Amsterdam X-LIC-LOCATION:Europe/Amsterdam BEGIN:DAYLIGHT TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST DTSTART:19700329T020000 RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0200 TZOFFSETTO:+0100 TZNAME:CET DTSTART:19701025T030000 RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:/NewsandEvents/Archives/2002/newsitem/332/2-De cember-2002-Finite-model-property-for-guarded-frag ments-Ian-Hodkinson DTSTAMP:20021128T000000 SUMMARY:Finite model property for guarded fragment s, Ian Hodkinson ATTENDEE;ROLE=Speaker:Ian Hodkinson DTSTART;TZID=Europe/Amsterdam:20021202T151500 DTEND;TZID=Europe/Amsterdam:20021202T000000 LOCATION:P.016, Euclides, Plantage Muidergracht 24 , Amsterdam DESCRIPTION:Abstract: Guarded fragments are in so me sense `modal-style' fragments of first-order lo gic. Introduced by Andréka, van Benthem and Németi in 1997, they have become very popular. They shar e nice properties with modal logic, such as decida bility with reasonable complexity. The finite mode l property for the basic guarded fragment was esta blished by Erich Grädel in 1999. Since then, sever al more results for stronger fragments have been p roved. The proofs use a combinatorial theorem of H erwig, and recently this theorem has been strength ened in joint work with Martin Otto, permitting a simpler proof that the loosely guarded and packed (or clique-guarded) fragments have the finite mode l property. I will outline some of the ideas and h istory of this area of research. For more infor mation, contact Yde Venema (yde at science.uva.nl) X-ALT-DESC;FMTTYPE=text/html:\n
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Abstract:
\n Guarded fragments are
in some sense `modal-style'\n fragment
s of first-order logic. Introduced by\n
Andréka, van Benthem and Németi in
1997,\n they have become very popular.
They share nice properties\n with mod
al logic, such as decidability with reasonable\n
complexity. The finite model property f
or the basic\n guarded fragment was est
ablished by Erich Grädel in\n 1999
. Since then, several more results for stronger\n
fragments have been proved. The proof
s use a\n combinatorial theorem of Herw
ig, and recently this theorem\n has bee
n strengthened in joint work with Martin Otto,\n
permitting a simpler proof that the loos
ely guarded and\n packed (or clique-gua
rded) fragments have the finite model\n
property. I will outline some of the ideas and h
istory of\n this area of research.\n
\n For more informa tion, contact Yde Venema\n (yde at science.uva.nl)\n
URL:/NewsandEvents/Archives/2002/newsitem/332/2-De cember-2002-Finite-model-property-for-guarded-frag ments-Ian-Hodkinson END:VEVENT END:VCALENDAR