\n
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

\n URL:/NewsandEvents/Events/Upcoming-Events/newsitem /332/2-December-2002-Finite-model-property-for-gua rded-fragments-Ian-Hodkinson END:VEVENT END:VCALENDAR