© 2002 by Oxford University Press
| ||||||||||||||||||||||||||||||||||||||||||||||||||
Original Article |
Final Coalgebras are Ideal Completions of Initial Algebras
í Adámek11 Technical University of Braunschweig, Postfach 3329, 38106 Braunschweig, Germany. E-mail: J.Adamek{at}tu-bs.de
For
-continuous endofunctors of Set an ordering of a final coalgebra T is exhibited which makes T a CPO. Moreover, an initial algebra, considered as a canonical subobject of T, hasT as its ideal completion. In more generality, for
-continuous endofunctors of locally finitely presentable categories the analogous result holds: here the ordering is considered on the hom-sets hom(B, T) for all finitely presentable objects B.
Keywords: Final coalgebra; initial algebra; complete partial order; ideal completion; algebraically complete; locally presentable category
Received September 2000.