Dualising initial algebras. Coalgebraic methods in computer science (Genova, 2001)

Neil Ghani, Christoph Lüth, Federico De Marchi, John Power

Research output: Contribution to journalArticlepeer-review

17 Citations (SciVal)


Whilst the relationship between initial algebras and monads is well understood, the relationship between final coalgebras and comonads is less well explored. This paper shows that the problem is more subtle than might appear at first glance: final coalgebras can form monads just as easily as comonads, and, dually, initial algebras form both monads and comonads.

In developing these theories we strive to provide them with an associated notion of syntax. In the case of initial algebras and monads this corresponds to the standard notion of algebraic theories consisting of signatures and equations: models of such algebraic theories are precisely the algebras of the representing monad. We attempt to emulate this result for the coalgebraic case by first defining a notion of cosignature and coequation and then proving that the models of such coalgebraic presentations are precisely the coalgebras of the representing comonad.

Original languageEnglish
Pages (from-to)349-370
Number of pages22
JournalMathematical Structures in Computer Science
Issue number2
Publication statusPublished - 2003


Dive into the research topics of 'Dualising initial algebras. Coalgebraic methods in computer science (Genova, 2001)'. Together they form a unique fingerprint.

Cite this