English

Duality for powerset coalgebras

Logic 2023-06-22 v6 Logic in Computer Science

Abstract

Let CABA be the category of complete and atomic boolean algebras and complete boolean homomorphisms, and let CSL be the category of complete meet-semilattices and complete meet-homomorphisms. We show that the forgetful functor from CABA to CSL has a left adjoint. This allows us to describe an endofunctor H on CABA such that the category Alg(H) of algebras for H is dually equivalent to the category Coalg(P) of coalgebras for the powerset endofunctor P on Set. As a consequence, we derive Thomason duality from Tarski duality, thus paralleling how J\'onsson-Tarski duality is derived from Stone duality.

Keywords

Cite

@article{arxiv.2008.01849,
  title  = {Duality for powerset coalgebras},
  author = {Guram Bezhanishvili and Luca Carai and Patrick Morandi},
  journal= {arXiv preprint arXiv:2008.01849},
  year   = {2023}
}
R2 v1 2026-06-23T17:38:47.557Z