English

The semibicategory of Moore automata

Category Theory 2023-05-02 v1 Formal Languages and Automata Theory

Abstract

We study the semibicategory Mre\textsf{Mre} of "Moore automata": an arrangement of objects, 1- and 2-cells which is inherently and irredeemably nonunital in dimension one. Between the semibicategory of Moore automata and the better behaved bicategory Mly\textsf{Mly} of "Mealy automata" a plethora of adjunctions insist: the well-known essential equivalence between the two kinds of state machines that model the definitions of Mre\textsf{Mre} and Mly\textsf{Mly} is appreciated at the categorical level, as the equivalence induced between the fixpoints of an adjunction, in fact exhibiting Mre(A,B)\textsf{Mre}(A,B) as a coreflective subcategory of Mly(A,B)\textsf{Mly}(A,B); the comodality induced by this adjunction is but the 00th step of a `level-like' filtration of the bicategory Mre\textsf{Mre} in a countable family of essential bi-localizations snMreMre\textsf{s}^n\textsf{Mre}\subseteq\textsf{Mre}. We outline a way to generate intrinsically meaningful adjunctions of this form. We mechanize some of our main results using the proof assistant Agda.

Keywords

Cite

@article{arxiv.2305.00272,
  title  = {The semibicategory of Moore automata},
  author = {Guido Boccali and Bojana Femić and Andrea Laretto and Fosco Loregian and Stefano Luneia},
  journal= {arXiv preprint arXiv:2305.00272},
  year   = {2023}
}

Comments

"The complexity of a bicategory of automata doubles every two months" (G.E.M., 1929--2023)