,
Stefan Milius
,
Henning Urbat
Creative Commons Attribution 4.0 International license
We propose a novel topological perspective on data languages recognizable by orbit-finite nominal monoids. For this purpose, we introduce pro-orbit-finite nominal topological spaces. Assuming globally bounded support sizes, they coincide with nominal Stone spaces and are shown to be dually equivalent to a subcategory of nominal boolean algebras. Recognizable data languages are characterized as topologically clopen sets of pro-orbit-finite words. In addition, we explore the expressive power of pro-orbit-finite equations by establishing a nominal version of Reiterman’s pseudovariety theorem.
@InProceedings{birkmann_et_al:LIPIcs.ICALP.2023.114,
author = {Birkmann, Fabian and Milius, Stefan and Urbat, Henning},
title = {{Nominal Topology for Data Languages}},
booktitle = {50th International Colloquium on Automata, Languages, and Programming (ICALP 2023)},
pages = {114:1--114:21},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-278-5},
ISSN = {1868-8969},
year = {2023},
volume = {261},
editor = {Etessami, Kousha and Feige, Uriel and Puppis, Gabriele},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ICALP.2023.114},
URN = {urn:nbn:de:0030-drops-181662},
doi = {10.4230/LIPIcs.ICALP.2023.114},
annote = {Keywords: Nominal sets, Stone duality, Profinite space, Data languages}
}