,
Abhisekh Sankaran
Creative Commons Attribution 4.0 International license
Seese’s conjecture for finite graphs states that monadic second-order logic (MSO) is undecidable on all graph classes of unbounded clique-width. We show that to establish this it would suffice to show that grids of unbounded size can be interpreted in two families of graph classes: minimal hereditary classes of unbounded clique-width; and antichains of unbounded clique-width under the induced subgraph relation. We explore all the currently known classes of the former category and establish that grids of unbounded size can indeed be interpreted in them.
@InProceedings{dawar_et_al:LIPIcs.CSL.2022.17,
author = {Dawar, Anuj and Sankaran, Abhisekh},
title = {{MSO Undecidability for Hereditary Classes of Unbounded Clique Width}},
booktitle = {30th EACSL Annual Conference on Computer Science Logic (CSL 2022)},
pages = {17:1--17:17},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-218-1},
ISSN = {1868-8969},
year = {2022},
volume = {216},
editor = {Manea, Florin and Simpson, Alex},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CSL.2022.17},
URN = {urn:nbn:de:0030-drops-157373},
doi = {10.4230/LIPIcs.CSL.2022.17},
annote = {Keywords: clique width, Seese’s conjecture, antichain, MSO interpretation, grid}
}