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Herlihy and Shavit [Herlihy and Shavit, 1999], Saks and Zaharoglou [M. Saks and F. Zaharoglou, 2000], building on the work of Borowsky and Gafni [Borowsky and Gafni, 1997], have shown that questions of distributed computability were amenable to a topological approach by encoding distributed systems as simplicial complexes. We present an extension of the simplicial semantics for distributed computing by identifying spectral topology as a natural generalization thereof. In particular, we extend the topological approach of the Asynchronous Computability Theorem to any round-based, content-neutral, full-information protocol, a family of models containing the Iterated Immediate Snapshot protocol. The main insight of this work is in considering global states obtained after finite executions of a distributed protocol Π not as abstract simplicial complexes as was previously done, but as finite posets. This extension enables us to prove a new general distributed computability theorem : a protocol Π solves a colorless task (ℐ,𝒪,Δ) if and only if there exists a spectral map f:Π^∞(ℐ) → 𝒪 compatible with Δ, where Π^∞(ℐ) is a spectral space associated to the protocol Π. This space is introduced in this work. From this general characterization, many known colorless computability theorems can be directly derived. In particular, we provide new insights into the previously established connection between colorless task-solvability and continuous maps between geometric realizations. Our proofs rely on Stone duality, a well established tool in semantics theory which links spectral spaces with distributive lattices. In this semantics, spaces correspond to program behaviours and lattices to program specifications, related by a crucial "ingredient" (see [Mai Gehrke, 2016]), namely topology.
@InProceedings{calk_et_al:LIPIcs.DISC.2026.61,
author = {Calk, Cameron and Godard, Emmanuel},
title = {{Brief Announcement: Stone Duality Proofs for Colorless Distributed Computability Theorems}},
booktitle = {40th International Symposium on Distributed Computing (DISC 2026)},
pages = {61:1--61:7},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-454-3},
ISSN = {1868-8969},
year = {2026},
volume = {397},
editor = {Moses Jr., William K. and Censor-Hillel, Keren},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2026.61},
URN = {urn:nbn:de:0030-drops-281679},
doi = {10.4230/LIPIcs.DISC.2026.61},
annote = {Keywords: simplicial complex, partial order, spectral spaces, Stone duality, categorical semantics}
}