Papers

Online Papers

Strong Completeness of a First-Order Temporal Logic for Real Time.
The Review of Symbolic Logic, open access at doi: 10.1017/S1755020324000121, published online 22 May 2024.
[arXiv abstract and preprint]
Canonicity in Power and Modal Logics of Finite Achronal Width.
With Ian Hodkinson. The Review of Symbolic Logic, open access at doi: 10.1017/S1755020323000060, published online 22 March 2023.
[arXiv abstract and preprint]
Cover Systems for the Modalities of Linear Logic.
In Hiroakira Ono on Residuated Lattices and Substructural Logics, edited by N. Galatos and K. Terui, Springer, 2022, pp. 299-318. doi: 10.1007/978-3-030-76920-8_8
[arXiv preprint]
Completeness of Pledger's Modal Logics of One-Sorted Projective and Elliptic Planes.
Australasian Journal of Logic, Volume 18, Number 4, 2021, pp. 106 - 131. Open access at doi: 10.26686/ajl.v18i4.6829.
Modal Logics of Some Hereditarily Irresolvable Spaces.
In Alasdair Urquhart on Nonclassical and Algebraic Logic and Complexity of Proofs, edited by Ivo Duntsch and Edwin Mares, Springer, 2021, pp. 303-322. doi.org/10.1007/978-3-030-71430-7_11
[arXiv abstract and preprint]
Modal Logics that Bound the Circumference of Transitive Frames.
In Hajnal Andreka and Istvan Nemeti on Unity of Science: From Computing to Relativity Theory Through Algebraic Logic, edited by Judit Madarasz and Gergely Szekely, Springer,2021, pp. 233-265. doi: 10.1007/978-3-030-64187-0_10
[arXiv abstract and preprint]
Strong completeness of modal logics over 0-dimensional metric spaces.
With Ian Hodkinson. The Review of Symbolic Logic, Volume 13, Issue 3, September 2020, pp. 611-632. doi: 10.1017/S1755020319000534, published online 24 October 2019.
[arXiv abstract and preprint]
Morphisms and Duality for Lattices with Operators.
Journal of Applied Logics - IfCoLog Journal of Logics and their Applications, Volume 7, no. 6, 2020, pp. 1019-1072, open access.
Reprinted in Selected Topics in Contemporary Logics , edited by Melvin Fitting, College Publications, London, 2021, pp. 247-299.
[arXiv abstract and preprint]
Definable Operators on Stable Set Lattices. Studia Logica, Volume 108, Issue 6, December 2020, pp. 1263-1280. doi: 10.1007/s11225-020-09896-0, published online 5 February 2020.
[arXiv abstract and preprint]
Canonical Extensions and Ultraproducts of Polarities.
In memoriam Bjarni Jónsson.
Algebra Universalis, Volume 79, Issue 4, Article 80, 2018. doi: 10.1007/s00012-018-0562-4, available online 8 October 2018.
[arXiv abstract and preprint]
Representing and Completing Lattices by Propositions of Cover Systems.
In Philosophical Logic: Current Trends in Asia - Proceedings of AWPL-TPLC 2016, edited by Syraya Chin-Mu Yang, Kok Yong Lee and Hiroakira Ono, Springer, 2017, pp. 17-36. doi: 10.1007/978-981-10-6355-8_1
[preprint pdf]
The Finite Model Property for Logics with the Tangle Modality.
With Ian Hodkinson. Studia Logica, Volume 106, Issue 1, February 2018, pp. 131-166, doi: 10.1007/s11225-017-9732-1, open access, available online 1 June 2017.

Includes material from the arXiv preprint Spatial Logic of Modal Mu-Calculus and Tangled Closure Operators.
Tangled Closure Algebras.
With Ian Hodkinson. Categories and General Algebraic Structures with Applications, Volume 7, 2017, pp. 9-31, open access, available online 26 January 2017.
[arXiv preprint]
Spatial Logic of Tangled Closure Operators and Modal Mu-Calculus.
With Ian Hodkinson. Annals of Pure and Applied Logic, Volume 168, Issue 5, May 2017, pp. 1032-1090. doi: 10.1016/j.apal.2016.11.006, open access, available online 21 November 2016.

Includes material from the arXiv preprint Spatial Logic of Modal Mu-Calculus and Tangled Closure Operators.
The Tangled Derivative Logic of the Real Line and Zero-Dimensional Spaces.
With Ian Hodkinson. In Advances in Modal Logic, vol. 11, open access, edited by Lev Beklemishev, Stéphane Demri and András Máté, College Publications, 2016, 342-361.
Mereocompactness and Duality for Mereotopological Spaces.
With Matt Grice. In J. Michael Dunn on Information Based Logics, edited by Katalin Bimbo, Springer, 2016, pp. 313-330. doi: 10.1007/978-3-319-29300-4_15
[abstract] [preprint pdf]
Ultraproducts of Admissible Models for Quantified Modal Logic.
In Structural Analysis of Non-Classical Logics - Proceedings of the Second Taiwan Philosophical Logic Colloquium TPLC-2014, edited by D. M. Deng, Hanti Lin, and Syraya C. M. Yang. Springer, pp. 17-36. doi:10.1007/978-3-662-48357-2_2
[abstract] [preprint pdf]
Spatial Logic of Modal Mu-Calculus and Tangled Closure Operators.
With Ian Hodkinson.
[arXiv preprint]
Fine's Theorem on First-Order Complete Modal Logics.
In Metaphysics, Meaning and Modality. Themes from Kit Fine, edited by Mircea Dumitru, Oxford University Press, 2020, pp. 316-334.
[arXiv preprint]
The Countable Henkin Principle.
In The Life and Work of Leon Henkin, Essays on His Contributions, edited by Maria Manzano, Ildiko Sain and Enrique Alonso, Springer, 2014, pp. 179-201. doi:10.1007/978-3-319-09719-0_13
[abstract] [preprint pdf]
Equivalent Beliefs in Dynamic Doxastic Logic.
In Krister Segerberg on Logic of Actions, edited by Robert Trypuz, Springer, 2014, pp. 179-207. doi:10.1007/978-94-007-7046-1_9
[abstract] [preprint pdf]
The Power of a Propositional Constant.
With Tomasz Kowalski. Journal of Philosophical Logic, 16 December 2012. doi:10.1007/s10992-012-9256-0
[abstract] [preprint pdf]
Well Structured Program Equivalence is Highly Undecidable.
With Marcel Jackson. ACM Transactions on Computational Logic, Volume 13 Issue 3, Article 26, August 2012. doi:10.1145/2287718.2287726
[abstract] [preprint pdf]
Topological Proofs of Some Rasiowa-Sikorski Lemmas.
Studia Logica, vol. 100, nos. 1-2, April 2012, pp. 175-191. Special issue dedicated to the memory of Leo Esakia, doi:10.1007/s11225-012-9374-2
[abstract] [preprint pdf]
Grishin Algebras and Cover Systems for Classical Bilinear Logic
Studia Logica, vol. 99, 2011, pp. 203-227, doi:10.1007/s11225-011-9360-0
[abstract] [preprint pdf]
Cover Semantics for Quantified Lax Logic
Journal of Logic and Computation, 2010. doi:10.1093/logcom/exq029
[abstract] [preprint pdf]
Deduction Systems for Coalgebras Over Measurable Spaces
Journal of Logic and Computation, Vol. 20, Issue 5, October 2010, 1069-1100. Published online December 12, 2008, doi: 10.1093/logcom/exn092
[abstract] [preprint pdf]
Functional Monadic Bounded Algebras
Studia Logica, vol. 96, no. 1, 2010, pp. 41-48. doi:10.1007/s11225-010-9271-5
[abstract] [preprint pdf]
Monadic Bounded Algebras
With Galym Akishev. Studia Logica, vol. 96, no. 1, 2010, pp. 1-40. doi:10.1007/s11225-010-9269-z
[abstract] [preprint pdf]
An Admissible Semantics for Propositionally Quantified Relevant Logics
With Michael Kane. Journal of Philosophical Logic, , vol. 39, no. 1, 2010, pp. 73-100. Published on-line 5 August 2009, doi:10.1007/s10992-009-9109-7.
[abstract] [preprint pdf]
Conservativity of Heyting Implication Over Relevant Quantification
Review of Symbolic Logic, vol. 2, no. 2, 2009, pp. 310- 341. © 2009 Association for Symbolic Logic. doi:10.1017/S1755020309090194
[abstract] [published version pdf]
Commutativity of Quantifiers in Varying-Domain Kripke Models
With Ian Hodkinson. In Towards Mathematical Philosophy , David Makinson, Jacek Malinowski and Heinrich Wansing (eds.), Volume 28 of Trends in Logic, Springer, 2009, 9 - 30.
[abstract] [pdf]
The McKinsey--Lemmon Logic Is Barely Canonical
With Ian Hodkinson. Australasian Journal of Logic, vol. 5, 2007, pp. 1-19.
[abstract] [pdf] (the published version is freely downloadable from the journal website )
A General Semantics for Quantified Modal Logic
With Edwin Mares. Advances in Modal Logic, Volume 6, Guido Governatori, Ian Hodkinson and Yde Venema, editors. College Publications, London, 2006, 227-246.
[abstract] [pdf]
A Kripke-Joyal Semantics for Noncommutative Logic in Quantales
Advances in Modal Logic, Volume 6, Guido Governatori, Ian Hodkinson and Yde Venema, editors. College Publications, London, 2006, 209-225.
[abstract] [pdf]
A Modal Proof Theory for Final Polynomial Coalgebras
With David Friggens. Theoretical Computer Science, vol. 360, Issues 1-3, 2006, pp 1-22.
[abstract] [pdf]
Constant Modal Logics and Canonicity
In Modality Matters. Twenty-Five Essays in Honour of Krister Segerberg, edited by Henrik Lagerlund, Sten Lindström and Rysiek Sliwinski, Uppsala Philosophical Studies 53, Uppsala University, 2006, 149-157.
[abstract] [pdf]
Maps and Monads for Modal Frames
Studia Logica, vol. 83, 2006, 307-329.
[abstract] [pdf]
An Alternative Semantics for Quantified Relevant Logic
With Edwin Mares. The Journal of Symbolic Logic, vol. 71, no. 1, March 2006, 163-187.
[abstract] [pdf]
Final Coalgebras and the Hennessy-Milner Property
Annals of Pure and Applied Logic, vol. 183, 77-93, 2006.
[abstract] [pdf]
Axiomatic Classes of Intuitionistic Models
Journal of Universal Computer Science, vol. 11, Issue 12, pp 1945-1962, 2005.
[abstract] [pdf]
Covarieties of Coalgebras: Comonads and Coequations
With Ranald Clouston. In Theoretical Aspects of Computing - ICTAC 2005, Dang Van Hung and Martin Wirsing (eds.), Lecture Notes in Computer Science vol. 3722 , pp 288-302. © Springer-Verlag, 2005.
[abstract ] [pdf]
A Comonadic Account of Behavioural Covarieties of Coalgebras
Mathematical Structures in Computer Science, © Cambridge University Press, vol. 15, 2005, 243-269.
[abstract] [pdf]
On Canonical Modal Logics That Are Not Elementarily Determined
With Ian Hodkinson and Yde Venema. Logique et Analyse, vol. 181, 2003, 77-101.
In a Festschrift for Max Cresswell on the occasion of his 65th birthday.
[abstract] [pdf]
Erdos Graphs Resolve Fine's Canonicity Problem
With Ian Hodkinson and Yde Venema. The Bulletin of Symbolic Logic, vol. 10, no. 2, June 2004, 186-208.
[abstract] [pdf]
A Compactification of Polynomial Coalgebras
Topology Proceedings, vol. 27, no. 2, 2003, 439-459.
[abstract] [pdf]
Mathematical Modal Logic: a View of its Evolution
Revised version, in Logic and the Modalities in the Twentieth Century, Volume 7 of the Handbook of the History of Logic, edited by Dov M. Gabbay and John Woods, Elsevier, 2006, pp 1-98.
Contains a new Section 7.7 on Modal Logic for Coalgebras.
[abstract] [Table of Contents] [ pdf ]
Enlargements of Polynomial Coalgebras
In Proceedings of the 7th and 8th Asian Logic Conferences, R. Downey et alia (editors), World Scientific, 2003, pp 152-192.
[abstract] [pdf]
Questions of Canonicity
In Trends in Logic: 50 Years of Studia Logica, Vincent F. Hendricks and Jacek Malinowski (eds), Kluwer Academic Publishers, 2003, pp 93-128.
[abstract] [pdf]
Observational Ultraproducts of Polynomial Coalgebras
Annals of Pure and Applied Logic, vol. 123, 2003, 235-290.
[abstract] [pdf]
Equational Logic of Polynomial Coalgebras
Advances in Modal Logic, Volume 4. Philippe Balbiani, Nobu-Yuki Suzuki, Frank Wolter, and Michael Zakharyaschev (editors), King's College Publications, King's College London, 2003, 149-184.
[abstract] [pdf]
A Calculus of Terms for Coalgebras of Polynomial Functors (24 pp)
In CMCS 2001: 4th International Workshop on Coalgebraic Methods in Computer Science, Electronic Notes in Theoretical Computer Science, Volume 44, Issue 1, 2001.
[abstract] [pdf]
Persistence and Atomic Generation for Varieties of Boolean Algebras with Operators
Studia Logica, vol. 68, No. 2, July 2001, 155-171.
[abstract] [pdf]
Duality for Some Categories of Coalgebras
Algebra Universalis, vol. 46, 2001, 389-416.
[abstract] [pdf]
What is the Coalgebraic Analogue of Birkhoff's Variety Theorem?
Theoretical Computer Science, vol. 266, 2001, 853-886.
[abstract] [pdf]
Quasi-Modal Equivalence of Canonical Structures
The Journal of Symbolic Logic, vol. 66, No. 2, June 2001, 497-508.
[abstract] [pdf]
Algebraic Polymodal Logic: A Survey
Logic Journal of the IGPL, Volume 8, Issue 4, July 2000, pages 393--450,
Special Issue on Algebraic Logic edited by Istvan Nemeti and Ildiko Sain.
[abstract] [pdf ]
Reflections on a Proof of Elementarity
in JFAK. Essays Dedicated to Johan van Benthem on the Occasion of his 50th Birthday,
ed. by J. Gerbrandy, M. Marx, M. de Rijke and Y. Venema, Amsterdam University Press, 1999.
[abstract] [pdf]