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On modal logics between K × K × K and S5 × S5 × S5

Published online by Cambridge University Press:  12 March 2014

R. Hirsch
Affiliation:
Department of Computer Science, University College, Gower Street, London WC1E 6BT, UK, E-mail: r.hirsch@cs.ucl.ac.uk
I. Hodkinson
Affiliation:
Department of Computing, Imperial College, 180 Queen's Gate, London SW7 2BZ, UK, E-mail: imh@doc.ic.ac.uk
A. Kurucz
Affiliation:
Department of Computer Science, King's College, Strand, London WC2R 2LS, UK, E-mail: kuag@dcs.kcl.ac.uk

Abstract

We prove that every n-modal logic between Kn and S5n is undecidable, whenever n ≥ 3. We also show that each of these logics is non-finitely axiomatizable, lacks the product finite model property, and there is no algorithm deciding whether a finite frame validates the logic. These results answer several questions of Gabbay and Shehtman. The proofs combine the modal logic technique of Yankov–Fine frame formulas with algebraic logic results of Halmos, Johnson and Monk, and give a reduction of the (undecidable) representation problem of finite relation algebras.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2002

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References

REFERENCES

[1]Chagrov, A. and Zakharyaschev, M., Modal logic, Oxford Logic Guides, no. 35, Oxford University Press, 1997.CrossRefGoogle Scholar
[2]Gabbay, D. M., Fibring logics, Clarendon Press, Oxford, 1999.Google Scholar
[3]Gabbay, D. M., Kurucz, A., Wolter, F., and Zakharyaschev, M., Many-dimensional modal logics: theory and applications, Studies in Logic, Elsevier, to appear.Google Scholar
[4]Gabbay, D. M. and Shehtman, V. B., Undecidability of modal and intermediate first-order logics with two individual variables, this Journal, vol. 58 (1993), pp. 800823.Google Scholar
[5]Gabbay, D. M. and Shehtman, V. B., Products of modal logics, part I, Logic Journal of the Interest Group in Pure and Applied Logic, vol. 6 (1998), pp. 73146.Google Scholar
[6]Halmos, P., Algebraic logic, IV, Transactions ofthe American Mathematical Society, vol. 86 (1957), pp. 127.Google Scholar
[7]Henkin, L., Monk, J. D., and Tarski, A., Cylindric algebras, part II, North Holland, 1985.Google Scholar
[8]Hirsch, R. and Hodkinson, I., Representability is not decidable for finite relation algebras, Transactions of the American Mathematical Society, vol. 353 (2001), pp. 14031425.CrossRefGoogle Scholar
[9]Johnson, J. S., Nonfinitizability of classes of representable polyadic algebras, this Journal, vol. 34 (1969), pp. 344352.Google Scholar
[10]Kurucz, A., On axiomatising products of Kripke frames, this Journal, vol. 65 (2000), pp. 923945.Google Scholar
[11]Kurucz, A., S5 × S5 × S5 lacks the finite model property, Advances in modal logic (Wolter, F., Wansing, H., de Rijke, M., and Zakharyaschev, M., editors), vol. 3, CSLI Publications, to appear, available at http://www.doc.ic.ac.uk/~kuag/fmp.ps.Google Scholar
[12]Maddux, R., The equational theory of CA3 is undecidable, this Journal, vol. 45 (1980), pp. 311316.Google Scholar
[13]Maddux, R., Introductory course on relation algebras, finite-dimensional cylindric algebras, and their interconnections, Algebraic logic (Andréka, H., Monk, J. D., and Németi, I., editors), Colloquia Mathematica Societatis János Bolyai, vol. 54, North-Holland, 1991, pp. 361392.Google Scholar
[14]Marx, M., Complexity of products of modal logics, Journal of Logic and Computation, vol. 9 (1999), pp. 197214.CrossRefGoogle Scholar
[15]Monk, J. D., Studies in cylindric algebra, doctoral dissertation, University of California, Berkeley, 1961.Google Scholar
[16]Segerberg, K., Two-dimensional modal logic, Journal of Philosophical Logic, vol. 2 (1973), pp. 7796.CrossRefGoogle Scholar
[17]Shehtman, V., Two-dimensional modal logics, Mutematicheskie Zametki, vol. 5 (1978), pp. 759772.Google Scholar
[18]Spaan, E., Complexity of modal logics, Ph.D. thesis, University of Amsterdam, 1993.Google Scholar
[19]Wolter, F. and Zakharyaschev, M., Modal description logics: modalizing roles, Fundamenta Informaticae, vol. 39 (1999), pp. 411438.CrossRefGoogle Scholar
[20]Wolter, F. and Zakharyaschev, M., Spatio-temporal representation and reasoning based on RCC-8, Proceedings of the 7th conference on principles of knowledge representation and reasoning (KR-2000) (Montreal, Canada), Morgan Kaufman, 2000, pp. 314.Google Scholar