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Undefinability of κ-well-orderings in Lκ

Published online by Cambridge University Press:  12 March 2014

Juha Oikkonen*
Affiliation:
Helsingin Yliopisto, Matematiikan Laiton, PI 4 (Yliopistonkatu 5), 00014 Helsingin Yliopisto, Finland, E-mail: oikkonen@cc.helsinki.fi

Abstract

We prove that the class of trees with no branches of cardinality ≤ κ is not RPC definable in Lκ when κ is regular. Earlier such a result was known for under the assumption κ<κ = κ. Our main result is actually proved in a stronger form which covers also Lκ (and makes sense there) for every strong limit cardinal λ < κ of cofinality κ.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1997

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References

REFERENCES

[1]Chang, C. C., Two interpolation theorems, Instituto Nazionale di Alta Matematica, Symposia Matematica, vol. V (1970), pp. 519.Google Scholar
[2]Cunningham, E., Applications of consistency properties and back-and-forth techniques in infinite-quantifier languages, in Karp-memoirs.Google Scholar
[3]Dickmann, M., Large infinitary languages—model theory, North-Holland, Amsterdam, 1975.Google Scholar
[4]Green, J., Consistency properties for finite quantifier languages, Infinitary logic: In memoriam Carol Karp (Kueker, D. W., editor), Lecture Notes in Mathematics, vol. 492, 1975, pp. 74123.Google Scholar
[5]Hintikka, J. and Rantala, V., A new approach to infinitary languages, Annals of Mathematical Logic, vol. 10 (1976), pp. 95115.CrossRefGoogle Scholar
[6]Hyttinen, T., Model theory for infinite quantifier languages, Fundamenta Mathematicae, vol. 134 (1990), pp. 125142.CrossRefGoogle Scholar
[7]Karp, C., Infinite quantifier languages and ω-chains of models, Proceedings of the Tarski symposium, American Mathematical Society, 1974, pp. 225232.CrossRefGoogle Scholar
[8]Karttunen, M., Model theory for infinitely deep languages, Annales Academiae Scientiarum Fennicae. Series A I. Mathematica Dissertationes, vol. 50 (1984).Google Scholar
[9]Keisler, H. J., Model theory for infinitary logic, North-Holland, 1971.Google Scholar
[10]López-Escobar, E. G. K., On defining well-orderings, Fundamenta Mathematicae, vol. LIX (1966), pp. 1321.CrossRefGoogle Scholar
[11]López-Escobar, E. G. K., An addition to On defining well-orderings, Fundamenta Mathematicae, vol. LIX (1966), pp. 299300.CrossRefGoogle Scholar
[12]Makkai, M., Generalizing Vaught sentences from ω to strong cofinality ω, Fundamenta Mathematicae, vol. LXXXII (1974), pp. 105119.CrossRefGoogle Scholar
[13]Makkai, M., Admissible sets and infinitary logic, Handbook of mathematical logic (Barwise, J., editor), North-Holland, 1977, pp. 739782.Google Scholar
[14]Mekler, A. and Väänänen, J., Trees and -subsets of , this Journal, vol. 58 (1993), pp. 10521070.Google Scholar
[15]Oikkonen, J., Separation for infinitary logic of uncountable cofinality, to appear.Google Scholar
[16]Oikkonen, J., over , Reports from the Department of Philosophy 3, University of Helsinki, 1983.Google Scholar
[17]Oikkonen, J., How to obtain interpolation for , Logic colloquium '86 (Drake, F. R. and Truss, J. K., editors), North-Holland, 1988, pp. 175208.Google Scholar
[18]Oikkonen, J., Ehrenfeucht-Fraïssé equivalence of linear ordering, this Journal, vol. 55 (1990), no. 1, pp. 6573.Google Scholar
[19]Oikkonen, J., Chain models and infinitely deep logics, Reports of the Department of Mathematics, University of Helsinki, 1992, preprint 13.Google Scholar
[20]Svenonius, L., On the denumerable models of theories with extra predicates, The theory of models (Addison, , Henkin, , and Tarski, , editors), North-Holland, 1965, pp. 376389.Google Scholar
[21]Tuuri, H., Relative separation theorems for , Notre Dame Journal of Formal Logic, vol. 33 (1992), no. 3, pp. 383401.CrossRefGoogle Scholar
[22]Vaught, R., Descriptive set theory in , Cambridge summer school in mathematical logic, Lecture Notes in Mathematics, vol. 337, Springer-Verlag, 1973, pp. 574598.CrossRefGoogle Scholar