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Finite presentation of homogeneous graphs, posets and Ramsey classes

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Abstract

It is commonly believed that one can prove Ramsey properties only for simple and “well behaved” structures. This is supported by the link of Ramsey classes of structures with homogeneous structures. We outline this correspondence in the context of the Classification Programme for Ramsey classes. As particular instances of this approach one can characterize all Ramsey classes of graphs, tournaments and partial ordered sets and also fully characterize all monotone Ramsey classes of relational systems (of any type). On the other side of this spectrum many homogeneous structures allow a concise description (called here a finite presentation) by means of all finite models of a suitable theory. Extending classical work of Rado (for the random graph) we find a finite presentation for each of the above classes where the classification problem is solved: (undirected) graphs, tournaments and partially ordered sets. The main result of the paper is a construction of classesP andP f of finite structures which are isomorphic to the generic (i.e. homogeneous and universal) partially ordered set. Somehow surprisingly, the structureP extends Conway’s surreal numbers and their linear ordering.

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References

  1. L. Babai,Automorphism groups of graphs and edge contraction, Discrete Mathematics8 (1974), 13–22.

    Article  MATH  MathSciNet  Google Scholar 

  2. L. Babai and A. Pultr,Endomorphism monoids and topological subgraphs of graphs, Journal of Combinatorial Theory B28 (1980), 278–283.

    Article  MATH  MathSciNet  Google Scholar 

  3. P. J. Cameron,The random graph, inThe Mathematics of Paul Erdös (R. L. Graham and J. Nešetřil, eds.), Springer-Verlag, Berlin, 1998, pp. 333–351.

    Google Scholar 

  4. G. L. Cherlin,The classification of countable homogeneous directed graphs and countable homogeneous n-tournaments, Memoirs of the American Mathematical Society 621, American Mathematical Society, Providence, RI, 1998.

    Google Scholar 

  5. G. L. Cherlin,Combinatorial problems connected with finite homogeneity, Contemporary Mathematics131 (1992), 3–30.

    MathSciNet  Google Scholar 

  6. J. H. Conway,On Numbers and Games, London Mathematical Society Monographs, Academic Press, New York, 1976.

    Google Scholar 

  7. P. Ehrlich,Number systems with simplicity hiearchies. A generalization of Conway’s theory of surreal numbers, Journal of Symbolic Logic66 (2001), 1231–1258.

    Article  MATH  MathSciNet  Google Scholar 

  8. R. Fraïssé,Théorie des relations, North-Holland, Amsterdam, 1986.

    Google Scholar 

  9. H. Furstenberg,Recurrence in Ergodic Theory and Combinatorial Number Theory, Princeton University Press, Princeton, 1981.

    MATH  Google Scholar 

  10. G. Gambosi, J. Nešetřil and M. Talamo,On locally presented posets, Theoretical Computer Science70 (1990), 251–260.

    Article  MATH  MathSciNet  Google Scholar 

  11. R. L. Graham, K. Leeb and B. L. Rothschild,Ramsey’s theorem for a class of categories, Advances in Mathematics8 (1972), 417–433.

    Article  MATH  MathSciNet  Google Scholar 

  12. R. L. Graham, B. L. Rothschild and J. Spencer,Ramsey Theory, Wiley, New York, 1980 (2nd edition 1990).

    MATH  Google Scholar 

  13. Z. Hedrlín,On universal partly oriented sets and classes, Journal of Algebra11 (1969), 503–509.

    Article  MATH  MathSciNet  Google Scholar 

  14. W. Hodges,Model Theory, Cambridge University Press, 1993.

  15. J. Hubička and J. Nešetřil,On universal posets represented by means of trees and other simple graphs, ITI Series 2003-620 (to appear in European J. Comb.).

  16. A. S. Kechris, V. G. Pestov and S. Todorcevic,Fraïssé limits, Ramsey theory, and topological dynamics of automorphism groups, Geometric and Functional Analysis, to appear.

  17. D. E. Knuth,Surreal Numbers, Addison-Wesley, Redwood City, CA, 1974.

    MATH  Google Scholar 

  18. A. H. Lachlan and R. E. Woodrow,Countable ultrahomogeneous undirected graphs, Transactions of the American Mathematical Society262 (1980), 51–94.

    Article  MATH  MathSciNet  Google Scholar 

  19. A. H. Lachlan,Countable homogeneous tournaments, Transactions of the American Mathematical Society284 (1984), 431–461.

    Article  MATH  MathSciNet  Google Scholar 

  20. A. H. Lachlan,Homogeneous Structures, inProceedings of the ICM 1986, American Mathematical Society, Providence, RI, 1987, pp. 314–321.

    Google Scholar 

  21. K. Leeb,Vorlesungen über Pascaltheorie, Universität Erlangen, 1973.

  22. M. Naor,Succinct representation of general unlabeled graphs, Discrete Applied Mathematics28 (1990), 303–307.

    Article  MATH  MathSciNet  Google Scholar 

  23. J. Nešetřil,For graphs there are only four types of hereditary Ramsey Classes, Journal of Combinatorial Theory B46 (1989), 127–132.

    Article  MATH  Google Scholar 

  24. J. Nešetřil,Ramsey classes and homogeneous structures, Combinatorics, Probability and Computing14 (2005), 171–189.

    Article  MathSciNet  MATH  Google Scholar 

  25. J. Nešetřil,Ramsey theory, inHandbook of Combinatorics (R. L. Graham, M. Grötschel and L. Lovász, eds.), Elsevier, Amsterdam, 1995, pp. 1331–1403.

    Google Scholar 

  26. J. Nešetřil,On Universality of Set Systems, KAM-DIMATIA Series 491, Charles University, 2000.

  27. J. Nešetřil and P. Pudlák,A note on Boolean dimension of posets, inIrregularities of Partitions (W. Deuber and V. T. Sós, eds.), Algorithms and Combinatorics 8, Springer, Berlin, 1989, pp. 137–140.

    Google Scholar 

  28. J. Nešetřil and V. Rödl,Partitions of finite relational and set systems, Journal of Combinatorial Theory, Series A22 (1978), 289–312.

    Google Scholar 

  29. J. Nešetřil and V Rödl,Combinatorial partitions of finite posets and lattices — Ramsey lattices, Algebra Universalis19 (1984), 106–119.

    Article  MathSciNet  Google Scholar 

  30. J. Nešetřil and V Rödl,Mathematics of Ramsey Theory, Springer, Berlin, 1990.

    MATH  Google Scholar 

  31. J. Nešetřil and V Rödl,Partite construction and Ramsey space systems, in [30], pp. 98–112.

    Google Scholar 

  32. J. Nešetřil and V Rödl,Type theory of partition properties of graphs, inRecent Advances in Graph Theory (M. Fiedler, ed.), Academia, Prague, 1975, pp. 405–412.

    Google Scholar 

  33. J. Nešetřil and V Rödl,Strong Ramsey theorems for Steiner systems, Transactions of the American Mathematical Society303 (1987), 183–192.

    Article  MathSciNet  MATH  Google Scholar 

  34. J. Nešetřil and X. Zhu,Path homomorphisms, Mathematical Proceedings of the Cambridge Philosophical Society120 (1996), 207–220.

    Article  MathSciNet  MATH  Google Scholar 

  35. A. Pultr and V. Trnková,Combinatorial, Algebraic and Topological Representations of Groups, Semigroups and Categories, North-Holland, Amsterdam, 1980.

    MATH  Google Scholar 

  36. J. Schmerl,Countable homogeneous partialy ordered sets, Algebra Universalis9 (1979), 317–321.

    Article  MATH  MathSciNet  Google Scholar 

  37. G. Turán,Succinct representations of graphs, Discrete Applied Mathematics8 (1984), 289–294.

    Article  MATH  MathSciNet  Google Scholar 

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Dedicated to Professor Hillel Furstenberg

Supported by Grants LN00A56 and 1M0021620808 of the Czech Ministry of Education and ICREA, Barcelona, Spain.

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Hubička, J., Nešetřil, J. Finite presentation of homogeneous graphs, posets and Ramsey classes. Isr. J. Math. 149, 21–44 (2005). https://doi.org/10.1007/BF02772535

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