Combinatorics and quantifiers

Jaroslav Nešetřil

Commentationes Mathematicae Universitatis Carolinae (1996)

  • Volume: 37, Issue: 3, page 433-443
  • ISSN: 0010-2628

Abstract

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Let I m be the set of subsets of I of cardinality m . Let f be a coloring of I m and g a coloring of I m . We write f g if every f -homogeneous H I is also g -homogeneous. The least m such that f g for some f : I m k is called the k -width of g and denoted by w k ( g ) . In the first part of the paper we prove the existence of colorings with high k -width. In particular, we show that for each k > 0 and m > 0 there is a coloring g with w k ( g ) = m . In the second part of the paper we give applications of wide colorings in the theory of generalized quantifiers. In particular, we show that for every monadic similarity type t = ( 1 , ... , 1 ) there is a generalized quantifier of type t which is not definable in terms of a finite number of generalized quantifiers of a smaller type.

How to cite

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Nešetřil, Jaroslav. "Combinatorics and quantifiers." Commentationes Mathematicae Universitatis Carolinae 37.3 (1996): 433-443. <http://eudml.org/doc/247917>.

@article{Nešetřil1996,
abstract = {Let $\binom\{I\}\{m\}$ be the set of subsets of $I$ of cardinality $m$. Let $f$ be a coloring of $\binom\{I\}\{m\}$ and $g$ a coloring of $\binom\{I\}\{m\}$. We write $f\rightarrow g$ if every $f$-homogeneous $H\subseteq I$ is also $g$-homogeneous. The least $m$ such that $f\rightarrow g$ for some $f:\binom\{I\}\{m\}\rightarrow k$ is called the $k$-width of $g$ and denoted by $w_k(g)$. In the first part of the paper we prove the existence of colorings with high $k$-width. In particular, we show that for each $k>0$ and $m>0$ there is a coloring $g$ with $w_k(g)=m$. In the second part of the paper we give applications of wide colorings in the theory of generalized quantifiers. In particular, we show that for every monadic similarity type $t=(1,\ldots ,1)$ there is a generalized quantifier of type $t$ which is not definable in terms of a finite number of generalized quantifiers of a smaller type.},
author = {Nešetřil, Jaroslav},
journal = {Commentationes Mathematicae Universitatis Carolinae},
keywords = {generalized quantifier; Ramsey theory; generalized quantifier; Ramsey theory},
language = {eng},
number = {3},
pages = {433-443},
publisher = {Charles University in Prague, Faculty of Mathematics and Physics},
title = {Combinatorics and quantifiers},
url = {http://eudml.org/doc/247917},
volume = {37},
year = {1996},
}

TY - JOUR
AU - Nešetřil, Jaroslav
TI - Combinatorics and quantifiers
JO - Commentationes Mathematicae Universitatis Carolinae
PY - 1996
PB - Charles University in Prague, Faculty of Mathematics and Physics
VL - 37
IS - 3
SP - 433
EP - 443
AB - Let $\binom{I}{m}$ be the set of subsets of $I$ of cardinality $m$. Let $f$ be a coloring of $\binom{I}{m}$ and $g$ a coloring of $\binom{I}{m}$. We write $f\rightarrow g$ if every $f$-homogeneous $H\subseteq I$ is also $g$-homogeneous. The least $m$ such that $f\rightarrow g$ for some $f:\binom{I}{m}\rightarrow k$ is called the $k$-width of $g$ and denoted by $w_k(g)$. In the first part of the paper we prove the existence of colorings with high $k$-width. In particular, we show that for each $k>0$ and $m>0$ there is a coloring $g$ with $w_k(g)=m$. In the second part of the paper we give applications of wide colorings in the theory of generalized quantifiers. In particular, we show that for every monadic similarity type $t=(1,\ldots ,1)$ there is a generalized quantifier of type $t$ which is not definable in terms of a finite number of generalized quantifiers of a smaller type.
LA - eng
KW - generalized quantifier; Ramsey theory; generalized quantifier; Ramsey theory
UR - http://eudml.org/doc/247917
ER -

References

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  8. Nešetřil J., Ramsey Theory, In: , (ed. R.L. Graham, M. Grötschel, L. Lovász), North-Holland, 1995. MR1373681
  9. Nešetřil J., Rödl V., A simple proof of Galvin-Ramsey property of all finite graphs and a dimension of a graph, Discrete Mathematics 23 (1978), 49-55. (1978) MR0523311
  10. Nešetřil J., Rödl V., A structural generalization of the Ramsey theorem, Bull. Amer. Math. Soc. 83 (1977), 127-128. (1977) MR0422035
  11. Shelah S., A finite partition theorem with double exponential bounds, to appear in (ed. R.L. Graham and J. Nešetřil), Springer Verlag, 1996. MR1425218
  12. Väänänen J., Unary quantifiers on finite structures, to appear. 
  13. Westerståhl D., Personal communication, . 

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