Compositions of simple maps

Jerzy Krzempek

Fundamenta Mathematicae (1999)

  • Volume: 162, Issue: 2, page 149-162
  • ISSN: 0016-2736

Abstract

top
A map (= continuous function) is of order ≤ k if each of its point-inverses has at most k elements. Following [4], maps of order ≤ 2 are called simple.  Which maps are compositions of simple closed [open, clopen] maps? How many simple maps are really needed to represent a given map? It is proved herein that every closed map of order ≤ k defined on an n-dimensional metric space is a composition of (n+1)k-1 simple closed maps (with metric domains). This theorem fails to be true for non-metrizable spaces. An appropriate map on a Cantor cube of uncountable weight is described.

How to cite

top

Krzempek, Jerzy. "Compositions of simple maps." Fundamenta Mathematicae 162.2 (1999): 149-162. <http://eudml.org/doc/212416>.

@article{Krzempek1999,
abstract = { A map (= continuous function) is of order ≤ k if each of its point-inverses has at most k elements. Following [4], maps of order ≤ 2 are called simple.  Which maps are compositions of simple closed [open, clopen] maps? How many simple maps are really needed to represent a given map? It is proved herein that every closed map of order ≤ k defined on an n-dimensional metric space is a composition of (n+1)k-1 simple closed maps (with metric domains). This theorem fails to be true for non-metrizable spaces. An appropriate map on a Cantor cube of uncountable weight is described. },
author = {Krzempek, Jerzy},
journal = {Fundamenta Mathematicae},
keywords = {composition; simple map; closed map; map of order ≤ k; finite-dimensional; zero-dimensional; Cantor cube; metric space; finite dimension},
language = {eng},
number = {2},
pages = {149-162},
title = {Compositions of simple maps},
url = {http://eudml.org/doc/212416},
volume = {162},
year = {1999},
}

TY - JOUR
AU - Krzempek, Jerzy
TI - Compositions of simple maps
JO - Fundamenta Mathematicae
PY - 1999
VL - 162
IS - 2
SP - 149
EP - 162
AB - A map (= continuous function) is of order ≤ k if each of its point-inverses has at most k elements. Following [4], maps of order ≤ 2 are called simple.  Which maps are compositions of simple closed [open, clopen] maps? How many simple maps are really needed to represent a given map? It is proved herein that every closed map of order ≤ k defined on an n-dimensional metric space is a composition of (n+1)k-1 simple closed maps (with metric domains). This theorem fails to be true for non-metrizable spaces. An appropriate map on a Cantor cube of uncountable weight is described.
LA - eng
KW - composition; simple map; closed map; map of order ≤ k; finite-dimensional; zero-dimensional; Cantor cube; metric space; finite dimension
UR - http://eudml.org/doc/212416
ER -

References

top
  1. [1] J. D. Baildon, Open simple maps and periodic homeomorphisms, Proc. Amer. Math. Soc. 39 (1973), 433-436. Zbl0268.54013
  2. [2] C. Berge, Espaces topologiques. Fonctions multivoques, Dunod, Paris, 1959. Zbl0088.14703
  3. [3] M. Bognár, On Peano mappings, Acta Math. Hungar. 74 (1997), 221-227. Zbl0924.54018
  4. [4] K. Borsuk and R. Molski, On a class of continuous mappings, Fund. Math. 45 (1957), 84-98. Zbl0081.38803
  5. [5] W. Dębski and J. Mioduszewski, Conditions which ensure that a simple map does not raise dimension, Colloq. Math. 63 (1992), 173-185. Zbl0757.54012
  6. [6] J. Dydak, On elementary maps, ibid. 31 (1974), 67-69. Zbl0291.54008
  7. [7] R. Engelking, Theory of Dimensions, Finite and Infinite, Heldermann, Lemgo, 1995. Zbl0872.54002
  8. [8] R. Engelking, General Topology, PWN, Warszawa, 1977. 
  9. [9] R. Frankiewicz and W. Kulpa, On order topology of spaces having uniform linearly ordered bases, Comm. Math. Univ. Carolin. 20 (1979), 37-41. Zbl0411.54034
  10. [10] W. Hurewicz, Über dimensionserhöhende stetige Abbildungen, J. Reine Angew. Math. 169 (1933), 71-78. 
  11. [11] M. Hušek and H. Ch. Reichel, Topological characterizations of linearly uniformizable spaces, Topology Appl. 15 (1983), 173-188. 
  12. [12] J. Krzempek, On decomposition of projections of finite order, Acta Univ. Carolin. Math. Phys. 36 (1995), 3-8. Zbl0826.54012
  13. [13] A. Kucia and W. Kulpa, Spaces having uniformities with linearly ordered bases, Prace Nauk. Uniw. Śląskiego w Katowicach, Prace Mat. 3 (1973), 45-50. Zbl0255.54020
  14. [14] K. Nagami, Mappings of finite order and dimension theory, Japan. J. Math. 30 (1960), 25-54. Zbl0106.16002
  15. [15] J. H. Roberts, A theorem on dimension, Duke Math. J. 8 (1941), 565-574. Zbl0061.40101
  16. [16] K. Sieklucki, On superposition of simple mappings, Fund. Math. 48 (1960), 217-228. Zbl0105.16405
  17. [17] Yu. M. Smirnov, An example of a zero-dimensional space which has infinite covering dimension, Dokl. Akad. Nauk SSSR 123 (1958), 40-42 (in Russian). 

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.