ArticleOriginal scientific text

Title

Bimorphisms in pro-homotopy and proper homotopy

Authors 1, 2

Affiliations

  1. Department of Mathematics, University of Tennessee, Knoxville, TN 37996, U.S.A.
  2. Departamento Geometría y Topología, Facultad de Ciencias Matemáticas, Universidad Complutense, 28040 Madrid, Spain

Abstract

A morphism of a category which is simultaneously an epimorphism and a monomorphism is called a bimorphism. The category is balanced if every bimorphism is an isomorphism. In the paper properties of bimorphisms of several categories are discussed (pro-homotopy, shape, proper homotopy) and the question of those categories being balanced is raised. Our most interesting result is that a bimorphism f:X → Y of w(H0) is an isomorphism if Y is movable. Recall that w(H0) is the full subcategory of pro-H0 consisting of inverse sequences in H0, the homotopy category of pointed connected CW complexes.

Keywords

epimorphism, monomorphism, pro-homotopy, shape, proper homotopy

Bibliography

  1. [B] H. J. Baues, Foundations of proper homotopy theory, Draft manuscript, Max-Planck-Institut für Math., 1992.
  2. [Br] E. M. Brown, Proper homotopy theory in simplicial complexes, in: Topology Conference (Virginia Polytechnic Institute and State University), R. F. Dickmann Jr. and P. Fletcher (eds.), Lecture Notes in Math. 375, Springer, Berlin, 1974, 41-46.
  3. [C-G] C. Casacuberta and S. Ghorbal, On homotopy epimorphisms of connective covers, preprint, 1997.
  4. [D1] J. Dydak, The Whitehead and the Smale theorems in shape theory, Dissertationes Math. 156 (1979).
  5. [D2] J. Dydak, Epimorphism and monomorphism in homotopy, Proc. Amer. Math. Soc. 116 (1992), 1171-1173.
  6. [D-S1] J. Dydak and J. Segal, Shape Theory: An Introduction, Lecture Notes in Math. 688, Springer, Berlin, 1978.
  7. [D-S2] J. Dydak and J. Segal, Strong shape theory, Dissertationes Math. 192 (1981).
  8. [Dy-R] E. Dyer and J. Roitberg, Homotopy-epimorphism, homotopy-monomorphism and homotopy-equivalences, Topology Appl. 46 (1992), 119-124.
  9. [Ed-H] D. A. Edwards and H. M. Hastings, Čech and Steenrod Homotopy Theories with Applications to Geometric Topology, Lecture Notes in Math. 542, Springer, Berlin, 1976.
  10. [En1] R. Engelking, General Topology, Heldermann, Berlin, 1989.
  11. [F-T-W] F. T. Farrell, L. R. Taylor and J. B. Wagoner, The Whitehead theorem in the proper category, Compositio Math. 27 (1973), 1-23.
  12. [G] S. Ghorbal, Epimorphisms and monomorphisms in homotopy theory, PhD Thesis, Université Catholique de Louvain, 1996 (in French).
  13. [H-R] P. Hilton and J. Roitberg, Relative epimorphisms and monomorphisms in homotopy theory, Compositio Math. 61 (1987), 353-367.
  14. [H-W] L. Hong and S. Wenhuai, Homotopy epimorphisms in homotopy pushbacks, Topology Appl. 59 (1994), 159-162.
  15. [M-S] S. Mardešić and J. Segal, Shape Theory, North-Holland, Amsterdam, 1982.
  16. [Mat] M. Mather, Homotopy monomorphisms and homotopy pushouts, Topology Appl. 81 (1997), 159-162.
  17. [Mo-P] M. A. Morón and F. R. Ruiz del Portal, On weak shape equivalences, ibid. 92 (1999), 225-236.
  18. [Mu] G. Mukherjee, Equivariant homotopy epimorphisms, homotopy monomorphisms and homotopy equivalences, Bull. Belg. Math. Soc. 2 (1995), 447-461.
  19. [P] T. Porter, Proper homotopy theory, in: Handbook of Algebraic Topology, Elsevier Science, 1995, 127-167.
  20. [S] E. Spanier, Algebraic Topology, McGraw-Hill, New York, 1966.
  21. [Sp] S. Spież, A majorant for the family of all movable shapes, Bull. Acad. Polon. Sci. Sér. Sci. Math. Astronom. Phys. 21 (1973), 615-620.
Pages:
269-286
Main language of publication
English
Received
1998-09-29
Accepted
1999-01-18
Published
1999
Exact and natural sciences