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Numerical Invariants in Homotopical Algebra, I

Published online by Cambridge University Press:  20 November 2018

K. Varadarajan*
Affiliation:
University of Calgary, Calgary, Alberta
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Classically CW-complexes were found to be the best suited objects for studying problems in homotopy theory. Certain numerical invariants associated to a CW-complex X such as the Lusternik-Schnirelmann Category of X, the index of nilpotency of ᘯ(X), the cocategory of X, the index of conilpotency of ∑ (X) have been studied by Eckmann, Hilton, Berstein and Ganea, etc. Recently D. G. Quillen [6] has developed homotopy theory for categories satisfying certain axioms. In the axiomatic set up of Quillen the duality observed in classical homotopy theory becomes a self-evident phenomenon, the axioms being so formulated.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1975

References

1. Ganea, T., Lusternik-Schnirelmann category and cocategory, Proc. Lond. Math. Soc. 10 (1960), 623639.Google Scholar
2. Ganea, T., Fibrations and cocategory, Comment. Math. Helv. 35 (1961). 1524,Google Scholar
3. Ganea, T., Sur quelques invariants numériques du type d'homotopie. Cahiers de topologie et géométrie différentielle, Ehresmann Seminar, Paris, 1962.Google Scholar
4. Hilton, P. J., Homotopy theory and duality, Lecture Notes, Cornell University, 1959.Google Scholar
5. Maclane, S., Categories for the working mathematician, (Springer-Verlag, Berlin, 1971).Google Scholar
6. Quillen, D. G., Homotopical algebra, Springer Lecture Notes 43, 1967.Google Scholar
7. G. W., Whitehead, The homology suspension, Colloque de Topologie Algébrique, Louivan 1956, pp. 8995.Google Scholar
8. Whitehead, J. H. C., Combinatorial homotopy, I, Bull. Amer. Math. Soc. 55 (1949), 213245.Google Scholar