Skip to main content
Log in

Der beschränkte Fall des gewichteten Approximationsproblems für vektorwertige Funktionen

  • Published:
manuscripta mathematica Aims and scope Submit manuscript

Abstract

Let W be a linear subspace of a weighted space of type CV(X,E) and an A-module (A being a subalgebra of C(X)). The weighted approximation problem, as formulated by L. Nachbin [12] in the case E =\(\mathbb{K}\) and for W⊂CVo(X), asks for a description of the closure of W. In its bounded case (see [12]) a general answer was given by W.H. Summers [20] for W⊂CVo(X) which is, under certain additional assumptions on X and V, also valid for W⊂CVo(X,E) as J.B. Prolla [15] had already proved. By extending the methods developed in [10] it is shown in this paper that these results can be generalized to arbitrary X,V and E, and moreover, that by considering compactifications of X similar solutions can be found for subspaces of CV(X,E). Applying them to a result of K.-D. Bierstedt [2] the approximation property of (certain subspaces of) CV(X) can be derived. As a further application tensor products of weighted spaces are investigated.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Literatur

  1. BIERSTEDT, K.-D.: Gewichtete Räume stetiger vektorwertiger Funktionen und das injektive Tensorprodukt. I. J.f.d. reine u. angew. Math.259, 186–210 (1973)

    Google Scholar 

  2. —: Gewichtete Räume stetiger vektorwertiger Funktionen und das injektive Tensorprodukt. II. J.f.d. reine u. angew. Math.260, 133–146 (1973)

    Google Scholar 

  3. —: Injektive Tensorprodukte und Slice-Produkte gewichteter Räume stetiger Funktionen. J.f.d. reine u. angew. Math.266, 121–131 (1974)

    Google Scholar 

  4. -: The approximation property for weighted function spaces. to appear in Bonner Math. Schriften (Proc. Conference Bonn, 1974)

  5. -: Tensor products of weighted spaces, to appear in Bonner Math. Schriften (Proc. Conference Bonn, 1974)

  6. BUCHWALTER, H.: Topologies et compactologies. Publ. Dépt. Math. Lyon6–2, 1–74 (1969)

    Google Scholar 

  7. DINCULEANU, N.: Vector measures. 1. Aufl. Berlin: VEB Deutscher Verlag der Wissenschaften 1967

    Google Scholar 

  8. FUCHSSTEINER, B.: Sandwich theorems and lattice semi-groups. J. Functional Analysis16, 1–14 (1974)

    Google Scholar 

  9. GLICKSBERG, I.: Stone-Čech compactifications of products. Trans. Amer. Math. Soc.90, 369–382 (1959)

    Google Scholar 

  10. KLEINSTÜCK, G.: Duals of weighted spaces of continuous functions. to appear in Bonner Math. Schriften (Proc. Conference Bonn, 1974)

  11. KÖNIG, H.: Sublineare Funktionale. Arch. Math.23, 500–508 (1972)

    Google Scholar 

  12. NACHBIN, L.: Weighted approximation for algebras and modules of continuous functions: real and self-adjoint complex cases. Ann. of Math.81, 289–302 (1965)

    Google Scholar 

  13. —: Elements of approximation theory. First ed. Princeton-Toronto-London-Melbourne: Van Nostrand Company (1967)

    Google Scholar 

  14. PROLLA, J.B.: Weighted spaces of vector-valued continuous functions. Ann. Mat. Pura Appl. (4)89, 145–158 (1971)

    Google Scholar 

  15. —: Bishop's generalized Stone-Weierstrass theorem for weighted spaces. Math. Ann.191, 283–289 (1971)

    Google Scholar 

  16. —: The weighted Dieudonné theorem for density in tensor products. Indag. Math.33, 170–175 (1971)

    Google Scholar 

  17. SUMMERS, W.H.: A representation theorem for biequicontinuous completed tensor products of weighted spaces. Trans. Amer. Math. Soc.146, 121–132 (1969)

    Google Scholar 

  18. —: Dual spaces of weighted spaces. Trans. Amer. Math. Soc.151, 323–333 (1970)

    Google Scholar 

  19. SUMMERS, W.H.: The bounded case of the weighted approximation problem. p. 177–183 in “Functional analysis and applications (Symposium Recife, Brasil 1972)”, Springer Lecture Notes in Math.384 (1974)

  20. -: Weighted approximation for modules of continuous functions II. Proc. Symp. Rio de Janeiro (1972), to appear (Hermann, Paris)

  21. -: to appear (cf. Abstracts of Communications, Intern. Congress of Math., Vancouver, 1974)

  22. BIERSTEDT, K.-D., GRAMSCH, B., MEISE, R.: erscheint noch

  23. NACHBIN, L., MACHADO, S., PROLLA, J.B.: Weighted approximation, vector fibrations and algebras of operators. J. Math. pures et appl.50, 299–323 (1971)

    Google Scholar 

  24. BUCHWALTER, H.: Produit topologique, produit tensoriel et c-repletion. Bull. Soc. math. France, Mém.31–32, 51–71 (1972)

    Google Scholar 

  25. PUPIER, R.: Méthodes fonctorielles en topologie générale. Thèse Fac. Sc. Lyon, 1–121 (1971)

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kleinstück, G. Der beschränkte Fall des gewichteten Approximationsproblems für vektorwertige Funktionen. Manuscripta Math 17, 123–149 (1975). https://doi.org/10.1007/BF01154086

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01154086

Navigation