Abstract
We construct a totally disconnected ω*, norming subsetF of the unit ballB * of an arbitrary separable Banach space,X, and an operator fromC(F) toC(B*) that “amost” commutes with the natural embeddings ofX. This is used to give a new proof of Milutin's theorem and to prove some new results on complemented subspaces ofC[0, 1] with separable dual. In particular we show that a complemented subspace ofC(ωω), is either isomorphic toC(ωω) or toc u.
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References
D. E. Alspach,Quotients of C[0, 1]with separable dual, to appear.
Y. Benyamini and J. Lindenstrauss,A predual of l 1 which is not isomorphic to a C(K)-space, Israel J. Math.13 (1972), 246–259.
C. Bessaga and A. Pelczynski,Spaces of continuous functions IV, Studia Math.19 (1960), 53–62.
S. Z. Ditor,On a lemma of Milutin concerning averaging operators in continuous function spaces, Trans. Amer. Math. Soc.149 (1970), 443–452.
W. B. Johnson and M. Zippin,On subspaces of quotients of (ΣG n)l p and (ΣGn)c o, Israel J. Math.13 (1972), 311–316.
J. Lindenstrauss and L. Tzafriri,Classical Banach spaces, Springer-Verlag Lecture Notes in Mathematics338 (1973).
S. Mazurkiewicz and W. Sierpinski,Contribution à la topologie des ensembles dénomrables, Fund. Math.1 (1920), 17–27.
A. A. Milutin,Isomorphisms of spaces of continuous functions on compacta of power continuum, Tieoria Func. (Kharkov)2 (1966), 150–156 (Russian).
A. Pelczynski,Linear extensions, linear averaging and their application to linear topological classification of spaces of continuous functions, Rozprawy Mathematyczne58 (1968).
W. Szlenk,The non-existence of a separable reflexive Banach space, universal for all separable reflexive Banach spaces, Studia Math.30 (1968), 53–61.
M. Zippin,The separable extension problem, Israel J. Math.26 (1977), 372–387.
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Benyamini, Y. An extension theorem for separable Banach spaces. Israel J. Math. 29, 24–30 (1978). https://doi.org/10.1007/BF02760399
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DOI: https://doi.org/10.1007/BF02760399