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Indices of Function Spaces and theirRelationship to Interpolation

Published online by Cambridge University Press:  20 November 2018

David W. Boyd*
Affiliation:
California Institute of Technology, Pasadena, California
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A special case of the theorem of Marcinkiewicz states that if T is a linear operator which satisfies the weak-type conditions (p, p) and (q,q), then T maps Lr continuously into itself for any r with p < r < q. In a recent paper (5), as part of a more general theorem, Calderόn has characterized the spaces X which can replace Lr in the conclusion of this theorem, independent of the operator T. The conditions which X must satisfy are phrased in terms of an operator S(σ) which acts on the rearrangements of the functions in X.

One of Calderόn's results implies that if X is a function space in the sense of Luxemburg (9), then X must be a rearrangement-invariant space.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1969

References

1. Boyd, D. W., The Hilbert transform on rearrangement-invariant spaces. Can. J. Math. 19 (1967), 599616 Google Scholar
2. Boyd, D. W., The spectral radius of averaging operators, Pacific J. Math. 24 (1968), 1928.Google Scholar
3. Boyd, D. W., Monotone semigroups of operators on cones, Can. Math. Bull. 12 (1969), 299310.Google Scholar
4. Boyd, D. W., Indices and exponents for Orlicz spaces (unpublished manuscript).Google Scholar
5. Calderon, A. P., Spaces between L1 and L°° and the theorem of Marcinkiewicz, Studia Math. 26 (1966), 273299.Google Scholar
6. Halmos, P., Measure theory (Van Nostrand, New York, 1950).Google Scholar
7. Hille, E. and Phillips, R. S., Functional analysis and semi-groups, Amer. Math. Soc. Colloq. Publ., Vol. 31, rev. éd. (Amer. Math. Soc, Providence, R.I., 1957).Google Scholar
8. Lorentz, G. G., Some new functional spaces, Ann. of Math. (2) 51 (1950), 3755.Google Scholar
9. Luxemburg, W. A. J., Banach function spaces, Thesis, Delft Technical University, 1955.Google Scholar
10. Luxemburg, W. A. J., Rearrangement-invariant Banach function spaces, Queen's papers in Pure and Applied Mathematics 10 (1967), 83144, Queen's University, Canada.Google Scholar
11. Stein, E. M. and Weiss, G., An extension of a theorem of Marcinkiewicz and some of its applications, J. Math. Mech. 8 (1959), 263284.Google Scholar
12. Zygmund, A., Trigonometric series, Vol. II (Cambridge, at the University Press, 1959).Google Scholar