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The Fourier transform of vector-valued functions

Published online by Cambridge University Press:  18 May 2009

Susumu Okada
Affiliation:
Department of Mathematical Sciences, San Diego State University, San Diego, CA 92182-0314, U.S.A.
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For each natural number n, let un(x)=(1—cos nx)/πnx2(xɛℝ). It is well–known that a bounded continuous function f on the real line ℝ is the Fourier transform of an integrable function on ℝ if and only if the functions Φn(f) (n= 1, 2,…), defined by

form a Cauchy sequence in the space L1(ℝ) (cf. [2]). Such a characterization, which can be extended to functions defined on a locally compact Abelian group more general than ℝ, is based on the fact that the space L1(ℝ) is complete with respect to convergence in mean.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1985

References

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