On continuity of the variation and the Fourier transform
Maserick, P. H.
Illinois J. Math., Tome 29 (1985) no. 4, p. 302-310 / Harvested from Project Euclid
Let $S$ be a commutative semitopological semigroup with identity and involution, $\Gamma$ a compact subset in the topology of pointwise convergence of the set of semicharacters on $S$. Let $f$ be a function which admits a (necessarily unique) integral representation of the form $$f(s)=\int_{\Gamma}{\rho(s)d\mu_{f}(\rho)}\quad (\rho \in \Gamma,s \in S$$ with respect to a complex regular Borel measure $\mu_{f}$ on $\Gamma$. The function $|f|(\cdot)$ defined by $|f|(s)=\int_{\Gamma}{\rho(s)d|\mu_{f}|}$ is called the variation of $f$. It is shown that the variation $|f|$ is bounded and continuous if and only if $f$ is also bounded and continuous. This, coupled with the author's previous characterization of functions of bounded variation, gives a new description of the Fourier transforms of bounded measures on locally compact commutative groups.
Publié le : 1985-06-15
Classification:  43A35,  44A60
@article{1256045731,
     author = {Maserick, P. H.},
     title = {On continuity of the variation and the Fourier transform},
     journal = {Illinois J. Math.},
     volume = {29},
     number = {4},
     year = {1985},
     pages = { 302-310},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1256045731}
}
Maserick, P. H. On continuity of the variation and the Fourier transform. Illinois J. Math., Tome 29 (1985) no. 4, pp.  302-310. http://gdmltest.u-ga.fr/item/1256045731/