In this paper, we prove that every unbounded linear operator satisfying the Korotkov-Weidmann characterization is unitarily equivalent to an integral operator in L 2(R), with a bounded and infinitely smooth Carleman kernel. The established unitary equivalence is implemented by explicitly definable unitary operators.
@article{bwmeta1.element.doi-10_2478_BF02475625,
author = {Igor Novitski\^\i },
title = {Integral representations of unbounded operators by infinitely smooth kernels},
journal = {Open Mathematics},
volume = {3},
year = {2005},
pages = {654-665},
zbl = {1118.47039},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_BF02475625}
}
Igor Novitskiî. Integral representations of unbounded operators by infinitely smooth kernels. Open Mathematics, Tome 3 (2005) pp. 654-665. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_BF02475625/
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