Author:
Sushchyk N. S.,Degnerys V. M.
Abstract
We study the problem of a special factorisation of an orthogonal projector~$P$ acting in the Hilbert space $L_2(\mathbb R)$ with $\dim\ker P<\infty$. In particular, we prove that the orthogonal projector~$P$ admits a special factorisation in the form$P=VV^*$, where $V$ is an isometric upper-triangular operator in the Banach algebra of all linear continuous operators in $L_2(\mathbb R)$. Moreover, wegive an explicit formula for the operator $V$.
Publisher
Ivan Franko National University of Lviv
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