Article
Keywords:
Ostrowski’s type inequalities; Riemann-Stieltjes integral inequalities; unitary operators in Hilbert spaces; spectral theory; quadrature rules
Summary:
Some Ostrowski’s type inequalities for the Riemann-Stieltjes integral $\int _{a}^{b}f\left( e^{it}\right) du\left( t\right) $ of continuous complex valued integrands $f\colon \mathcal{C}\left( 0,1\right) \rightarrow \mathbb{C}$ defined on the complex unit circle $\mathcal{C}\left( 0,1\right) $ and various subclasses of integrators $u\colon \left[ a,b\right] \subseteq \left[ 0,2\pi \right] \rightarrow \mathbb{C}$ of bounded variation are given. Natural applications for functions of unitary operators in Hilbert spaces are provided as well.
References:
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Zbl 0969.26017
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MR 0243367 |
Zbl 0177.42401
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DOI 10.1007/BF01214290 |
MR 1509574