Results 11 to 20 of about 171 (46)
On new strong versions of Browder type theorems
Open Mathematics, 2018 An operator T acting on a Banach space X satisfies the property (UWΠ) if σa(T)∖ σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $(T) = Π(T), where σa(T) is the approximate point spectrum of T, σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $
Sanabria José +4 more
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Inverting a matrix function around a singularity via local rank factorization [PDF]
, 2015 This paper proposes a recursive procedure, called the extended local rank factorization (elrf), that characterizes the order of the pole and the coefficients of the Laurent series representation of the inverse of a regular analytic matrix function around
Franchi, Massimo, Paruolo, Paolo
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SVEP and local spectral radius formula for unbounded operators [PDF]
, 2014 In this paper we study the localized single valued extension property for an unbounded operator T. Moreover, we provide sufficient conditions for which the formula of the local spectral radius holds for these ...
Aiena, P., Trapani, C., Triolo, S.
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Properties of m-complex symmetric operators [PDF]
, 2017 In this paper, we study several properties of m-complex symmetric operators. In particular, we prove that if T ∈ L(H) is an m-complex symmetric operator and N is a nilpotent operator of order n > 2 with TN = NT , then T +N is a (2n+m−2)-complex ...
CHŌ, Muneo, KO, Eungil, LEE, Ji Eun
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Notes on a class of operators with the localized single-valued extension property [PDF]
, 2023 This article concerns the permanence of the single valued extension property at a point under suitableperturbations for an unbounded operatorTon a particular integrity domain.
Triolo, Salvatore
core
Early warning signs for SPDEs with continuous spectrum
European Journal of Applied MathematicsIn this work, we study early warning signs for stochastic partial differential equations (SPDEs), where the linearisation around a steady state is characterised by continuous spectrum. The studied warning sign takes the form of qualitative changes in the
Paolo Bernuzzi +2 more
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Static spectra and static families of Fredholm-type operators under tensor product
Arab Journal of Basic and Applied SciencesIn this study, we introduce the static spectrum, the Weyl static families, the upper semi-Fredholm static families, and the Browder static families. These families consist of bounded linear operators parameterized by a scalar variable.
Elvis Aponte
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Singular value decay of operator-valued differential Lyapunov and Riccati equations
, 2018 We consider operator-valued differential Lyapunov and Riccati equations, where the operators $B$ and $C$ may be relatively unbounded with respect to $A$ (in the standard notation). In this setting, we prove that the singular values of the solutions decay
Stillfjord, Tony
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Demonstratio MathematicaIf T1{{\mathbb{T}}}_{1} and T2{{\mathbb{T}}}_{2} are commuting dd-tuples of Hilbert space operators in B(ℋ)dB{\left({\mathcal{ {\mathcal H} }})}^{d} such that (T1*⊗I+I⊗T2*,T1⊗I+I⊗T2)\left({{\mathbb{T}}}_{1}^{* }\otimes I+I\otimes {{\mathbb{T}}}_{2}^{* },{
Duggal Bhagwati Prashad, Kim In Hyoun
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, 2008 In this paper, we combine results on extensions of operators with recent results on the relation between the M-function and the spectrum, to examine the spectral behaviour of boundary value problems. M-functions are defined for general closed extensions,
Amrein +35 more
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