Results 21 to 30 of about 90,779 (292)
Linear maps preserving $A$-unitary operators [PDF]
Mathematica Bohemica, 2016 Let $\mathcal{H}$ be a complex Hilbert space, $A$ a positive operator with closed range in $\mathscr{B}(\mathcal{H})$ and $\mathscr{B}_A(\mathcal{H})$ the sub-algebra of $\mathscr{B}(\mathcal{H})$ of all $A$-self-adjoint operators. Assume $\phi \mathscr{
Abdellatif Chahbi +2 more
doaj +1 more source
A New Semi-Inner Product and pn-Angle in the Space of p-Summable Sequences
Mathematics, 2023 In this paper, we propose a definition for a semi-inner product in the space of p-summable sequences equipped with an n-norm. Using this definition, we introduce the concepts of pn-orthogonality and the pn-angle between two vectors in the space of p ...
Muh Nur +3 more
doaj +1 more source
On the uniqueness of minimal projections in Banach spaces [PDF]
Opuscula Mathematica, 2012 Let \(X\) be a uniformly convex Banach space with a continuous semi-inner product. We investigate the relation of orthogonality in \(X\) and generalized projections acting on \(X\). We prove uniqueness of orthogonal and co-orthogonal projections.
Ewa Szlachtowska, Dominik Mielczarek
doaj +1 more source
Semi-inner-product spaces [PDF]
Transactions of the American Mathematical Society, 1961 function as a particular Banach space (whose norm satisfies the parallelogram law), but rather as an inner-product space. It is in terms of the innerproduct space structure that most of the terminology and techniques are developed. On the other hand, this type of Hilbert space considerations find no real parallel in the general Banach space setting ...
openaire +2 more sources
On The Adjoint of Bounded Operators On A Semi-Inner Product Space
Journal of the Indonesian Mathematical Society, 2023 The notion of semi-inner product (SIP) spaces is a generalization of inner product (IP) spaces notion by reducing the positive definite property of the product to positive semi-definite. As in IP spaces, the existence of an adjoint of a linear operator on a SIP space is guaranteed when the operator is bounded.
Respitawulan, R. +4 more
openaire +1 more source
Spectral expansions of open and dispersive optical systems: Gaussian regularization and convergence
New Journal of Physics, 2021 Resonant states (RS), also known as quasi-normal modes, arise in spectral expansions of linear response functions of open systems. Manipulation of these spatially ‘divergent’ oscillating functions requires a departure from the usual definitions of inner ...
B Stout, R Colom, N Bonod, R C McPhedran
doaj +1 more source
Axioms, 2023 This work aims to develop a new class of accretive mappings and investigate its associated class of proximal mappings. This new class of accretive mappings is known as generalized (Hk,φ)-η-accretive mappings.
Sanjeev Gupta, Nifeen Hussain Altaweel
doaj +1 more source
Hypo-q-Norms on a Cartesian Product of Algebras of Operators on Banach Spaces
Annales Mathematicae Silesianae, 2020 In this paper we consider the hypo-q-operator norm and hypo-q-numerical radius on a Cartesian product of algebras of bounded linear operators on Banach spaces.
Dragomir Silvestru Sever
doaj +1 more source
On semi inner product spaces over quaternions [PDF]
Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics, 1984 AbstractIn this note semi inner product spaces over quaternions are studied. We investigate the properties of complex strict convexity over C, left and right Q-complex strict convexity over Q, and left and right quaternion strict convexity. Finally we discuss the permanence properties with respect to formation of products.
openaire +2 more sources
Improved estimates for the triangle inequality
Journal of Inequalities and Applications, 2017 We obtain refined estimates of the triangle inequality in a normed space using integrals and the Tapia semi-product. The particular case of an inner product space is discussed in more detail.
Nicuşor Minculete, Radu Păltănea
doaj +1 more source