Let H be a Hilbert space and M be a closed linear subspace of H. Then by projection theorem H = M ⊕ M ⊥ . This theorem suggests that the result has something to do about a notion in Hilbert spaces which is analogous to and a generalization of the familiar idea of Orthogonal or pe...
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Research Article10.9734/jamcs/2022/v37i330440
The concept of a compact operator on a Hilbert space, H is an extension of the concept of a matrix acting on a finite-dimensional vector space. In Hilbert space, compact operators are precisely the closure of finite rank operators in the topology induced by the operator norm. In...
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Research Article10.9734/jamcs/2022/v37i330438
Let X be a Complex Banach space and T be a bounded operator in X. The number sup {|λ| : λ ∈ σ(T)} (where σ(T) is the spectrum of T and σ(T) ̸= ϕ) is called the spectral radius of T and denoted by r(T). Since λ ≤ ∥T∥for all λ ∈ σ(T), it follows that r(T) ≤ ∥T∥. The spectral mappin...
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Research Article10.9734/arjom/2022/v18i130353
Analytic dependence on a complex parameter appears at many places in the study of differential and integral equations. The display of analyticity in the solution of the Fredholm equation of the second kind is an early signal of the important role which analyticity was destined to...
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Research Article10.9734/jamcs/2021/v36i1030407
The spectral properties of a compact operator \(T : X \longrightarrow Y\) on a normed linear space resemble those of square matrices. For a compact operator, the spectral properties can be treated fairly completely in the sense that Fredholm's famous theory of integral equations...
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Research Article10.9734/arjom/2022/v18i830397
It is possible to express all geometric notions connected with closed linear subspaces in terms of algebraic properties of the orthoprojectors onto these linear spaces. In this paper, sufficient conditions for the calculus of a family of orthoprojectors in B(H) have been given wi...
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Research Article10.9734/arjom/2022/v18i830394