Results 11 to 20 of about 96,721 (176)
Two-state intermittency near a symmetric interaction of saddle-node and Hopf bifurcations: a case study from dynamo theory [PDF]
We consider a model of a Hopf bifurcation interacting as a codimension 2 bifurcation with a saddle-node on a limit cycle, motivated by a low-order model for magnetic activity in a stellar dynamo.
Alastair M. Rucklidge +24 more
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Invariant Subspaces, Quasi-invariant Subspaces, and Hankel Operators
The authors study algebraic properties of small Hankel operators on Bergman spaces of bounded symmetric domains \(\Omega\subset \mathbb{C}^n\). Here, the Bergman space \(L^2_a(\Omega)\) is the closed subspace of \(L^2(\Omega)\) consisting of analytic functions and the small Hankel operator \(\Gamma_\varphi\) with symbol \(\varphi\in L^2(\Omega)\) is ...
Guo, Kunyu, Zheng, Dechao
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We provide upper bounds on the perturbation of invariant subspaces of normal matrices measured using a metric on the space of vector subspaces of C n $\mathbb{C}^{n}$ in terms of the spectrum of both unperturbed and perturbed matrices as well as the ...
Subhrajit Bhattacharya
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Modeling Sampling in Tensor Products of Unitary Invariant Subspaces
The use of unitary invariant subspaces of a Hilbert space H is nowadays a recognized fact in the treatment of sampling problems. Indeed, shift-invariant subspaces of L2(R) and also periodic extensions of finite signals are remarkable examples where this ...
Antonio G. García +2 more
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Isometries of ∗ -Invariant Subspaces [PDF]
We consider families of increasing ∗ ^\ast -invariant subspaces of H 2 ( D ) {H^2}(D) , and from these we construct canonical isometrics from certain L 2 {L^2} spaces to
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An invariant subspace problem for multilinear operators on Banach spaces and algebras
This paper is concerned with the study of invariant subspace problems for nonlinear operators on Banach spaces/algebras. Our study reveals that one faces unprecedented challenges such as lack of vector space structure and unbounded spectral sets when ...
John Emenyu
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The invariant subspaces of S ⊕ S*
Using the tools of Sz.-Nagy–Foias theory of contractions, we describe in detail the invariant subspaces of the operator S ⊕ S*, where S is the unilateral shift on a Hilbert space. This answers a question of Câmara and Ross.
Timotin Dan
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Invariant Subspaces: An Alternative for Introducing Eigenvectors and Eigenvalues
The concepts of eigenvalue and eigenvector are typically approached algorithmically in introductory linear algebra courses. However, a more conceptual orientation involves connecting these notions to the concept of one-dimensional invariant subspace ...
Gisela Camacho, Asuman Oktaç
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Quasi-exact solvability in a general polynomial setting [PDF]
Our goal in this paper is to extend the theory of quasi-exactly solvable Schrodinger operators beyond the Lie-algebraic class. Let $\cP_n$ be the space of n-th degree polynomials in one variable.
Gomez-Ullate, David +2 more
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Proper contractions and invariant subspaces
Let T be a contraction and A the strong limit of {T∗nTn}n≥1. We prove the following theorem: if a hyponormal contraction T does not have a nontrivial invariant subspace, then T is either a proper contraction of class 𝒞00 or a nonstrict proper contraction
C. S. Kubrusly, N. Levan
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