Results 21 to 30 of about 2,806 (244)
Variational characterizations for eigenfunctions of analytic self-adjoint operator functions [PDF]
Opuscula Mathematica, 2013 In this paper we consider Rellich's diagonalization theorem for analytic self-adjoint operator functions and investigate variational principles for their eigenfunctions and interlacing statements.
Georgios Katsouleas, John Maroulas
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Equality Between the Spectrum of PT-Symmetric Shrödinger Operators and Their Adjoint
MathematicsIn classical spectral theory, self-adjoint differential operators satisfy the relation σ(L)=σ(L∗). However, this is not necessarily true for non-self-adjoint operators.
Ece Özdemir, Alp Arslan Kıraç
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Self-adjoint curl operators [PDF]
Annali di Matematica Pura ed Applicata, 2011 We study the exterior derivative as a symmetric unbounded operator on square integrable 1-forms on a 3D bounded domain $D$. We aim to identify boundary conditions that render this operator self-adjoint. By the symplectic version of the Glazman-Krein-Naimark theorem this amounts to identifying complete Lagrangian subspaces of the trace space of H(curl ...
Hiptmair, Ralf +2 more
openaire +5 more sources
Correspondence of the eigenvalues of a non-self-adjoint operator to those of a self-adjoint operator [PDF]
, 2008 We prove that the eigenvalues of a certain highly non-self-adjoint operator that arises in fluid mechanics correspond, up to scaling by a positive constant, to those of a self-adjoint operator with compact resolvent; hence there are infinitely many real ...
John Weir
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Weyl-Titchmarsh theory for Sturm-Liouville operators with distributional potentials [PDF]
Opuscula Mathematica, 2013 We systematically develop Weyl-Titchmarsh theory for singular differential operators on arbitrary intervals \((a,b) \subseteq \mathbb{R}\) associated with rather general differential expressions of the type \begin{equation*}\tau f = \frac{1}{\tau} (-(p[f'
Jonathan Eckhardt +3 more
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The Canadian Journal of Chemical Engineering, EarlyView.Abstract We develop a delay‐aware estimation and control framework for a non‐isothermal axial dispersion tubular reactor modelled as a coupled parabolic‐hyperbolic PDE system with recycle‐induced state delay. The infinite‐dimensional dynamics are preserved without spatial discretization by representing the delay as a transport PDE and adopting a late ...
Behrad Moadeli, Stevan Dubljevic
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Operators on Soft Inner Product Spaces
Fuzzy Information and Engineering, 2014 In the present paper, self-adjoint operator and completely continuous operator on soft inner product spaces have been introduced and some basic properties of such operators are studied.
Sujoy Das, S.K. Samanta
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Comptes Rendus. Mathématique, 2022 In this paper we perform the analysis of the spectrum of a degenerate operator $A_\varepsilon $ corresponding to the stationary heat equation in a $\varepsilon $-periodic composite medium having two components with high contrast diffusivity.
Sili, Ali
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The Huang–Yang Formula for the Low‐Density Fermi Gas: Upper Bound
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT We study the ground state energy of a gas of spin 1/2$1/2$ fermions with repulsive short‐range interactions. We derive an upper bound that agrees, at low density ϱ$\varrho$, with the Huang–Yang conjecture. The latter captures the first three terms in an asymptotic low‐density expansion, and in particular the Huang–Yang correction term of order
Emanuela L. Giacomelli +3 more
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Spectral Multipliers of Self-Adjoint Operators on Besov and Triebel–Lizorkin Spaces Associated to Operators [PDF]
International mathematics research notices, 2018 Let $X$ be a space of homogeneous type and let $L$ be a nonnegative self-adjoint operator on $L^2(X)$ that satisfies a Gaussian estimate on its heat kernel.
T. A. Bui, X. Duong
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