Results 41 to 50 of about 822,201 (162)
On the eigenvalues of the lattice spin-boson model with at most one photon [PDF]
E3S Web of ConferencesIn the present paper we consider a lattice spin-boson model with at most one photon A , which has a 2×2 block operator matrix representation. The essential spectrum of A is analyzed. We prove that the operator matrix A has four eigenvalues.
Dilmurodov Elyor B. +4 more
doaj +1 more source
The Weyl essential spectrum [PDF]
Proceedings of the American Mathematical Society, 1971 Using a modest geometric hypothesis the main theorem of these results classifies the Weyl essential spectrum and the Browder essential spectrum according to the standard terminology for the spectrum of a Hilbert space operator.
openaire +2 more sources
AxiomsLet ε>0 and TB(X×X) be the Banach algebra of all 2×2 bounded upper triangular operator matrices on a separable Hilbert space X×X. In this paper, we first establish the spectrum equalities for special cases of upper triangular operator matrices—diagonal ...
Min Su, Deyu Wu
doaj +1 more source
Invariance of the essential spectrum [PDF]
Bulletin of the American Mathematical Society, 1965 Let A be a densely defined linear operator in a Banach space X. Wolf [4] defines the essential spectrum of A as the complement of §>A, the set of those complex X for which A —X is closed and (a) a(A —X), the multiplicity of X, is finite, (b) R(A —X), the range of A —X, is closed, (c) (3(A — X), the codimension of R{A — X), is finite. This set, which we
openaire +3 more sources
One-loop partition function, gauge accessibility and spectra in AdS3 gravity
Journal of High Energy Physics, 2021 We continue the study of the one-loop partition function of AdS3 gravity with focus on the square-integrability condition on the fluctuating fields. In a previous work we found that the Brown-Henneaux boundary conditions follow directly from the L 2 ...
Joel Acosta +3 more
doaj +1 more source
Symmetry, Integrability and Geometry: Methods and Applications, 2006 In this paper we formulate our results on the essential spectrum of many-particle pseudorelativistic Hamiltonians without magnetic and external potential fields in the spaces of functions, having arbitrary type α of the permutational symmetry.
Grigorii Zhislin
doaj
Essential Oils as Alternative Green Broad-Spectrum Biocides
PlantsNatural compounds from plants represent suitable options to replace synthetic biocides when employed against microorganisms in various applications. Essential oils (EOs) have attracted increased interest due to their biocompatible and rather innocuous ...
Fulga Tanasă +2 more
doaj +1 more source
The Essential Spectrum of Schrödinger, Jacobi, and CMV Operators [PDF]
Journal d'Analyse Mathématique, 2006 We provide a very general result that identifies the essential spectrum of broad classes of operators as exactly equal to the closure of the union of the spectra of suitable limits at infinity. Included is a new result on the essential spectra when potentials are asymptotic to isospectral tori.
Last, Yoram, Simon, Barry
openaire +3 more sources
Horticulturae, 2017 In recent years, consumption of herb products has increased in daily diets, contributing to the prevention of cardiovascular diseases, chronic diseases, and certain types of cancer owing to high concentrations of phytonutrients such as essential oils and
Haijie Dou +3 more
doaj +1 more source
On the location of the essential spectrum of Schrödinger operators
Proceedings of the American Mathematical Society, 2001 We give estimates on the bottom of the essential spectrum of Schrödinger operators −
METAFUNE, Giorgio Gustavo Ermanno +1 more
openaire +4 more sources