Fractal dimensions of spectral measures of rank one perturbations of a positive self-adjoint operator

Rank one perturbations of self-adjoint operators

On Rank One H−3-Perturbations of Positive Self–adjoint Operators

Rank one H−3 perturbations of positive self–adjoint operators are constructed using a certain extended Hilbert space and regularization procedures. Applications to Schrödinger operators with point interactions are discussed.

Spectral Behaviour of a Simple Non-self-adjoint Operator

We investigate the spectrum of a typical non-selfadjoint differential operator AD = −d2/dx2 ⊗ A acting on L(0, 1) ⊗ C, where A is a 2 × 2 constant matrix. We impose Dirichlet and Neumann boundary conditions in the first and second coordinate respectively at both ends of [0, 1] ⊂ R. For A ∈ R we explore in detail the connection between the entries of A and the spectrum of AD, we find necessary c...

Spectral properties of unbounded JJ-self-adjoint block operator matrices

We study the spectrum of unbounded J-self-adjoint block operator matrices. In particular, we prove enclosures for the spectrum, provide a sufficient condition for the spectrum being real and derive variational principles for certain real eigenvalues even in the presence of non-real spectrum. The latter lead to lower and upper bounds and asymptotic estimates for eigenvalues. AMS Subject classifi...

a comparison of linguistic and pragmatic knowledge: a case of iranian learners of english

در این تحقیق دانش زبانشناسی و کاربردشناسی زبان آموزان ایرانی در سطح بالای متوسط مقایسه شد. 50 دانش آموز با سابقه آموزشی مشابه از شش آموزشگاه زبان مختلف در دو آزمون دانش زبانشناسی و آزمون دانش گفتار شناسی زبان انگلیسی شرکت کردند که سوالات هر دو تست توسط محقق تهیه شده بود. همچنین در این تحقیق کارایی کتابهای آموزشی زبان در فراهم آوردن درون داد کافی برای زبان آموزان ایرانی به عنوان هدف جانبی تحقیق ...