Approximation theory for matrices
نویسندگان
چکیده
منابع مشابه
Approximation Theory for Matrices
There are many situations in which it is desirable to evaluate a function of a matrix. For instance, in lattice quantum field theory it is sometimes desirable to evaluate the square root of a discretised Dirac operator D/ in order to calculate the effects of varying the number of fermionic flavours [1,2,3,4,5], or to construct a good approximation to Neuberger’s operator for GinspargWilson ferm...
متن کاملApproximation of matrices
We improve here two results from the preprints [DK], [AFKK] on approximating matrices by random submatrices. We use a construction of a random subset of a finite set, which is different from what was suggested in [AFKK]. Instead of taking a random q-element subset of an n-element set, we consider independent {0, 1}-valued random variables δ1, . . . , δn, taking value 1 with probability δ = q/n....
متن کاملApproximation Results for Reflectionless Jacobi Matrices
We study spaces of reflectionless Jacobi matrices. The main theme is the following type of question: Given a reflectionless Jacobi matrix, is it possible to approximate it by other reflectionless and, typically, simpler Jacobi matrices of a special type? For example, can we approximate by periodic operators?
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در این پایان نامه یک مولد برای چند قاب یا ابر قاب تولید شده تحت عمل نمایش یکانی تصویر برای گروه های شمارش پذیر گسسته بررسی خواهد شد. مثال هایی از این قاب ها چند قاب های گابور، ابرقاب های گابور و قاب هایی برای زیرفضاهای انتقال پایاست. نشان می دهیم که مولد چند قاب تنک نرمال شده (ابرقاب) یکتا وجود دارد به طوری که مینیمم فاصله را از ان دارد. همچنین مسایل مشابه برای قاب های دوگان مطرح شده و برخی ...
15 صفحه اولAnalysis of Some Krylov Subspace Methods for Normal Matrices via Approximation Theory and Convex Optimization
Krylov subspace methods are strongly related to polynomial spaces and their convergence analysis can often be naturally derived from approximation theory. Analyses of this type lead to discrete min-max approximation problems over the spectrum of the matrix, from which upper bounds of the relative Euclidean residual norm are derived. A second approach to analyzing the convergence rate of the GMR...
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ژورنال
عنوان ژورنال: Nuclear Physics B - Proceedings Supplements
سال: 2004
ISSN: 0920-5632
DOI: 10.1016/s0920-5632(03)02466-6