Exact constants in approximation theory
نویسندگان
چکیده
منابع مشابه
Exact results for some Madelung type constants in the finite-size scaling theory
A general formula is obtained from which the Madelung type constant: C(d|ν) = ∞ 0 dxx d/2−ν−1 ∞ l=−∞ e −xl 2 d − 1 − π x d 2 extensively used in the finite-size scaling theory is computed analytically for some particular cases of the parameters d and ν. By adjusting these parameters one can obtain different physical situations corresponding to different geometries and magnitudes of the ...
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There is a discussion between L. B. Okun, G. Veneziano and M. J. Duff, concerning the number of fundamental dimensionful constants in physics [1]. They advocated correspondingly 3, 2 and 0 fundamental constants. Here we consider this problem on example of the effective relativistic quantum field theory, which emerges in the low energy corner of quantum liquids and which reproduces many features...
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Quadratic Stark constants of neutral copper spectral lines for all s,p, and d levels are calculated using the Coulomb approximation. These results are compared with existing data and, generally, good agreement is observed
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We show that the saturation order of piecewise constant approximation in Lp norm on convex partitions with N cells is N −2/(d+1), where d is the number of variables. This order is achieved for any f ∈ W 2 p (Ω) on a partition obtained by a simple algorithm involving an anisotropic subdivision of a uniform partition. This improves considerably the approximation order N−1/d achievable on isotropi...
متن کاملExact Solutions in Structured Low-Rank Approximation
Structured low-rank approximation is the problem of minimizing a weighted Frobenius distance to a given matrix among all matrices of fixed rank in a linear space of matrices. We study the critical points of this optimization problem using algebraic geometry. A particular focus lies on Hankel matrices, Sylvester matrices and generic linear spaces.
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 1992
ISSN: 0021-9045
DOI: 10.1016/0021-9045(92)90073-w