Currently displaying 1 – 5 of 5

Showing per page

Order by Relevance | Title | Year of publication

The truncated matrix trigonometric moment problem with an open gap

Sergey Zagorodnyuk — 2015

Concrete Operators

This paper is a continuation of our previous investigations on the truncated matrix trigonometric moment problem in Ukrainian Math. J., 2011, 63, no. 6, 786-797, and Ukrainian Math. J., 2013, 64, no. 8, 1199- 1214. In this paper we shall study the truncated matrix trigonometric moment problem with an additional constraint posed on the matrix measure MT(δ), δ ∈ B(T), generated by the seeked function M(x): MT(∆) = 0, where ∆ is a given open subset of T (called a gap). We present necessary and sufficient...

Density of Polynomials in the L^2 Space on the Real and the Imaginary Axes and in a Sobolev Space

Klotz, Lutz;  Zagorodnyuk, Sergey M. — 2009

Serdica Mathematical Journal

2000 Mathematics Subject Classification: 41A10, 30E10, 41A65. In this paper we consider an L^2 type space of scalar functions L^2 M, A (R u iR) which can be, in particular, the usual L^2 space of scalar functions on R u iR. We find conditions for density of polynomials in this space using a connection with the L^2 space of square-integrable matrix-valued functions on R with respect to a non-negative Hermitian matrix measure. The completness of L^2 M, A (R u iR ) is also established.

Page 1

Download Results (CSV)