43 citations · 194 across the 50 of their papers we have counts for
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Finite difference operators with a finite--band spectrum
F. Peherstorfer, P. Yuditskii
We study the correspondence between almost periodic difference operators and algebraic curves (spectral surfaces). An especial role plays the parametrization of the spectral curves…
Uniform approximation of sgn(x) by rational functions with prescribed poles
Franz Peherstorfer, Peter Yuditskii
For let be the error of the best approximation of the function $\sgn(x)$ on the two symmetric intervals by rational functions with the on…
Uniform approximation of sgn(x) by polynomials and entire functions
Alexandre Eremenko, Peter Yuditskii
We study the best uniform approximation by polynomials of fixed degree of the function sgn(x) on the union of two intervals symmetric with respect to the origin. We obtain precise…
Spectral Properties of a Class of Reflectionless Schrödinger Operators
Fritz Gesztesy, Peter Yuditskii
We prove that one-dimensional reflectionless Schrödinger operators with spectrum a homogeneous set in the sense of Carleson, belonging to the class introduced by Sodin and Yuditski…