English

Gorin's problem for individual simple partial fractions

Classical Analysis and ODEs 2019-07-23 v2

Abstract

The main result of the paper is a lower estimate for the moduli of imaginary parts of the poles of a simple partial fraction (i.e. the logarithmic derivative of an algebraic polynomial) under the condition that the L(R)L^\infty(\mathbb{R})-norm of the fraction is unit (Gorin's problem). In contrast to the preceding results, the estimate takes into account the residues associated with the poles. Moreover, a new estimate for the moduli is obtained in the case when the L(R)L^\infty(\mathbb{R})-norm of the derivative of the simple partial fraction is unit (Gelfond's problem).

Keywords

Cite

@article{arxiv.1907.07437,
  title  = {Gorin's problem for individual simple partial fractions},
  author = {Petr Chunaev and Vladimir Danchenko},
  journal= {arXiv preprint arXiv:1907.07437},
  year   = {2019}
}

Comments

Corrected several misprints

R2 v1 2026-06-23T10:23:02.310Z