English

Stokes matrices for a class of reducible equations

Classical Analysis and ODEs 2019-06-25 v1

Abstract

This paper is a continuation of our previous work \cite{St} where we have studied the Stokes phenomenon for a particular family of equation \eqref{initial} with \eqref{form-0}-\eqref{npe} from a perturbative point of view. Here we focus on the explicit computation of the Stokes matrices at the non-resonant irregular singularity for a more general situation. In particular, utilizing Borel-Laplace summation, the iterated integrals approach and some properties of the hypergeometric series we compute by hand the Stokes matrices of three families of equation \eqref{initial}-\eqref{form-0}-\eqref{npe} under assumptions that βj\beta_j's are distinct and β3β1<β3β2|\beta_3-\beta_1| < |\beta_3-\beta_2|. Moreover, these results remain valid for these distinct βj\beta_j's for which β3β1=β3β2|\beta_3-\beta_1|=|\beta_3-\beta_2| but β3β1±(β3β2)\beta_3-\beta_1 \neq \pm (\beta_3-\beta_2) on condition that Re(α2α1)>1\mathcal{Re} (\alpha_2-\alpha_1) > -1. In addition, iterated integrals approach allows us to give, under some restrictions, an explicit representation of the 1-sum of the product of two certain divergent 1-summable power series, that have different singular directions.

Keywords

Cite

@article{arxiv.1906.09747,
  title  = {Stokes matrices for a class of reducible equations},
  author = {Tsvetana Stoyanova},
  journal= {arXiv preprint arXiv:1906.09747},
  year   = {2019}
}