Exponentially-improved asymptotics for $q$-difference equations: ${}_2\phi_0$ and $q{\rm P}_{\rm I}$
Classical Analysis and ODEs
2024-03-05 v1
Abstract
Usually when solving differential or difference equations via series solutions one encounters divergent series in which the coefficients grow like a factorial. Surprisingly, in the -world the th coefficient is often of the size , in which is fixed. Hence, the divergence is much stronger, and one has to introduce alternative Borel and Laplace transforms to make sense of these formal series. We will discuss exponentially-improved asymptotics for the basic hypergeometric function and for solutions of the -difference first Painlev\'e equation . These are optimal truncated expansions, and re-expansions in terms of new -hyperterminant functions. The re-expansions do incorporate the Stokes phenomena.
Cite
@article{arxiv.2403.02196,
title = {Exponentially-improved asymptotics for $q$-difference equations: ${}_2\phi_0$ and $q{\rm P}_{\rm I}$},
author = {Nalini Joshi and Adri Olde Daalhuis},
journal= {arXiv preprint arXiv:2403.02196},
year = {2024}
}
Comments
15 pages, 1 figure