Exponentially-improved asymptotics for $q$-difference equations: ${}_2\phi_0$ and $q{\rm P}_{\rm I}$

التفاصيل البيبلوغرافية
العنوان: Exponentially-improved asymptotics for $q$-difference equations: ${}_2\phi_0$ and $q{\rm P}_{\rm I}$
المؤلفون: Joshi, Nalini, Daalhuis, Adri Olde
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Classical Analysis and ODEs, 33D15, 34M30, 34M40, 39A13
الوصف: 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 $q$-world the $n$th coefficient is often of the size $q^{-\frac12 n(n-1)}$, in which $q\in(0,1)$ 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 ${}_2\phi_0$ and for solutions of the $q$-difference first Painlev\'e equation $q{\rm P}_{\rm I}$. These are optimal truncated expansions, and re-expansions in terms of new $q$-hyperterminant functions. The re-expansions do incorporate the Stokes phenomena.
Comment: 15 pages, 1 figure
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2403.02196
رقم الانضمام: edsarx.2403.02196
قاعدة البيانات: arXiv