Exact Perturbative Existence and Uniqueness Theorem

Autor:	Nikolaev, Nikita
Rok vydání:	2022
Předmět:	Mathematics - Classical Analysis and ODEs Mathematical Physics Mathematics - Analysis of PDEs 34M6 (primary) 34M04 34M30 34E15 34E20 34A12 34A34
Druh dokumentu:	Working Paper
Popis:	We prove a general existence and uniqueness theorem for holomorphic perturbative solutions of singularly perturbed nonlinear complex differential systems of the form $\hbar \partial_x f = F (x, \hbar, f)$ where $\hbar$ is a small complex perturbation parameter. Specifically, we give conditions that allow us to promote, in a unique and precise sense, a formal perturbative solution $\hat{f} (x, \hbar)$ to a holomorphic solution $f (x, \hbar)$ whose perturbative expansion is $\hat{f}$. Furthermore, we prove that $f$ is the uniform Borel resummation of $\hat{f}$. As sample applications, we analyse the Painlev\'e I equation as well as derive exact WKB solutions for a generalised 3\textsuperscript{rd}-order Airy equation. Comment: Comments are welcome!
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2201.04526 Zobrazit plný text záznamu View this record from Arxiv