## Journal of the Mathematical Society of Japan

### Unique solvability of some nonlinear partial differential equations with Fuchsian and irregular singularities

#### Abstract

The paper considers nonlinear partial differential equations of the form $t (\partial u/\partial t) = F(t,x,u, \partial u/\partial x)$, with independent variables $(t,x) \in \mathbb{R} \times \mathbb{C}$, and where $F(t,x,u,v)$ is a function continuous in $t$ and holomorphic in the other variables. It is shown that the equation has a unique solution in a sectorial domain centered at the origin under the condition that $F(0,x,0,0)=0$, Re$F_u(0,0,0,0)$ < 0, and $F_v(0,x,0,0)=x^{p+1}\gamma(x)$, where $\gamma(0) \neq 0$ and $p$ is any positive integer. In this case, the equation has a Fuchsian singularity at $t=0$ and an irregular singularity at $x=0$.

#### Article information

Source
J. Math. Soc. Japan, Volume 66, Number 3 (2014), 1017-1042.

Dates
First available in Project Euclid: 24 July 2014

https://projecteuclid.org/euclid.jmsj/1406206982

Digital Object Identifier
doi:10.2969/jmsj/06631017

Mathematical Reviews number (MathSciNet)
MR3238327

Zentralblatt MATH identifier
1302.35010

#### Citation

BACANI, Dennis B.; TAHARA, Hidetoshi. Unique solvability of some nonlinear partial differential equations with Fuchsian and irregular singularities. J. Math. Soc. Japan 66 (2014), no. 3, 1017--1042. doi:10.2969/jmsj/06631017. https://projecteuclid.org/euclid.jmsj/1406206982

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