I'm interested to know if anyone can give me some information (name, references, etc.) about this PDE $$\nabla \omega^2= \alpha \omega^n+ \beta,$$ where $\omega$ is a scalar function of two or more variables, $\alpha$ and $\beta$ are arbitrary constants $\in$ $\mathbb{R}$.
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$\begingroup$ I do not understand it. From the equation you get that $\omega=(\beta/\alpha)^{1/n}$ is constant. There must be a mistake in your statement. $\endgroup$ – Piotr Hajlasz Nov 30 '18 at 13:31

$\begingroup$ @Piotr Hajlasz  Yes, there was a mistake, thank you! $\endgroup$ – Alexander Pigazzini Nov 30 '18 at 13:47

$\begingroup$ It looks like an eikonal equation with a nonlinear wave speed; that's what I would search for anyway as a start. $\endgroup$ – Willie Wong Nov 30 '18 at 14:33

$\begingroup$ @Willie Wong  Thank you very much! $\endgroup$ – Alexander Pigazzini Nov 30 '18 at 14:36

1$\begingroup$ Actually, can you not transform this into a standard eikonal equation? If you let $F:\mathbb{R}\to\mathbb{R}$ be a primitive of $(\alpha z^n + \beta)^{\frac12}$, then your equation is equivalent to $\nabla F(\omega) = 1$ which is the standard eikonal equation. $\endgroup$ – Willie Wong Nov 30 '18 at 14:42