- #1
Peeter
- 303
- 3
My quantum text, leading up to the connection formulas for WKB and the Bohr-Sommerfeld quantization condition states that for
\begin{align}u'' + c x^n u = 0 \end{align}
one finds that one solution is
\begin{align}u &= A \sqrt{\eta k} J_{\pm m}(\eta) \\ m &= \frac{1}{{n + 2}} \\ k^2 &= c x^n \\ \eta &= \int_0^x dx' k(x')\end{align}
I'd like to know how this was arrived at. Could somebody outline what set of change of variables would one make to put the differential equation above into the standard Bessel differential form?
\begin{align}u'' + c x^n u = 0 \end{align}
one finds that one solution is
\begin{align}u &= A \sqrt{\eta k} J_{\pm m}(\eta) \\ m &= \frac{1}{{n + 2}} \\ k^2 &= c x^n \\ \eta &= \int_0^x dx' k(x')\end{align}
I'd like to know how this was arrived at. Could somebody outline what set of change of variables would one make to put the differential equation above into the standard Bessel differential form?