From e0e816946ce932d9e25af39b89c6920b8f148ebf Mon Sep 17 00:00:00 2001 From: Scarlett Gauthier <s.s.gauthier@student.tudelft.nl> Date: Wed, 19 Aug 2020 10:16:02 +0000 Subject: [PATCH] Add up to figure on page 6 --- src/differential_equations_2.md | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/differential_equations_2.md b/src/differential_equations_2.md index ca9401f..4081c79 100644 --- a/src/differential_equations_2.md +++ b/src/differential_equations_2.md @@ -334,6 +334,22 @@ To summarize, this process has broken one partial differential equation into two ordinary differential equations of different variables. In order to do this, we needed to introduce a separation constant, which remains to be determined. +### Boundary and eigenvalue problems ### + +Continuing on with the Schr\"{o}dinger equation example from the previous +section, let us focus on + +$$-\frac{\hbar^2}{2m} \phi''(x) = \lambda \phi(x),$$ +$$\phi(0)=\phi(L)=0.$$ + +This has the form of an eigenvalue equation, in which $\lambda$ is the +eigenvalue, $- \frac{\hbar^2}{2m} \frac{d^2}{dx^2}[\cdot]$ is the linear +operator and $\phi(x)$ is the eigenfunction. + +Notice that when stating the ordinary differential equation, it is specified +along with it's boundary conditions. Note that in contrast to an initial value +problem, a boundary value problem does not always have a solution. + -- GitLab