##

The Time Independent Schrödinger Equation

Second order differential equations, like the Schrödinger Equation,
can be solved by **separation of variables**.
These separated solutions can then be used to solve the problem in general.

Assume that we can **factorize** the solution between time and space.

Plug this into the Schrödinger Equation.

Put everything that depends on
on the left and everything that depends on
on the right.

Since we have a function of only
set equal to a function of only
,
they **both must equal a constant**.
In the equation above, we call the constant
, (with some knowledge of the outcome).
We now have an equation in
set equal to a constant

which has a simple **general solution**,

and an equation in
set equal to a constant

which depends on the problem to be solved (through
).
The
equation is often called the **Time Independent Schrödinger Equation**.

Here,
is a constant.
The **full time dependent solution** is.
* Example:
Solve the Schrödinger equation for a constant potential .*

Jim Branson
2013-04-22