"In the years before 1920, the picture of space as a three-dimensional
space, and of time as a separate thing, was changed by Einstein,
first into a combination which we call space-time, and then still
further into a curved space-time to reflect gravitation. Then
it was also found that the rules for the motion of particles were
incorrect. The mechanical rules of inertia and forces
are wrong--Newton's laws are wrong--in the world of atoms.
Instead it was found that things on a small scale behave nothing like
things on a large scale. "
Richard Feynman
The Feynman Lectures on Physics
For all the suspension of disbelief that quantum mechanics requires,
students approaching this subject should at all times remember that
quantum mechanics is possibly sciences greatest achievement in empirical
science. The foundations of quantum mechanics are not in theory, but
in facts that are observable and repeatable. All particles interact in
a way that as of yet we can only describe as wave interaction. The
interaction of light with matter occurs in a manner that as of yet we
can only describe with discrete energy levels. The quantization of
energy levels in hydrogen is observed clearly in hydrogen spectra,
and can be seen by as simple a process as exciting hydrogen gas in a
glass tube by running current through either end, and observing the
light produced through a refraction grating.
The hydrogen atom allows us to address our understanding of
quantum mechanics at all levels: empirical through the observed spectra
of hydrogen gas, theoretical through one of the rare cases in which
Schrodinger's equation can be solved exactly, and computational by
methods which will be the building blocks of our understanding of
large molecules. A numerical solution can be verified by comparing
to the theoretical solution, and can be validated by comparing to
empirical data.
This module will begin with a discussion of the observations that
led to quantum theory, through introductory exercises to practice
skills required in the solution of the hydrogen atom, and culminating
in solving for and visualizing the orbitals of the lowest energy
states of a single electron hydrogen atom.