| MadSci Network: Physics |
I’m not sure where to begin because I don’t know how much you already
know about quantum mechanics, so I’ll take the safe way out and start at
the beginning. Quantum mechanics started at the beginning of the 1900s
when physicists noticed matter had certain properties that classical
physics (also known as Newtonian Physics) couldn’t explain – or at least
couldn’t explain properly.
Basically, classical physics says that for any object, all energy
levels are possible. That is, an object can have any arbitrary amount of
energy. But when physicists started to experiment with atomic spectra,
they noticed that the spectra were not continuous as classical physics
predicted but rather the spectra seemed to be discontinuous, and only
certain wavelengths were possible. Max Plank (using blackbody radiation)
was one of the first to notice this and propose an explanation. According
to Plank, energy could only exist in small packets, which he called quanta
(hence the name quantum mechanics).
Further experiments showed that matter had wavelike properties. On
the macroscopic scale, we cannot notice these properties, but on the
microscopic scale, such as the scale of an atom, properties like
wavelength and frequency are quite noticeable. So now that we know matter
has wavelike character, we have to find a way to incorporate that into our
theory of the atom. In the 1920s an Austrian Physicist named Erwin
Scrodinger came up with the “Schrodinger Equation” and something he called
the “wavefunction.” According to these ideas, one cannot know exactly
where a particle is, but we can speak of its location in terms of
probability by using its wavefunction.
Like Newton’s Laws of Motion, the Schrodinger Equation cannot be
derived, but if one studies it closely, the equation can be used to derive
other known and accepted relations such as the de Broglie equation, which
relates an object’s momentum to it’s wavelength.
Some other physicists who have contributed to quantum mechanics
include Albert Einstein, Max Born, and Heisenberg (I’m not sure what his
first name is). Heisenberg probably demonstrated one of the most
interesting ideas put forth by quantum mechanics. According to the
Heisenberg Uncertainty Principle, one cannot know an object’s momentum and
location with arbitrary precision. That is, if you know exactly how fast
something is moving (you can use velocity to find momentum) then you
cannot know exactly where that object is.
As for what to study while in college: You can either study physics
or chemistry as an undergraduate. In both majors you will get a taste of
quantum mechanics. Chemists usually deal with lower energy measurements
and calculations since they are only interested in the relatively low
energies involved in chemical reactions and to excite electrons in.
Physicists are usually involved in the high-energy end of the spectrum
when it comes to studying quantum mechanics. If you major in chemistry
you will probably get a small taste of quantum mechanics during your
freshman year. More advanced quantum mechanics is usually taught in
junior or senior level physical chemistry course. I’m not sure how it
works out in if you were to major in physics; I’m sure depending on school
it will vary.
I’m not sure what the leading schools are for studies in quantum
mechanics. What’s really important is to go to a school that you like.
Also remember that as an undergraduate you’ll study a wide variety of
topics in your field, not just quantum mechanics. As a graduate student,
you will usually focus attention on one topic (such as quantum mechanics).
If you want to teach yourself some quantum mechanics basics any
introductory text will probably do the trick. Quantum mechanics also
involves quite a bit of calculus, so a good math background will help
quite a bit. In fact, in order to understand a lot of quantum mechanical
proofs and concepts, you will need to know how to differentiate and
integrate equations as well as some basic formulas (some important
formulas include Euler’s Formula and de Moivre’s Formula).
Hope this helps! Good luck with reaching your goal!
Try the links in the MadSci Library for more information on Physics.