Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why is the concept of a one dimensional box used?

  1. Apr 10, 2013 #1
    I'm not sure I know all that I should to understand it. I'm posting to try and determine if I do.

    Knowing what I know, however, it seems unnecessarily confusing. Almost all students I talk to agree.

    Why not just call it a particle on a line segment? Or just moving in one dimension?
  2. jcsd
  3. Apr 10, 2013 #2
    you assume that the walls are infinite in two other dimensions. it is not a one dimensional problem per se: two other dimensions decouple and their solutions are just plane waves, the interesting part is in the dimension where walls stand.

    Quantum mechanics of one dimension is very different.
  4. Apr 10, 2013 #3
    I've seldom heard it referred to as a "one-dimensional box." Usually it's called the infinite square well. It may not be the most realistic potential, but it's easy to solve and gives you some intuition about how quantum mechanics works (you can see the discrete energy levels, you can do simple calculations with the position and momentum operators, etc.). For a two- or three-dimensional infinite square well, you can start to discuss degeneracy too, which is essential later on. I think it's basically just a simple model that illustrates a lot of important concepts.
  5. Apr 10, 2013 #4
    it also has some relevance for chemistry, for polyenes.
  6. Apr 10, 2013 #5
    you have to start with something...

    its like why you start classic physics with F=const in one dimension
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook