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What is the physical meaning of curvature?

  1. Oct 17, 2011 #1
    I'm not sure if this belongs here or in the physics section. The mathematical definition of curvature is the derivative of the unit tangent vector normalized to the arc length: [itex]\kappa[/itex] = [itex]\frac{dT}{ds}[/itex]. If we apply this to a parabola with equation y = [itex]x^{2}[/itex] we get [itex]\frac{2}{(1+4x^{2})^{3/2}}[/itex]. This resembles a lorenzian line shape which is the distribution function (amplitude vs frequency) of a harmonic oscillator in a parabolic potential (i.e. a graph of amplitude vs frequency shows a resonance at some frequency.)

    My question:

    Is the curvature of a potential energy function related to the distribution function of the potential energy function or does it have some other physical relationship that I am missing? Or is the resemblance of the curvature of a parabola and the lorenzian line shape a coincidence?

    Sorry if this is kind of vague let me know if you have questions.
    Last edited: Oct 17, 2011
  2. jcsd
  3. Oct 18, 2011 #2
    The curvature of potential energy is definitely related to distribution function, but the dependence is weird.I can't give any physical meaning to curvature which might suit the dependence.
  4. Oct 18, 2011 #3
    The curvature of a surface is (or at least can be) defined as moving a vector through parallel transport around a closed loop.
  5. Oct 18, 2011 #4
    Thanks for the responses. I'm not familiar with parallel transport so I'll study up and see if it can answer my question.
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