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

Fermat's principle Integral

  1. Jul 24, 2014 #1
    I am unable understand this Integral, what does it actually saying? What does that "δ" means here? I haven't learnt Calculus of variations, explain me with diagrams with possible.
     

    Attached Files:

  2. jcsd
  3. Jul 24, 2014 #2

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    It pretty much says what it means. The integral [itex]\int_{A\to B} n ds[/itex] is the integral of n along some path from point A to point B. The "[itex]\delta[/itex]" in front means that we are considering what happens when we vary that path "infinitesimally".
     
  4. Jul 26, 2014 #3
    The point that may be giving you trouble is that the integral is taken along the path, while the variation expressed by the delta is varying the path itself. Think of a path from A to B wiggling slightly: the wiggle is the delta.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Fermat's principle Integral
Loading...