1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Conservation of the Laplace-Runge-Lenz Vector

  1. Oct 21, 2008 #1
    Hmm...Latex doesn't seem to be working at the moment...

    How does one show the conservation of the Laplace-Runge-Lenz (LRL) vector using the Hamiltonian of the two-body system? Showing it's conserved otherwise it's not hard. You can take the time derivative of the LRL vector and show that it's zero or a couple other ways which I worked out before (I would type it out but Latex seemingly disabled makes it tedious and cumbersome). The one thing I can't figure out is how to get the conservation of the LRL vector from the Hamiltonian of the two-body system. What I did was take the square of the LRL vector and find the energy from that but then it becomes uncertain.
  2. jcsd
  3. Oct 21, 2008 #2
    You know how to calculate commutators?
  4. Oct 23, 2008 #3
    Ah yes yes, thank you, I got it now.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook