Laplace-Runge-Lenz vector and its generating transformation

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SUMMARY

The discussion centers on the Laplace-Runge-Lenz (LRL) vector and its relationship to symmetries in central potentials. The LRL vector is identified as a conserved quantity derived from Noether's theorem, specifically through infinitesimal Lorentz transformations and canonical transformations. The conversation highlights the connection between kinematical symmetries and dynamical quantities, emphasizing the need for a deeper understanding of conserved quantities and their derivation. The participant expresses frustration over the complexity of existing resources and seeks clearer explanations of the LRL vector's formulation and its implications.

PREREQUISITES
  • Understanding of Noether's theorem
  • Familiarity with canonical transformations
  • Knowledge of kinematical and dynamical symmetries
  • Basic concepts of central potentials in classical mechanics
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  • Research the derivation of the Laplace-Runge-Lenz vector in classical mechanics
  • Explore advanced applications of Noether's theorem in various physical systems
  • Study the implications of kinematical symmetries in quantum mechanics
  • Investigate other conserved quantities arising from dynamical symmetries
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Physicists, researchers in classical mechanics, and students studying symmetries and conserved quantities in dynamical systems.

Sonty
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I have this sort of research project about symmetries under the central potential and I'm stuck on this Runge-Lenz vector. As it is a conserved quantity I was expecting it to come out of Noether's theorem. I can't figure out how. So I go on the net to find out and get 2 answers: infinitesimal Lorentz trasnformation without rotation followed by a time translation and a more explicit article on a canonical transformation. Out of the latter I find that besides the usual space-time transformations come the so called kinematical symmetries, while out of symmetries in the phase space comes another kind of conserved quantities called dynamical. It shows rather clearly that the angle the LRL vector makes with the x-axis is the canonical conjugate of L and that's the pair of variables I should canonical transform to.
What other dynamical symmetries are there in the world that I heven't heared of and how should the conserved quantities look in general terms? Is there an analogue to Noether's theorem that would tell me exactly how the conserved quantity should look like? How did Laplace, Runge and Lenz get the expression for the vector?
 
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that's the first result in google's search and the second in teoma's. It doesn't help. It's like trees are green, the sky is blue, the water is wet, stuff like that. It doesn't say why or how.
 
I had it but didn't fully read it. I had just skimmed through it searching for keywords. Didn't find them until I actually read a big part of it. In my reaction I confused it for another one. The thing is that seems to me to elaborate. I don't think that's what I'm supposed to get. I couldn't follow his calculations fully, maybe because I'm tired and I've been fighting this nasty flu for a couple of days. There's got to be an easier way to do it.
 

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