Laplace-Runge-Lenz vector and its generating transformation

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The discussion revolves around the challenges faced in understanding the Runge-Lenz vector and its relation to symmetries under central potentials. The individual is seeking clarity on how this conserved quantity arises from Noether's theorem and is exploring various resources that provide differing explanations, including Lorentz transformations and canonical transformations. They express frustration over the complexity of existing explanations and the lack of straightforward answers regarding dynamical symmetries and conserved quantities. Additionally, there is a desire for a clearer understanding of how historical figures like Laplace, Runge, and Lenz derived the vector's expression. The conversation highlights a need for more accessible resources or simplified explanations to grasp these advanced concepts.
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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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