- #1
andresB
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- TL;DR Summary
- Does the Hamilton-Jacobi equation exist for chaotic systems?
Given a Hamiltonian ##H(\mathbf{q},\mathbf{p})##, in the time-independent Hamilton-Jacobi approach we look for a canonical transformation ##(\mathbf{q},\mathbf{p})\rightarrow(\mathbf{Q},\mathbf{P})## such that the new Hamiltonian is one of the new momenta $$H(\mathbf{q},\mathbf{p})=K(\mathbf{Q},\mathbf{P})=P_{1}=E.$$
If such transformation exists, all the momenta ##\mathbf{P}## are constant of the motion. And, since the transformation is canonical, we will have n constant of the motion in involution, i.e., ##\left\{ P_{i},P_{j}\right\} =0.## But this seems to be the requirement of the Liouville theorem for integrability. Chaotic systems don't have that many constants of motion in involution.
This seems to imply that the Hamilton-Jacobi equations cannot be even written for chaotic systems, so my reasoning has to be wrong somewhere. Where?
If such transformation exists, all the momenta ##\mathbf{P}## are constant of the motion. And, since the transformation is canonical, we will have n constant of the motion in involution, i.e., ##\left\{ P_{i},P_{j}\right\} =0.## But this seems to be the requirement of the Liouville theorem for integrability. Chaotic systems don't have that many constants of motion in involution.
This seems to imply that the Hamilton-Jacobi equations cannot be even written for chaotic systems, so my reasoning has to be wrong somewhere. Where?
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