Understanding the (restricted) three body problem

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The discussion focuses on the complexities of the restricted three-body problem, emphasizing that it has nine degrees of freedom but only four independent first integrals, making it non-integrable. It highlights that the Lagrangian in an inertial frame is time-dependent due to the constant rotation of two massive bodies, leading to non-conservation of energy. Transitioning to a synodic frame eliminates this time dependence, allowing for conservation of certain quantities, although the Hamiltonian does not represent total mechanical energy due to inertial forces. The total energy is not conserved in the synodic frame, while the Lagrangian points are identified as the only equilibrium points in this context. The user expresses interest in further exploring the topic and shares their primary resource, "Celestial Dynamics" by Dvorak and Lhotka.
throneoo
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Hello. Recently I've been trying to understand this problem but I'm not sure if I'm doing it correctly. So I'd like to show you some statements formed from my understanding on the subject and you guys could correct me if I'm wrong.

General:
1)The problem has 3*3=9 degrees of freedom and n independent first integrals is needed to solve it using quadrature (Integrable).

2)The independent first integrals here is the center of mass/ total momentum/ total angular momentum (3) and total energy (1) =4 which is not enough to be qualified as integrable.

Circularly restricted (3D)
3) In the inertial frame, the lagrangian is explicitly time dependent as the distances from the two massive bodies depend explicitly on time (constant rotation), hence both the lagrangian and hamiltonian are not conserved.

4)Transforming to the synodic (rotating) frame removes the explicit time dependence so those quantities are conserved, but the hamiltonian is not the total mechanical energy (due to the centrifugal and coriolis force)

5)Total energy is not conserved in the synodic frame due to the inertial forces. Presumably it is conserved in the inertial frame despite the fact that the gravitational influence from the smallest body is neglected.

6) The Lagrangian points are the only equilibrium points in the synodic frame.

Thanks for your help! I might add more to the thread.
 
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This is an interesting problem for me, too. What books are you using?
 
dextercioby said:
This is an interesting problem for me, too. What books are you using?
Celestial Dynamics by Dvorak and Lhotka is the main text. I also read a lot of articles on this subject
 
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