[ecma]

The Lagrangian answer covers this a bit more obviously by stating a solution which results in a closed curve of states around some equilibrium point(s) for certain initial variables. I think that matches your understanding of this as two peaks in a closed circuit.

[mirimir]

Thank you.

When I saw this thread, I was sure that it would be something about orbital mechanics or the Coriolis effect. But no, it seems.