Cotangent bundle: vector bundle T*(T*M) over T*M.

TM & TM* bundle = manifold, with twice the dimension of M

R-metric, symplectic -> TM ~ TM* (isomorphic)

trivial: TM is M * R^n form.

Cotangent bundle and HMC

cotangent bundle = phase space on which Hamiltonian mechanics plays out.

tangent bundle