What is Quantum Mechanics and how is it related to time travel?
Quantum mechanics replaces Hamiltonian mechanics when the action becomes comparable to Planck's constant.
Quantum Mechanics is just a upgraded version of Hamiltonian Mechanics. But they both work on very different scales.
Hamiltonian Mechanics works on large scale and up-to some sort of small scale. But, quantum mechanics works on Planck's Scale. where the range is so small that we measure it in above
Up until now, the equations and theory of time travel were based on classical mechanics. But now the recent studies have started working on equations of quantum mechanics on time travel.
A rule known as
For more information, see this.