Editing Quantum tunnelling (section)

=== Tunnelling in phase space ===
The concept of dynamical tunnelling is particularly suited to address the problem of quantum tunnelling in high dimensions (d>1). In the case of an [[integrable system]], where bounded classical trajectories are confined onto [[Torus|tori]] in [[phase space]], tunnelling can be understood as the quantum transport between semi-classical states built on two distinct but symmetric tori.<ref>{{Cite journal|last=Wilkinson|first=Michael|date=1986-09-01|title=Tunnelling between tori in phase space|url=https://dx.doi.org/10.1016%2F0167-2789%2886%2990009-6|journal=Physica D: Nonlinear Phenomena|language=en|volume=21|issue=2|pages=341–354|doi=10.1016/0167-2789(86)90009-6|bibcode=1986PhyD...21..341W|issn=0167-2789}}</ref>