Editing Kolmogorov–Arnold–Moser theorem (section)

==KAM theory==

The methods introduced by Kolmogorov, Arnold, and Moser have developed into a large body of results related to quasiperiodic motions, now known as '''KAM theory'''.  Notably, it has been extended to non-Hamiltonian systems (starting with Moser), to non-perturbative situations (as in the work of [[Michael Herman (mathematician)|Michael Herman]]) and to systems with fast and slow frequencies (as in the work of Mikhail B. Sevryuk).