“…This question has been studied in depth in the lowest dimensional case, in which the question is nontrivial, i.e. for a hypersurface Σ ⊂ R 4 in [8,12,13,17,18,19,21]. It turns out that, in this case, (Σ, α) carries at least two simple periodic orbits and if there are more than two simple periodic orbits, infinitely many of them are guaranteed generically.…”