“…This is the basic argument that drives the proof that almost every interval exchange map with flips is non-ergodic in [6]. Namely, the fact that the map acts locally as an isometry implies that, if we take d := min k=1,...,p {dist(T k · x 0 , D)}, where p is the period of x 0 and D is the discontinuity set, then the ball B d (x 0 ) follows the orbit of x 0 at all iterations and, therefore, the Lebesgue measure supported on the union of the iterates of B d (x 0 ) is an invariant measure, hence preventing any invariant non-atomic Borel measure from being ergodic.…”