Given a finite measurable partition of an interval, the itinerary of records which partition element contains each iterate . Prescribing a finite initial word defines an itinerary cylinder. For the full tent map, every length- binary cylinder has Lebesgue measure up to endpoint conventions, so its itinerary process is a fair i.i.d. Bernoulli process.
Yes. Let be -invariant. Since the itinerary variables generate modulo null sets, can be regarded as an event in the canonical sequence model. For every , invariance and imply
Thus belongs to the tail sigma-algebra of the i.i.d. sequence . By the Kolmogorov zero-one law, is zero or one. Hence the tent map is an ergodic measure-preserving transformation.
For a Borel set , the two inverse branches of the tent map are and . Apart from their immaterial common endpoint,
Each branch scales Lebesgue measure by , and their images lie in opposite half-intervals. Hence
Also , so is an invariant probability measure.
For , all orbits converge to one fixed point, and for every orbit is eventually fixed or period two, so no iterate has a horseshoe. For the symmetric tent map with slope magnitude , the topological entropy is . The interval-map positive-entropy horseshoe theorem says that a continuous interval map has positive topological entropy exactly when some iterate has a horseshoe. Hence
For this already follows from part (iii); for , a higher iterate supplies the horseshoe.