(ξαn)n≥1 is not uniformly distributed modulo one for Pisot α and ξ in the Cantor set C(α)
Bugeaud's Problem 10.61, due to Michel Mendès France in 1967: for a Pisot number α>2 and the Cantor set C(α)={(α−1)∑k≥1εkα−k:εk∈{0,1}}, no ξ∈C(α) has (ξαn)n≥1 uniformly distributed modulo one.
The problem itself remains open. What is proved is a set of criteria for it, and two instances. The criteria: a reduction to symbolic dynamics that is an equivalence; a pressure criterion; and a covering criterion which, for a quadratic setup of norm b, applies exactly when (log2α−1)(log2(α/∣b∣)−1)>1, a condition that reduces to α>4 for units. The two instances are both quadratic: at α=2+5 in the strong form, an explicit interval that every orbit misses at every time, and at α=2+3 by a confinement-gap certificate.
The problem is open, and the repository says so: what is proved are criteria for it and two instances, not the general case.
Every compared statement that concludes Problem 10.61 does so for a quadratic setup - a real root α>1 of X2−aX−b whose conjugate has modulus below one - and both instances are quadratic. The arbitrary-degree material is conditional ingredients: for the family…
Bugeaud's Problem 10.61, due to Michel Mendès France in 1967: for a Pisot number α>2 and the Cantor set C(α)={(α−1)∑k≥1εkα−k:εk∈{0,1}}, no ξ∈C(α) has (ξαn)n≥1 uniformly distributed modulo one.
The problem itself remains open. What is proved is a set of criteria for it, and two instances. The criteria: a reduction to symbolic dynamics that is an equivalence; a pressure criterion; and a covering criterion which, for a quadratic setup of norm b, applies exactly when (log2α−1)(log2(α/∣b∣)−1)>1, a condition that reduces to α>4 for units. The two instances are both quadratic: at α=2+5 in the strong form, an explicit interval that every orbit misses at every time, and at α=2+3 by a confinement-gap certificate.
The problem is open, and the repository says so: what is proved are criteria for it and two instances, not the general case.
Every compared statement that concludes Problem 10.61 does so for a quadratic setup - a real root α>1 of X2−aX−b whose conjugate has modulus below one - and both instances are quadratic. The arbitrary-degree material is conditional ingredients: for the family Xd−aXd−1−1 the real root exceeding a is shown to be Pisot for a≥3, with a conjugate-modulus bound and a numerical inequality. No compared statement carries those above degree two, because the covering criterion is proved only for quadratic setups.
The covering criterion also leaves quadratic α with route-A exponent at least one undecided, about which nothing is claimed.
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Bugeaud's Problem 10.61, due to Michel Mendès France in 1967: for a Pisot number α>2 and the Cantor set C(α)={(α−1)∑k≥1εkα−k:εk∈{0,1}}, no…