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arXiv · 1507.07119

Badly approximable points in twisted Diophantine approximation and Hausdorff dimension

Paloma Bengoechea·Nikolay Moshchevitin
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Abstract

For any j_1,...,j_n>0 with j_1+...+j_n=1 and any x \in R^n, we consider the set of points y \in R^n for which max_{1\leq i\leq n}(||qx_i-y_i||^{1/j_i})>c/q for some positive constant c=c(y) and all q\in N. These sets are the `twisted' inhomogeneous analogue of Bad(j_1,...,j_n) in the theory of simultaneous Diophantine approximation. It has been shown that they have full Hausdorff dimension in the non-weighted setting, i.e provided that j_i=1/n, and in the weighted setting when x is chosen from Bad(j_1,...,j_n). We generalise these results proving the full Hausdorff dimension in the weighted setting without any condition on x.

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Paloma Bengoechea, Nikolay Moshchevitin. 2015-07-25. Badly approximable points in twisted Diophantine approximation and Hausdorff dimension. https://arxiv.org/abs/1507.07119

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