Inhomogeneous multiplicative Khintchine-type conjecture

About 8 years old · traced to

Let α1,…,αk−1∈R\alpha_1,\ldots,\alpha_{k-1}\in\mathbb R. For n∈Zn\in\mathbb Z, define n+=max⁡(∣n∣,2)n^+=\max(|n|,2) and

ψ:Z⩾2→R⩾0,ψ(n)=n−1(log⁡n)−k.\psi:\mathbb Z_{\geqslant 2}\to\mathbb R_{\geqslant 0},\qquad \psi(n)=n^{-1}(\log n)^{-k}.

Inhomogeneous multiplicative Khintchine-type conjecture. Then for almost all αk∈R\alpha_k\in\mathbb R, there exist infinitely many (n1,…,nk)∈Zk(n_1,\ldots,n_k)\in\mathbb Z^k such that

∣n1α1+⋯+nkαk∣<ψ(n1+⋯nk+).\\|n_1\alpha_1+\cdots+n_k\alpha_k\\|<\psi(n_1^+\cdots n_k^+).

This is posed in the paper’s discussion of the dual problem and is therefore open in the supplied source.

References

Primary source

Sam Chow and Niclas Technau, “Higher-rank Bohr sets and multiplicative diophantine approximation”, arXiv:1810.04558 (2018).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.