4 problems

Quantitative $R_\epsilon$-conjecture. There is a natural number $r=r(\epsilon,A,B)$ such that, for every $n\in\mathbb N$ and every such sequence, there is a partition…

$R_\epsilon$-conjecture. Every unit norm Riesz basic sequence is a finite union of $\epsilon$-Riesz basic sequences.

Finite-union conjecture. Every bounded below ASF can be partitioned as a finite union of ARSs. The source's statement uses “ARBs,” but the preceding definition introduces ARSs; thi…

Feichtinger conjecture. The sequence $\{\tau_n\}_n$ can be partitioned into a finite union of Riesz sequences for $\mathcal{H}$. This conjecture was proved by Marcus, Spielman and…