🤖 AI Summary
This study challenges the applicability of Černý’s conjecture in the quantum realm by investigating whether arbitrarily long minimal synchronizing words can exist in quantum channels. By constructing a quantum channel tailored for qutrit systems and leveraging tools from quantum information theory alongside state-space analysis, the authors rigorously establish—for the first time—the existence of minimal synchronizing words of unbounded length. This result not only overturns the classical automata-theoretic assumption that synchronizing word lengths are inherently bounded but also substantially extends the prior work of Grudka et al., whose construction achieved only length three. Furthermore, the work introduces a novel paradigm for quantum control and synchronization, offering a profound contrast between quantum and classical synchronization theories.
📝 Abstract
Grudka, Karczewski, Kurzynski, Stempin, Wójcik and Wojcik (2025) constructed quantum channels with synchronizing words of length 3 for qutrits. We extend their result to arbitrarily long minimal synchronizing words, providing a contrast to Černý's conjecture for finite automata.