Quantized time in quantum walks under weak rank-K measurements

Klaus Ziegler

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arXiv · 2606.13552

Quantized time in quantum walks under weak rank-K measurements

Klaus Ziegler

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Abstract

Measurements can be used to monitor the evolution of quantum systems and may lead to a universally quantized time statistics. It is known that the mean return time is quantized for strong and indirect monitoring through the winding number of the return amplitude in a one-dimensional space. Here we discuss that under multi-channel strong or indirect monitoring, where the latter is achieved through ancilla coupling, the mean return time of a quantum walk in the projected subspace is also quantized. This reflects a universal time quantization for a higher dimensional evolution.

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Klaus Ziegler. 2026-06-11. Quantized time in quantum walks under weak rank-K measurements. https://arxiv.org/abs/2606.13552

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