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arXiv · 2308.05690

A Universal Quantum Certainty Relation for Arbitrary Number of Observables

Ao-Xiang Liu·Ma-Cheng Yang·Cong-Feng Qiao
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Abstract

We derive by lattice theory a universal quantum certainty relation for arbitrary $M$ observables in $N$-dimensional system, which provides a state-independent maximum lower bound on the direct-sum of the probability vectors in terms of majorization relation. While the utmost lower bound coincides with $(1/N,...,1/N)$ for any two observables with orthogonal bases, the majorization certainty relation for $M\geqslant3$ is shown to be nontrivial. The universal majorization bounds for three mutually complementary observables and a more general set of observables in dimension-2 are achieved. It is found that one cannot prepare a quantum state with probability vectors of incompatible observables spreading out arbitrarily. Moreover, we also explore the connections between quantum uncertainty and quantum coherence, and obtain a complementary relation for the quantum coherence as well, which characterizes a trade-off relation of quantum coherence with different bases and is illustrated by an explicit example.

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Ao-Xiang Liu, Ma-Cheng Yang, Cong-Feng Qiao. 2025-08-22. A Universal Quantum Certainty Relation for Arbitrary Number of Observables. https://doi.org/10.1007/s11128-025-04901-8

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