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arXiv:2512.24950

An uncertainty relation in the case of four observables

Minyi Huang

quant-phSubmitted Dec 31, 2025• Announced Jan 1, 2026• 0 citations• Revised Jan 28, 2026 (v2)
v1 · Dec 31, 2025v2 · Jan 28, 2026
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Abstract

Uncertainty is a fundamental and important concept in quantum mechanics. In this work, using the technique in matrix theory, we propose an uncertainty relation of four observables and show that the uncertainty constant is tight. It is argued that this method can deal with the several known uncertainty relations for two, three and four observables in a unified way. The result is also compared with other uncertainty relations of four observables.

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5 pages

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