Stronger uncertainty relations with improvable upper and lower bounds

  title={Stronger uncertainty relations with improvable upper and lower bounds},
  author={Jiandi Zhang and Yang Zhang and Chang-shui Yu},
  journal={Quantum Information Processing},
The quantum superposition principle is used to establish improved upper and lower bounds for the Maccone–Pati uncertainty inequality, which is based on a “weighted-like” sum of the variances of observables. Our bounds include free parameters that not only guarantee nontrivial bounds but also effectively control the bounds’ tightness. Significantly, these free parameters depend on neither the state nor the observables. A feature of our method is that any nontrivial bound can always be improved… Expand
6 Citations
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