Experimental Test of Information-Theoretic Measurement Uncertainty Relation for general Qubit ObservablesDecember 15, 2018 11:41 am
Heisenberg’s uncertainty principle is without a doubt an important tenet of quantum physics. In our latest experiment we tested an uncertainty relation consisting of a sum of Shannon entropies. It is a basic property in quantum mechanics that accurate information of two incompatible or non-commuting observables has limitation – this is reflected in the uncertainty principle.
This issue, which induces => is represented by the uncertainty principle, can be made more difficult when considering not only operators given by projectors, but more generally by unsharp observables. => This issue, represented/given by the uncertainty relation, gets more complexities (?)/crucial when not only operators given by projectors, but more generally by unsharp observables are involved.
In this letter we provide experimental evidence that when using POVMs in a qubit system, as is the case for the neutron spin used in the experiment(?), the measurement uncertainty between these observables can be lower than => reduced from their sharp (projective?) counterparts. Thus => Since this provides more accurate and general evidence than our previous publication in PRL[…], the results => present manuscript/letter will be of broad interest for the entire quantum information theory community making a publication suitable for Physical Review Letters.