The Quantum Uncertainty Page

Here are links that lead you to Wolfram demonstrations illustrating measurement uncertainty relations and joint measurability conditions for qubit observables.

 

The first demo illustrates a simple inequality and its proof in such a way that you can get a feel for the interplay between (a) the degree of the incompatibility of two sharp qubit observables that one wishes to measure jointly albeit approximately, (b) the approximation errors for both observables, and (c) the degrees of intrinsic unsharpness that one must allow for the approximate measurements to be compatible, that is, jointly applicable.

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The second demo is an exploration of all possible joint measurements for a choice of a pair of incompatible qubit observables; it allows you to explore the realisation of the optimal boundary curve for the admissible region of error pairs.

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The third demo explains a theorem that sets out necessary and sufficient conditions for a pair of qubit observables to be jointly measurable, or coexistent, or compatible (all three terms being used synonymously in different parts of the literature).