Joint Quantum Entropy

The joint quantum entropy generalizes the classical joint entropy to the context of quantum information theory. Intuitively, given two quantum states and, represented as density operators that are subparts of a quantum system, the joint quantum entropy is a measure of the total uncertainty or entropy of the joint system. It is written or, depending on the notation being used for the von Neumann entropy. Like other entropies, the joint quantum entropy is measured in bits, i.e. the logarithm is taken in base 2.

In this article, we will use for the joint quantum entropy.

Read more about Joint Quantum Entropy:  Background, Definition, Properties, Relations To Other Entropy Measures

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