Negativity (quantum mechanics)

Negativity in quantum mechanics is a concept related to the characterization of quantum states, specifically in the context of quantum entanglement and the dynamics of quantum systems. The term usually refers to a measure of quantum correlations in mixed states, particularly when discussing the separability of quantum states. In quantum information theory, the negativity quantifies the degree to which a quantum state deviates from being separable (i.e., expressible as a mixture of product states).