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Register a new userNew computable entanglement monotones from formal group theory
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Piergiulio Tempesta
Publication date
2019
fields
Physics
and research's language is
English
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We present a mathematical construction of new quantum information measures that generalize the notion of logarithmic negativity. Our approach is based on formal group theory. We shall prove that this family of generalized negativity functions, due their algebraic properties, is suitable for studying entanglement in many-body systems. Under mild hypotheses, the new measures are computable entanglement monotones. Also, they are composable: their evaluation over tensor products can be entirely computed in terms of the evaluations over each factor, by means of a specific group law. In principle, they might be useful to study separability and (in a future perspective) criticality of mixed states, complementing the role of Renyis entanglement entropy in the discrimination of conformal sectors for pure states.
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