Abstract
Concurrence is an entanglement measure characterizing the mixed state bipartite correlations inside of a pure state of an -qubit system. We show that after organizing the charges and the moduli in the STU model of , supergravity to a three-qubit state, for static extremal spherically symmetric Bogomolny-Prasad-Sommerfield (BPS) black-hole solutions the vanishing condition for all of the bipartite concurrences on the horizon is equivalent to the attractor equations. As a result of this, the macroscopic black hole entropy given by the three-tangle can be reinterpreted as a linear entropy characterizing the pure state entanglement for an arbitrary bipartite split. Both for the BPS and non-BPS cases, explicit expressions for the concurrences are obtained, with their vanishing on the horizon is demonstrated.
- Received 29 November 2010
DOI:https://doi.org/10.1103/PhysRevD.83.045005
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