A holographic proof of the strong subadditivity of entanglement entropy
نویسندگان
چکیده
When a quantum system is divided into subsystems, their entanglement entropies are subject to an inequality known as strong subadditivity. For a field theory this inequality can be stated as follows: given any two regions of space A and B, S(A)+S(B) ≥ S(A∪B)+ S(A ∩ B). Recently, a method has been found for computing entanglement entropies in any field theory for which there is a holographically dual gravity theory. In this note we give a simple geometrical proof of strong subadditivity employing this holographic prescription.
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