ua nt - p h / 00 09 06 3 v 1 1 4 Se p 20 00 Entanglement of Formation of an Arbitrary State of Two Rebits ∗
نویسندگان
چکیده
We consider entanglement for quantum states defined in vector spaces over the real numbers. Such real entanglement is different from entanglement in standard quantum mechanics over the complex numbers. The differences provide insight into the nature of entanglement in standard quantum theory. Wootters [Phys. Rev. Lett. 80, 2245 (1998)] has given an explicit formula for the entanglement of formation of two qubits in terms of what he calls the concurrence of the joint density operator. We give a contrasting formula for the entanglement of formation of an arbitrary state of two “rebits,” a rebit being a system whose Hilbert space is a 2-dimensional real vector space.
منابع مشابه
nt - p h / 02 03 01 1 v 1 4 M ar 2 00 2 On the Entanglement Properties of Two - Rebits Systems
Following the recent work of Caves, Fuchs, and Rungta [Found. of Phys. we discuss some entanglement properties of two-rebits systems. We pay particular attention to the relationship between entangle-ment and purity. In particular, we determine (i) the probability densities for finding pure and mixed states with a given amount of entanglement, and (ii) the mean entanglement of two-rebits states ...
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