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arXiv 1502.03088quant-ph
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贝尔不等式的分数决定性和反三角不等式的界

Bound on Bell Inequalities by Fraction of Determinism and Reverse Triangle Inequality

P. Joshi, K. Horodecki, M. Horodecki, P. Horodecki, R. Horodecki, Ben Li, S. J. Szarek, T. Szarek

摘要:

纠缠是一种资源,这是一个既定的事实。共享一个纠缠态会导致非局域关联和违反贝尔不等式。这种非局域相关性说明了量子资源相对于经典资源的优势。本文定量地研究了带$2\times n$输入的贝尔不等式.如[N]中所示。Gisin等人,Int. J. Q. Inf.5,525(2007)]量子力学相关性不能达到这种不等式的代数界。在本文中,我们揭示了这种效应的核心,我们称之为{ \it分数决定论}。证明了任何具有两方和$2 \times n$输入的量子统计都具有非零分数的决定性,并给出了它的一个定量界,然后应用它给出了具有$2\times n$输入的贝尔不等式式的一个显式的{ \it泛上界}.作为我们的主要数学工具,我们引入并证明了一个{ \it倒三角不等式},以定量的方式说明,如果一些状态远离给定的状态,那么它们的混合也是。不等式在推导决定论分数的下界时至关重要,但它本身也很有趣。

英文摘要:

It is an established fact that entanglement is a resource. Sharing an entangled state leads to non-local correlations and to violations of Bell inequalities. Such non-local correlations illustrate the advantage of quantum resources over classical resources. Here, we study quantitatively Bell inequalities with $2\times n$ inputs. As found in [N. Gisin et al., Int. J. Q. Inf. 5, 525 (2007)] quantum mechanical correlations cannot reach the algebraic bound for such inequalities. In this paper, we uncover the heart of this effect which we call the {\it fraction of determinism}. We show that any quantum statistics with two parties and $2 \times n$ inputs exhibits nonzero fraction of determinism, and we supply a quantitative bound for it. We then apply it to provide an explicit {\it universal upper bound} for Bell inequalities with $2\times n$ inputs. As our main mathematical tool we introduce and prove a {\it reverse triangle inequality}, stating in a quantitative way that if some states are far away from a given state, then their mixture is also. The inequality is crucial in deriving the lower bound for the fraction of determinism, but is also of interest on its own.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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