论文标题
几乎量子相关性违反了所有两党的钟形不平等现象
All two-party facet Bell inequalities are violated by Almost Quantum correlations
论文作者
论文摘要
量子相关集的表征是量子信息中基本重要性的问题。在量子理论中，是否违反了每种适当（紧密的）不平等的问题，这在这方面是一个有趣的问题。在这里，我们通过表明“几乎量子”相关性违反了每一个紧密的铃铛不等式，这是对一组量子相关性的半定义编程放松，从而取得了重大进展。结果，我们表明，不承认违规量子的许多（两党相关性铃铛不平等和多种局部非本地计算游戏），包括两党相关性的铃铛不平等和多种局部非本地计算游戏，不是经典的钟声多门户的方面。为此，我们利用了由Cabello-Severini-Winter（CSW）发现的Bell相关性与图形理论Lovás-Theta集之间的有趣联系。我们还利用了图理论的剪切多层与经典相关性钟形多台之间的连接，以表明在量子理论中违反了定义下维相关多层的相关钟不等式。这些方法还使我们能够得出新颖的（几乎）量子钟的不平等，这可能是自我测试应用的独立兴趣。
The characterization of the set of quantum correlations is a problem of fundamental importance in quantum information. The question whether every proper (tight) Bell inequality is violated in Quantum theory is an intriguing one in this regard. Here, we make significant progress in answering this question, by showing that every tight Bell inequality is violated by 'Almost Quantum' correlations, a semi-definite programming relaxation of the set of quantum correlations. As a consequence, we show that many (classes of) Bell inequalities including two-party correlation Bell inequalities and multi-outcome non-local computation games, that do not admit quantum violations, are not facets of the classical Bell polytope. To do this, we make use of the intriguing connections between Bell correlations and the graph-theoretic Lovász-theta set, discovered by Cabello-Severini-Winter (CSW). We also exploit connections between the cut polytope of graph theory and the classical correlation Bell polytope, to show that correlation Bell inequalities that define facets of the lower dimensional correlation polytope are violated in quantum theory. The methods also enable us to derive novel (almost) quantum Bell inequalities, which may be of independent interest for self-testing applications.
