论文标题
量子状态的Schmidt数不能总是由设备独立认证
The Schmidt number of a quantum state cannot always be device-independently certified
论文作者
论文摘要
量子基础和量子信息理论的重大挑战之一是纠缠与违反贝尔不平等之间关系的表征。众所周知，在特定情况下，这两者的行为可能会有所不同，从限制的铃铛场景中的局部隐藏变化模型到纠缠量子状态，到最大程度地侵犯了与最大纠缠不同意的贝尔不平等现象。在本文中，我们提出了一个简单的证据，表明存在量子状态，其纠缠含量（按照Schmidt编号测量）不能对任何副本上的所有可能的顺序测量进行与设备无关的认证。虽然更大的问题：\ textit {纠缠的存在始终是独立于设备的认证吗？}仍然开放，我们提供的证据表明，即使超出了标准的铃铛场景，也并非总是可能量化纠缠设备无关的纠缠。
One of the great challenges of quantum foundations and quantum information theory is the characterisation of the relationship between entanglement and the violation of Bell inequalities. It is well known that in specific scenarios these two can behave differently, from local hidden-variable models for entangled quantum states in restricted Bell scenarios, to maximal violations of Bell inequalities not concurring with maximal entanglement. In this paper we put forward a simple proof that there exist quantum states, whose entanglement content, as measured by the Schmidt number, cannot be device-independently certified for all possible sequential measurements on any number of copies. While the bigger question: \textit{can the presence of entanglement always be device-independently certified?} remains open, we provide proof that quantifying entanglement device-independently is not always possible, even beyond the standard Bell scenario.
