论文标题
有条件的概率和干扰有或没有确定因果秩序的广义测量
Conditional probability and interferences in generalized measurements with or without definite causal order
论文作者
论文摘要
在广义测量理论的背景下，格里森 - 布希定理确保了相关概率函数的独特形式。最近，在Flatt等人中。物理。 Rev. A 96，062125（2017），随后的测量结果得到了处理，并通过延误Lüders规则及其概括（Kraus Update Update规则）。在这里，我们研究了随后测量的特殊情况，其中中间测量是两个测量值（A或B）的组成，以及未定义因果秩序的情况（A和B或B和A）。在这两种情况下，都可能出现干扰效应。我们表明，关联的概率不能单一写，并且其参数上的分布属性不能被视为理所当然。两个概率表达式对应于出生规则和经典概率。它们与获得中间测量的确定结果的内在可能性有关。对于不确定的因果秩序，还推导了因果不平等。在使用玩具模型的框架内研究了两种情况之间的边界，该框架是带有可移动梁分离器的马赫 - 齐汉德干涉仪。
In the context of generalized measurement theory, the Gleason-Busch theorem assures the unique form of the associated probability function. Recently, in Flatt et al. Phys. Rev. A 96, 062125 (2017), the case of subsequent measurements has been treated, with the derivation of the Lüders rule and its generalization (Kraus update rule). Here we investigate the special case of subsequent measurements where an intermediate measurement is a composition of two measurements (a or b) and the case where the causal order is not defined (a and b or b and a). In both cases interference effects can arise. We show that the associated probability cannot be written univocally, and the distributive property on its arguments cannot be taken for granted. The two probability expressions correspond to the Born rule and the classical probability; they are related to the intrinsic possibility of obtaining definite results for the intermediate measurement. For indefinite causal order, a causal inequality is also deduced. The frontier between the two cases is investigated in the framework of generalized measurements with a toy model, a Mach-Zehnder interferometer with a movable beam splitter.
