Mandel L
Opt Lett. 1991 Dec 1;16(23):1882-3. doi: 10.1364/ol.16.001882.
It has long been known that the interference produced by two light beams is related both to their mutual coherence and also to the intrinsic indistinguishability of the photon paths. With the help of a decomposition of the density operator it is shown that the degree of indistinguishability equals the degree of coherence. This provides the fundamental link between the wave and the particle descriptions.
长期以来，人们一直知道两束光产生的干涉既与它们的相互相干性有关，也与光子路径的内在不可区分性有关。借助密度算符的分解表明，不可区分程度等于相干程度。这提供了波动描述与粒子描述之间的基本联系。
