The Siegert relation relates the electric field and intensity correlations of light, under given assumptions. After a brief history of intensity correlations, we give a derivation of the relation. Then we present an experiment, which can be easily adapted for an undergraduate setup, and that allows measuring both field and intensity correlations at the same time, thus providing a direct test of the Siegert relation. As a conclusion, we discuss typical situations where the relation fails.

中文翻译：

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连接场和强度相关性：Siegert 关系及其测试方法

在给定的假设下，Siegert 关系涉及光的电场和强度相关性。在强度相关性的简要历史之后，我们给出关系的推导。然后我们提出了一个实验，它可以很容易地适应本科设置，并且允许同时测量场和强度相关性，从而提供对 Siegert 关系的直接测试。作为结论，我们讨论了关系失败的典型情况。