The search for the curl component (B mode) in the cosmic microwave background (CMB) polarization induced by inflationary gravitational waves is described. The canonical single-field slow-roll model of inflation is presented, and we explain the quantum production of primordial density perturbations and gravitational waves. It is shown how these gravitational waves then give rise to polarization in the CMB. We then describe the geometric decomposition of the CMB polarization pattern into a curl-free component (E mode) and curl component (B mode) and show explicitly that gravitational waves induce B modes. We discuss the B modes induced by gravitational lensing and by Galactic foregrounds and show how both are distinguished from those induced by inflationary gravitational waves. Issues involved in the experimental pursuit of these B modes are described, and we summarize some of the strategies being pursued. We close with a brief discussion of some other avenues toward detecting/characterizing the inflationar...

中文翻译：

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从通货膨胀引力波中寻找 B 模式

描述了在膨胀引力波引起的宇宙微波背景 (CMB) 极化中寻找旋度分量 (B 模式)。提出了典型的单场慢滚膨胀模型，我们解释了原始密度扰动和引力波的量子产生。显示了这些引力波如何在 CMB 中引起极化。然后，我们将 CMB 偏振模式的几何分解描述为无卷曲分量（E 模式）和卷曲分量（B 模式），并明确表明引力波会诱发 B 模式。我们讨论了由引力透镜和银河前景引起的 B 模式，并展示了两者是如何与暴胀引力波引起的那些模式区分开来的。描述了这些 B 模式的实验追求所涉及的问题，我们总结了一些正在追求的策略。我们最后简要讨论了检测/表征暴胀的其他一些途径……