CLOVER: Measuring gravitational waves from inflation.

宇宙微波背景辐射（Cosmic Microwave Background，CMB）是宇宙早期发出的辐射。它告诉我们宇宙在时间上有一个开端。迄今为止对CMB强度的测量与宇宙起源的暴胀理论是一致的，但仍有许多东西需要学习。我们在天空中看到的结构--星系、星系团和超星系团--是由宇宙存在的一秒的前几分之一期间指数膨胀阶段时空的原始量子涨落产生的。这些原始的量子涨落是引力波背景的来源，而引力波又会在CMB的偏振上产生一个特征，称为B模式。三叶草是一项由英国领导的实验，位于南极大陆，将首次提供对这种B模式特征光谱的高灵敏度测量。为了实现这种高灵敏度，英国正在开发新的世界级技术。

The Cosmic Microwave Background (CMB) is a radiation emitted in the very early Universe. It tells us that the Universe has a beginning in Time. Measurements to date of the intensity of the CMB are consistent with the inflationary theory of the origin of the Universe, however there is much still to learn. Structures - galaxies, clusters and super-clusters of galaxies - that we see in the sky are generated by primordial quantum fluctuations of space-time during an exponential expansion phase during the first fraction of a second of the existance of the Universe. These primordial quantum fluctuations are the source of a background of gravitational waves, which in turn generates a signature on the polarisation of the CMB, known as B-modes. CLOVER, a UK-led experiment based in the Antarctic continent, will provide the first, high-sensitivity, measurement of the spectrum of this B-mode signature. To achieve this high-sensitivity, new world-class technologies are being developed in the UK.