Pivoting 90 degrees , raab pans westward across the sagebrush - stubbled desert until he spots an identical tube and another building , also four kilometers distant . “ when we talk about locking the laser beam ” that shines inside those tubes , raab says , “ we mean holding the light waves steady to better than the width of an atom ? over that distance 拉布說:當(dāng)我們談到鎖?。ü艿纼?nèi)的)雷射光束時(shí),意思其實(shí)是:在光束行經(jīng)四公里的距離后,我們可以將其偏差控制在一個(gè)原子的寬度之內(nèi)。