How can the law accommodate a further output signal, a photon or optical signal?
这定律如何适应进一步输出信号，光子或光信号？
2
As the optical precursor and main wave packet traveled through a second group of rubidium atoms, the scientists took measurements on the speed of the two photon components.
随着光前驱和主波包通过第二组铷原子，科学家就可以对这两个光子成分的速度进行测量。
3
But this study is the first to experimentally show that optical precursors exist at the single-photon level, and that they are the fastest part of the single-photon wave packet.