signal velocity

基本解釋

In light of this finding, scientists have wondered whether single photons travel at the group velocity or the signal velocity.
在這些發(fā)現(xiàn)的基礎(chǔ)上，科學(xué)家曾經(jīng)懷疑，是否單個(gè)光子可以達(dá)到“群速度”和“信號(hào)傳播速度”。
The scientists found that the precursor wave front of a single photon always travels at c, like the signal velocity of large groups of photons.
科學(xué)家發(fā)現(xiàn)，單個(gè)光子的前驅(qū)波頭一般以光速c傳播，就像由大量光子攜帶的信號(hào)的傳播速度一樣。
Although previous studies have found that the "group velocity" of light can travel faster than c, the "signal velocity" –the speed at which information travels –cannot.
盡管先前的研究已經(jīng)證實(shí)，光的“群速度”可以超越光速c，而“信號(hào)傳播速度”——光攜帶的信息的傳播速度——不能超越光速。

In this case, the signal is a particle's momentum—that is its mass times its velocity.
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