A nanosecond is one-billionth of a second.

1纳秒为十亿分之一秒。

youdao

This anomaly, which breaks the laws of physics, lasted a billionth of a billionth of a billionth of a second.

这种打破了物理定律的不正常现象持续了十亿分之一秒的十亿分之一的十亿分之一。

youdao

However, after the experiment described above the difference in time between the two clocks was less than a billionth of a second, which is why very accurate clocks were needed.

但是经过上述实验后，两个钟表的时间差距不到十亿分之一秒，所以需要用两个非常精准的钟表。

youdao

It can then release the light it absorbs in quick bursts that last a few femtoseconds each (with one femtosecond lasting one millionth of one billionth of a second), which is what ultrashort-pulse lasers do.

ENGADGET

We call this new imaging technology femto photography because we capture a segment of the image with a flashlight (in this case, a laser pulse) on for a few millionths of a billionth of a second (or a few femtoseconds) and an exposure time approaching a trillionth of a second.

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