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In 2012, a team of Japanese and Danish researchers set a world record,
在2012年，由日本和丹麦研究人员组成的小组创下了一项世界记录，
transmitting 1 petabit of data -- that's 10,000 hours of high-def video -- over a fifty-kilometer cable, in a second.
在一根50千米的电缆上传输1Pbit的数据用时只有1秒--这相当于一万小时的高清视频。
This wasn't just any cable.
这可不是普通电缆。
It was a souped-up version of fiber optics -- the hidden network that links our planet and makes the internet possible.
这是一种增强型光纤--组成了连接我们的星球、让互联网成为可能的隐形网络。
For decades, long-distance communications between cities and countries were carried by electrical signals, in wires made of copper.
几十年来，城市或国家间的长距离沟通，都由经铜线传导的电信号承载。
This was slow and inefficient, with metal wires limiting data rates and power lost as wasted heat.
这种方式慢而低效，金属线限制了数据传输速率，而且电线发热造成功率损耗。
But in the late 20th century, engineers mastered a far superior method of transmission.
但在20世纪晚期，工程师掌握了一种更好的传输方式。
Instead of metal, glass can be carefully melted and drawn into flexible fiber strands,
不再使用金属导线，而是将玻璃精心融化后拉成柔韧的纤维，
hundreds of kilometers long and no thicker than human hair.
纤维可长至几百公里，和人的头发一样细。
And instead of electricity, these strands carry pulses of light, representing digital data.
纤维不再传递电信号，而是传递代表数字信号的光脉冲。
But how does light travel within glass, rather than just pass through it?
但光如何在玻璃纤维中传导而不会穿出去呢？
The trick lies in a phenomenon known as total internal reflection.
秘密就在于光全内反射现象。
Since Isaac Newton's time, lensmakers and scientists have known that light bends when it passes between air and materials like water or glass.
自艾萨克·牛顿时代以来，眼镜制造商和科学家们已经知道，光穿过空气和其他介质如水或玻璃的交界时产生折射。
When a ray of light inside glass hits its surface at a steep angle, it refracts, or bends as it exits into air.
当一束穿过玻璃的光以很陡的角度抵达玻璃表面时，它会发生折射，即弯折后进入空气中。
But if the ray travels at a shallow angle, it'll bend so far that it stays trapped, bouncing along inside the glass.
但如果光束角度很小时，它会产生反射并留在玻璃中，在琉璃中来回反弹。
Under the right condition, something normally transparent to light can instead hide it from the world.
在特定条件下，透光的东西就能把光藏在其内，不会让光穿透出来。
Compared to electricity or radio, fiber optic signals barely degrade over great distances
与电信号或无线信号相比，光纤信号在长距离传输中几乎没有损耗，
a little power does scatter away, and fibers can't bend too sharply, otherwise the light leaks out.
会散失一点能量，且光纤不能大角度弯折，否则光信号会外泄。
Today, a single optical fiber carries many wavelengths of light, each a different channel of data.
如今一根光纤可承载不同波长的光信号，不同波长传输不同的数据。
And a fiber optic cable contains hundreds of these fiber strands.
一段光缆包含几百根光纤。
Over a million kilometers of cable crisscross our ocean floors to link the continents
大洋底纵横交错的百万公里光缆，它们将各大洲连在一起，
that's enough to wind around the Equator nearly thirty times.
光缆总长足以绕赤道差不多30圈。
With fiber optics, distance hardly limits data, which has allowed the internet to evolve into a planetary computer.
有了光纤，数据传输不再受距离的限制，而互联网则发展为全球计算机。
Increasingly, our mobile work and play rely on legions of overworked computer servers,
我们的移动工作和娱乐更加依赖位于大量超负荷工作的计算机服务器，
warehoused in gigantic data centers flung across the world.
它们存在于世界各地的超大数据中心。
This is called cloud computing, and it leads to two big problems: heat waste and bandwidth demand.
这就是云计算，而它引发了两个大问题：热损耗和带宽要求。
The vast majority of internet traffic shuttles around inside data centers,
多数网络传输发生在各数据中心内部，
where thousands of servers are connected by traditional electrical cables.
而这些服务器都是由传统电缆连接。
Half of their running power is wasted as heat.
一半的运行功率以热损耗方式浪费掉了。
Meanwhile, wireless bandwidth demand steadily marches on,
与此同时，无线带宽需求稳步增长，
and the gigahertz signals used in our mobile devices are reaching their data delivery limits.
移动设备中使用的千兆赫兹信号已达到其数据传输极限。
It seems fiber optics has been too good for its own good, fueling overly-ambitious cloud and mobile computing expectations.
光纤为通信领域带来的革命，助长了对云计算和移动计算的过高预期。
But a related technology, integrated photonics, has come to the rescue.
但集成光学这项相关技术应运而生。
Light can be guided not only in optical fibers, but also in ultrathin silicon wires.
光不仅可以在光纤中传导，也可以在超薄硅中传导。
Silicon wires don't guide light as well as fiber.
光在超薄硅中的传导性不及光纤。
But they do enable engineers to shrink all the devices in a hundred kilometer fiber optic network
但它们让工程师能够将百公里光纤网络中的设备，
down to tiny photonic chips that plug into servers and convert their electrical signals to optical and back.
集成到可插入服务器的微小光子芯片中，实现电信号和光信号互转。
These electricity-to-light chips allow for wasteful electrical cables in data centers to be swapped out for power-efficient fiber.
有了光电转换芯片，数据中心中就可以将损耗大的电缆换成节能光纤。
Photonic chips can help break open wireless bandwidth limitations, too.
光子芯片也打破了无线带宽限制。
Researchers are working to replace mobile gigahertz signals with terahertz frequencies, to carry data thousands of times faster.
研究人员正在努力用太赫兹频率取代移动千兆赫信号，将数据传输速度提高数千倍。
But these are short-range signals: they get absorbed by moisture in the air, or blocked by tall buildings.
但它们是短距离无线信号：容易被空气中的水分吸收，或被高层建筑物阻挡。
With tiny wireless-to-fiber photonic transmitter chips distributed throughout cities, terahertz signals can be relayed over long-range distances.
通过分布在整个城市的无线-光纤光子发射器微型芯片，太赫兹信号可以进行远距离传输。
They can do so via a stable middleman, optical fiber, and make hyperfast wireless connectivity a reality.
中间传输借助稳定的光纤来实现，让超高速无线连接成为现实。
For all of human history, light has gifted us with sight and heat,
在人类历史上，光带给我们热并照亮世界，
serving as a steady companion while we explored and settled the physical world.
陪伴我们探索物理世界并定居下来。
Now, we've saddled light with information and redirected it to run along a fiber optic superhighway
现在，我们给光插上了信息的翅膀，让它沿着光纤超高速公路飞奔，
with many different integrated photonic exits -- to build an even more expansive, virtual world.
配备多种集成光子出口，去构建一个更加广阔的虚拟世界。
