[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.02,0:00:08.48,Default,,0000,0000,0000,,In 2012,
Dialogue: 0,0:00:08.48,0:00:13.14,Default,,0000,0000,0000,,a team of Japanese and Danish researchers\Nset a world record,
Dialogue: 0,0:00:13.14,0:00:15.72,Default,,0000,0000,0000,,transmitting 1 petabit of data—
Dialogue: 0,0:00:15.72,0:00:19.01,Default,,0000,0000,0000,,that’s 10,000 hours of high-def video—
Dialogue: 0,0:00:19.01,0:00:22.53,Default,,0000,0000,0000,,over a fifty-kilometer cable, in a second.
Dialogue: 0,0:00:22.53,0:00:24.43,Default,,0000,0000,0000,,This wasn’t just any cable.
Dialogue: 0,0:00:24.43,0:00:27.47,Default,,0000,0000,0000,,It was a souped-up version \Nof fiber optics—
Dialogue: 0,0:00:27.47,0:00:29.77,Default,,0000,0000,0000,,the hidden network that links our planet
Dialogue: 0,0:00:29.77,0:00:32.24,Default,,0000,0000,0000,,and makes the internet possible.
Dialogue: 0,0:00:32.24,0:00:33.12,Default,,0000,0000,0000,,For decades,
Dialogue: 0,0:00:33.12,0:00:36.50,Default,,0000,0000,0000,,long-distance communications \Nbetween cities and countries
Dialogue: 0,0:00:36.50,0:00:38.55,Default,,0000,0000,0000,,were carried by electrical signals,
Dialogue: 0,0:00:38.55,0:00:40.27,Default,,0000,0000,0000,,in wires made of copper.
Dialogue: 0,0:00:40.27,0:00:42.24,Default,,0000,0000,0000,,This was slow and inefficient,
Dialogue: 0,0:00:42.24,0:00:47.66,Default,,0000,0000,0000,,with metal wires limiting data rates \Nand power lost as wasted heat.
Dialogue: 0,0:00:47.66,0:00:49.60,Default,,0000,0000,0000,,But in the late 20th century,
Dialogue: 0,0:00:49.60,0:00:53.60,Default,,0000,0000,0000,,engineers mastered a far superior method\Nof transmission.
Dialogue: 0,0:00:53.60,0:00:55.06,Default,,0000,0000,0000,,Instead of metal,
Dialogue: 0,0:00:55.06,0:01:00.15,Default,,0000,0000,0000,,glass can be carefully melted and \Ndrawn into flexible fiber strands,
Dialogue: 0,0:01:00.15,0:01:04.54,Default,,0000,0000,0000,,hundreds of kilometers long \Nand no thicker than human hair.
Dialogue: 0,0:01:04.54,0:01:06.24,Default,,0000,0000,0000,,And instead of electricity,
Dialogue: 0,0:01:06.24,0:01:11.49,Default,,0000,0000,0000,,these strands carry pulses of light, \Nrepresenting digital data.
Dialogue: 0,0:01:11.49,0:01:16.23,Default,,0000,0000,0000,,But how does light travel within glass, \Nrather than just pass through it?
Dialogue: 0,0:01:16.23,0:01:21.51,Default,,0000,0000,0000,,The trick lies in a phenomenon known \Nas total internal reflection.
Dialogue: 0,0:01:21.51,0:01:23.17,Default,,0000,0000,0000,,Since Isaac Newton’s time,
Dialogue: 0,0:01:23.17,0:01:26.80,Default,,0000,0000,0000,,lensmakers and scientists have \Nknown that light bends
Dialogue: 0,0:01:26.80,0:01:31.59,Default,,0000,0000,0000,,when it passes between air and \Nmaterials like water or glass.
Dialogue: 0,0:01:31.59,0:01:36.24,Default,,0000,0000,0000,,When a ray of light inside glass hits its \Nsurface at a steep angle,
Dialogue: 0,0:01:36.24,0:01:39.97,Default,,0000,0000,0000,,it refracts, or bends \Nas it exits into air.
Dialogue: 0,0:01:39.97,0:01:42.96,Default,,0000,0000,0000,,But if the ray travels at a shallow angle,
Dialogue: 0,0:01:42.96,0:01:46.03,Default,,0000,0000,0000,,it’ll bend so far that it stays trapped,
Dialogue: 0,0:01:46.03,0:01:48.95,Default,,0000,0000,0000,,bouncing along inside the glass.
Dialogue: 0,0:01:48.95,0:01:50.32,Default,,0000,0000,0000,,Under the right condition,
Dialogue: 0,0:01:50.32,0:01:55.55,Default,,0000,0000,0000,,something normally transparent to light\Ncan instead hide it from the world.
Dialogue: 0,0:01:55.55,0:01:57.99,Default,,0000,0000,0000,,Compared to electricity or radio,
Dialogue: 0,0:01:57.99,0:02:01.78,Default,,0000,0000,0000,,fiber optic signals barely degrade \Nover great distances—
Dialogue: 0,0:02:01.78,0:02:04.05,Default,,0000,0000,0000,,a little power does scatter away,
Dialogue: 0,0:02:04.05,0:02:06.58,Default,,0000,0000,0000,,and fibers can’t bend too sharply,
Dialogue: 0,0:02:06.58,0:02:08.49,Default,,0000,0000,0000,,otherwise the light leaks out.
Dialogue: 0,0:02:08.49,0:02:12.79,Default,,0000,0000,0000,,Today, a single optical fiber carries many\Nwavelengths of light,
Dialogue: 0,0:02:12.79,0:02:15.26,Default,,0000,0000,0000,,each a different channel of data.
Dialogue: 0,0:02:15.26,0:02:19.47,Default,,0000,0000,0000,,And a fiber optic cable contains hundreds \Nof these fiber strands.
Dialogue: 0,0:02:19.47,0:02:23.44,Default,,0000,0000,0000,,Over a million kilometers of cable \Ncrisscross our ocean floors
Dialogue: 0,0:02:23.44,0:02:25.04,Default,,0000,0000,0000,,to link the continents—
Dialogue: 0,0:02:25.04,0:02:29.44,Default,,0000,0000,0000,,that’s enough to wind around the \NEquator nearly thirty times.
Dialogue: 0,0:02:29.44,0:02:30.63,Default,,0000,0000,0000,,With fiber optics,
Dialogue: 0,0:02:30.63,0:02:32.85,Default,,0000,0000,0000,,distance hardly limits data,
Dialogue: 0,0:02:32.85,0:02:36.85,Default,,0000,0000,0000,,which has allowed the internet to evolve\Ninto a planetary computer.
Dialogue: 0,0:02:36.85,0:02:37.65,Default,,0000,0000,0000,,Increasingly,
Dialogue: 0,0:02:37.65,0:02:43.22,Default,,0000,0000,0000,,our mobile work and play rely on legions \Nof overworked computer servers,
Dialogue: 0,0:02:43.22,0:02:47.16,Default,,0000,0000,0000,,warehoused in gigantic data centers \Nflung across the world.
Dialogue: 0,0:02:47.16,0:02:49.08,Default,,0000,0000,0000,,This is called cloud computing,
Dialogue: 0,0:02:49.08,0:02:51.36,Default,,0000,0000,0000,,and it leads to two big problems:
Dialogue: 0,0:02:51.36,0:02:54.14,Default,,0000,0000,0000,,heat waste and bandwidth demand.
Dialogue: 0,0:02:54.14,0:02:58.84,Default,,0000,0000,0000,,The vast majority of internet traffic \Nshuttles around inside data centers,
Dialogue: 0,0:02:58.84,0:03:03.54,Default,,0000,0000,0000,,where thousands of servers are connected \Nby traditional electrical cables.
Dialogue: 0,0:03:03.54,0:03:06.29,Default,,0000,0000,0000,,Half of their running power \Nis wasted as heat.
Dialogue: 0,0:03:06.29,0:03:10.45,Default,,0000,0000,0000,,Meanwhile, wireless bandwidth demand \Nsteadily marches on,
Dialogue: 0,0:03:10.45,0:03:13.54,Default,,0000,0000,0000,,and the gigahertz signals used in our \Nmobile devices
Dialogue: 0,0:03:13.54,0:03:16.34,Default,,0000,0000,0000,,are reaching their data delivery limits.
Dialogue: 0,0:03:16.34,0:03:19.87,Default,,0000,0000,0000,,It seems fiber optics has been too good\Nfor its own good,
Dialogue: 0,0:03:19.87,0:03:24.58,Default,,0000,0000,0000,,fueling overly-ambitious cloud and mobile\Ncomputing expectations.
Dialogue: 0,0:03:24.58,0:03:29.83,Default,,0000,0000,0000,,But a related technology, integrated \Nphotonics, has come to the rescue.
Dialogue: 0,0:03:29.83,0:03:32.86,Default,,0000,0000,0000,,Light can be guided not \Nonly in optical fibers,
Dialogue: 0,0:03:32.86,0:03:36.22,Default,,0000,0000,0000,,but also in ultrathin silicon wires.
Dialogue: 0,0:03:36.22,0:03:39.55,Default,,0000,0000,0000,,Silicon wires don’t guide light\Nas well as fiber.
Dialogue: 0,0:03:39.55,0:03:42.12,Default,,0000,0000,0000,,But they do enable engineers to shrink
Dialogue: 0,0:03:42.12,0:03:45.60,Default,,0000,0000,0000,,all the devices in a hundred kilometer \Nfiber optic network
Dialogue: 0,0:03:45.60,0:03:49.24,Default,,0000,0000,0000,,down to tiny photonic chips that plug\Ninto servers
Dialogue: 0,0:03:49.24,0:03:53.33,Default,,0000,0000,0000,,and convert their electrical signals \Nto optical and back.
Dialogue: 0,0:03:53.33,0:03:59.43,Default,,0000,0000,0000,,These electricity-to-light chips allow for\Nwasteful electrical cables in data centers
Dialogue: 0,0:03:59.43,0:04:02.81,Default,,0000,0000,0000,,to be swapped out for \Npower-efficient fiber.
Dialogue: 0,0:04:02.81,0:04:07.38,Default,,0000,0000,0000,,Photonic chips can help break open \Nwireless bandwidth limitations, too.
Dialogue: 0,0:04:07.38,0:04:10.86,Default,,0000,0000,0000,,Researchers are working to replace mobile\Ngigahertz signals
Dialogue: 0,0:04:10.86,0:04:12.65,Default,,0000,0000,0000,,with terahertz frequencies,
Dialogue: 0,0:04:12.65,0:04:15.58,Default,,0000,0000,0000,,to carry data thousands of times faster.
Dialogue: 0,0:04:15.58,0:04:17.62,Default,,0000,0000,0000,,But these are short-range signals:
Dialogue: 0,0:04:17.62,0:04:19.72,Default,,0000,0000,0000,,they get absorbed by moisture in the air,
Dialogue: 0,0:04:19.72,0:04:21.96,Default,,0000,0000,0000,,or blocked by tall buildings.
Dialogue: 0,0:04:21.96,0:04:25.33,Default,,0000,0000,0000,,With tiny wireless-to-fiber photonic \Ntransmitter chips
Dialogue: 0,0:04:25.33,0:04:27.00,Default,,0000,0000,0000,,distributed throughout cities,
Dialogue: 0,0:04:27.00,0:04:31.43,Default,,0000,0000,0000,,terahertz signals can be relayed over \Nlong-range distances.
Dialogue: 0,0:04:31.43,0:04:34.07,Default,,0000,0000,0000,,They can do so via a stable middleman,
Dialogue: 0,0:04:34.07,0:04:39.43,Default,,0000,0000,0000,,optical fiber, and make hyperfast \Nwireless connectivity a reality.
Dialogue: 0,0:04:39.43,0:04:41.30,Default,,0000,0000,0000,,For all of human history,
Dialogue: 0,0:04:41.30,0:04:43.89,Default,,0000,0000,0000,,light has gifted us with sight and heat,
Dialogue: 0,0:04:43.89,0:04:49.18,Default,,0000,0000,0000,,serving as a steady companion while we\Nexplored and settled the physical world.
Dialogue: 0,0:04:49.18,0:04:52.81,Default,,0000,0000,0000,,Now, we’ve saddled light with information\Nand redirected it
Dialogue: 0,0:04:52.81,0:04:55.76,Default,,0000,0000,0000,,to run along a fiber optic superhighway—
Dialogue: 0,0:04:55.76,0:04:59.10,Default,,0000,0000,0000,,with many different integrated \Nphotonic exits—
Dialogue: 0,0:04:59.10,0:05:02.88,Default,,0000,0000,0000,,to build an even more expansive, \Nvirtual world.