Boosting the Web: Fiber Optic Cables and the Speed of Light

Anyone who survived high school physics class will probably recall silly posters on the wall postulating the Speed of Light, “c”, as a speed limit—as SiliconANGLE’s Mark Hopkins says, “299,792,458 metres per second. IT’S THE LAW.” Information is channeled across fiber optic cables using light, which means that for any single bit of information we’re bottlenecked by that speed limit, however, no current cable reaches the actual full speed of light in a vacuum because fiber optic cables are not empty…

So, when Denton Gentry over at the Geekhold blog Coding Relic suggests that we “increase the speed of light” he doesn’t mean that we attempt to change the apparently immutable laws of physics—he wants us to change the fiber optic medium so that it doesn’t impede light traffic as much.

100 Gigabit Ethernet is nearly done, with products already available on the market. Research into technologies for Terabit links is ramping up now, including one at UCSB which triggered this musing. Dan Blumenthal, a UCSB professor involved in the effort, said that new materials for the fiber optics might be considered: “We won’t start out with that, but it’ll move in that direction,”(quoting from Light Reading).

Fiber with a 10% lower refractive index would increase the speed of light in the medium by 10%. It would decrease the round trip time across the Pacific from ~100 msec to ~90 msec. One of my favorite Star Trek lines is from Déjà Q, a casual suggestion to “Change the gravitational constant of the universe.” This is a case where we can make the web faster by changing the speed of light, though we need only do so within fiber optic cables and not the entire universe.

Right now, talking to Japan from the US will be a little bit slower than talking to California from Arizona—distance is a factor—but as materials science gets better and better we should be able to produce cables that will allow light to travel faster across the Pacific. Even an 10-percent increase will produce a dramatic effect on the amount of bandwidth that can be pressed through those cables.

It’s either we work on making our communication faster, little by little, with the technology we have.

Or we develop an ansible and call the whole thing off. (With all due credit to Orson Scott Card and Ursula K. Le Guin.) I am guessing we’ll go the conventional route, although the science fiction nerds in all of us will continue to drool at the idea of instant communication.