| My father was one of the inventors of the undersea fiber optic cable, and joined many of the cable laying missions, including the original Australia mission and several japan missions. (I forget the cable names) Our house growing up was full of cable segments, superconductors, lasers, and microscopes. I remember one day he brought home a $100,000 microscope that had been thrown away, which I proceeded to use to look at banal things like leaves and insects, but was designed to look at the ends of cut fibers. Anyway, its incredible to me how much these cables have transformed the world, and how invisible it is to all of us. Imagine if trans-continental communication relied on satellites? The global internet we have today would be much more isolated, with fiefdoms based on proximity. For those interested in a fiber science story: He once was asked to calculate the rate of seawater diffusion into glass, which he and the team found ridiculous, but I suppose it was unknown if water could soak into glass in an appreciable way over long periods of time. (Water is an important impurity to try and control) How would you measure such a thing? There's no good way to increase the rate of diffusion of water into glass, but what you can do is make fiber with excess water in the core, and heat the fiber while measuring the diffusion of water out of the core into the outer portions of the fiber. Then simple rate relations imply the rate of diffusion at sea floor conditions. I believe the result was that you would see a 1% increase in the water concentration in the fiber over a period of 10,000 years. So his instinct, that it does not matter, was incredibly correct. I hope nobody else has ever had to repeat such a measurement! |