| Past the Age of Pipes | |
|---|---|
| A torrent of red blood cells flow through your arteries and are squeezed into a single file as they enter a capillary. Each cell is pushed from other cells in the artery to go in, but is also pushed back by the cells already in the capillary (trapped by its narrow walls) and can't move until the ones in front get out of the way. This causes you to have a certain blood pressure. |  |
| Pizza shops are usually empty at certain times of the day, but then someone gets hungry and walks in. Someone else sees that person and the pizza shop and his stomach rumbles. Others see that there are people in the pizza shop and think, hmm must be good pizza, so they go in too. A bus lets off a dozen teenagers at lunch time and the pizza shop can hardly handle the sudden volume. |  |
| Rush hour traffic on the freeway pulses stop and go. Some
drive right up against the car in front. Others relax and leave large gaps. Still others
swerve in and out of the gaps. The different driving styles lead to inefficiency; they
make the traffic even worse. That's why you never see traffic jams on train tracks,
because a train is essentially a bunch of cars together that have all agreed to adopt the
same driving style. With string, blood, cars, and people, it all amounts to communication of fluid through pipes. And, not only does it become more difficult to push more fluid through the pipe as the pipe becomes full of fluid, but it becomes even more difficult as the fluid inside the pipe becomes turbulent itself (the swerving cars). This is the age of wire and string and pipes. Looking around, it's easy to understand why one might build wider roads, more checkout aisles, and take a train or plane or make laws that disallow swerving in and out of traffic. In the same vein, your tug on the string would actually never reach the moon, because each time one molecule pushes another, there's a bit of friction, and a little energy lost as heat (just like rubbing your hands together quickly). Bit by bit, the concentration of the tug is dissapated throughout space. Then along comes a strange phenomenon like superconductivity. No, superconductivity does not allow an infinite amount of fluid to pass through a pipe, but it does allow fluid to pass through the pipe without any energy loss. It's like pumping hot water from Alaska to California and never losing any heat along the way, except instead of water, we're pumping electricity. |
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