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"I suspect that religion is a necessary evil in the childhood of our particular species. And that's one of the interesting things about contact with other intelligences: we could see what role, if any, religion plays in their development."
- Arthur C. Clarke
 |
| Gravity-assisted Subway | ||
| The fastest way between continents (that does not entail leaving the ground). |
This piece of technovelgy gives a great illustration of the fastest way to get from point A on the surface of the earth to another surface point B.
| The car shot forward and down. Corbell was on a roller coaster. He pulled out a chair arm and hung on. The car fell at a slant for what felt like half a minute. Then there was high gravity as car and tunnel curved back to horizontal. Light inside, darkness outside. Corbell was beginning to relax when the car rolled, surged to the left; rolled, surged to the right, steadied. What was that? Changing tunnels? His ears popped. Peerssa spoke. "Your speed is in excess of eight hundred kilometers per hour and still accelerating. A remarkable achievement. "How do they do it?" "At a guess, you are riding a gravity-assisted linear accelerator through an evacuated tunnel. You are about to pass beneath the Pacific Ocean..." |
| Technovelgy from A World Out of Time,
by Larry Niven. Published by Random House in 1976 Additional resources -
|
The ingenious solution is to dig a tunnel from one point to the other, using the force of gravity to provide some of the acceleration. The beauty of this approach is that, in a frictionless environment, you can speed the train on its way without having to apply any energy - and slow it down the same way!
The questions (for you engineers) are: what is the best shape (or curve) for the tunnel, and how can you avoid those pesky underground temperatures and pressures? See this article on the brachistochrone problem, one of the earliest problems posed in the calculus of variations. Newton solved this problem from scratch in one day in 1696; got your pencil? Ready, set ... go!
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and Technology from A World Out of Time
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Tech news articles related to A World Out of Time
Tech news articles related to works by Larry Niven
| Futuristic Transit Elevated Bus Never Really Worked |
| Japan Automated Cargo Transport |
| Tesla Electric 'Giga Train' Operational In Germany |
| San Francisco Autobus |
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'Hocus-pocus religions and archaic weapons are no substitute for a good blaster at your side.'
'Oscar picked up a trowel. 'I'm the tool for the mortar,' the little trowel squeaked cheerfully.'
'... he waited for the robotrix attendant to finish fueling up his ship.'
The Roujin Z system provides care to fully bedridden patients - and then some!
'Aerostat meant anything that hung in the air. This was an easy trick to pull off nowadays.'
'The Ringworld had no horizon. There was no line where the land curved away from the sky.'
'An adjustment panel outside the door would cause it to extrude various appurtenances in memory plastic...'
'Annealed in any shape for a time, and codified, the structure of that shape is retained down to the molecules.'
It's not really polite to tear the limbs off robots.
'...the imaginary companions discovered by needful children.'
