Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Latest By
Category:
Armor
Artificial
Intelligence
Biology
Clothing
Communication
Computers
Culture
Data Storage
Displays
Engineering
Entertainment
Food
Input Devices
Lifestyle
Living Space
Manufacturing
Material
Media
Medical
Miscellaneous
Robotics
Security
Space Tech
Spacecraft
Surveillance
Transportation
Travel
Vehicle
Virtual
Person
Warfare
Weapon
Work
"I operate by a code that makes me responsible for what I do, makes me definitely, directly, genuinely responsible. I am precisely the kind of person I made myself out to be."
- Harlan Ellison
 |
| 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!
Comment/Join this discussion ( 1 ) | RSS/XML | Blog This |
Additional
resources:
More Ideas
and Technology from A World Out of Time
More Ideas
and Technology by Larry Niven
Tech news articles related to A World Out of Time
Tech news articles related to works by Larry Niven
| CORLEO Robotic Horse Concept Looks Ready To Ride |
| Futuristic Transit Elevated Bus Never Really Worked |
| Japan Automated Cargo Transport |
| Tesla Electric 'Giga Train' Operational In Germany |
Want to Contribute an
Item?
It's easy:
Get the name of the item, a
quote, the book's name and the author's name, and Add
it here.
| <Previous | Next> |
|
|
|
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Science Fiction Invention Timeline, or see what's New.
|
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
'Their only check on the growth and development of Vulcan 3 lay in two clues: the amount of rock thrown up to the surface... and the amount of the raw materials and tools and parts which the computer requested.'
'I guess there's nobody round this table who doesn't have a Crosswell [tapeworm] working for him in the small intestine.'
'Figments of his mind in one sense, of course, for he had shaped them...'
'So the parent drone carries a spotter that it launches...'
'...nurse drones that would cruise around dumping large amounts of power into randomly selected pods.'
'It's done with a flip of the third joint of the tentacle on the down beat.'
'...for months Grantline bores had dug into the cliff.'
'I hope all those other cars are on automatic,' he said anxiously.
'It’s smart enough to go wrong in very complicated ways, but not smart enough to help us find out what’s wrong.'
