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
"...a few centuries of coherent humanist thought, set against a million odd years of evolved killer ape tendency. No-one's going to give you very good odds on humanism, are they?"
- Richard Morgan
 |
| 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..." |
| 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
| CopterPack Is Robert Heinlein's 1954 Copter Harness |
| Las Vegas Tunnels To Have Autonomous Teslas |
| First Boring Passenger Station In Las Vegas |
| Tesla's 20,000 Superchargers |
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
'the registration number which the traffic control automatically photographed as she left the controlway...'
'It could maintain a steady six miles per hour...'
'Then they press one of these here thirteen buttons...'
'...without burning a single hydrocarbon molecule to injure the diseased atmosphere any further.'
'Bird-like robots now descended from the ceiling of the theatre...'
'The efficient robot waiter of the Sky Club had cleared away the remnants of an epicurean meal.'
'...in the tank the new body and the new mind and memory and life has taken almost instant form.'
'pirate three-vee satellites sanded out of orbit...'
'The atmosphere yielded its moisture with reluctance. It had to be coaxed down...'
