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1500 questions
34
votes
11 answers
Why would people in 500+ years' time be using waterways for transport?
In this picture, we see a futuristic cityscape, with what seems to me an unexpected occurrence: a fairly normal-looking barge chugging along down the river! That just looks out of place, and it brought to mind my question.
In ~500+ years, will we,…
mjr
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34
votes
12 answers
How can a human cause the Yellowstone to erupt?
The story is in contemporary earth and with same technology.
How can a single human make the Yellowstone explode with the tools available to us now (or with slightly advanced ones, but nothing too sci fi)?
The human in question wants to cause a mass…
JackIta
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34
votes
9 answers
How realistic is a dirty bomb for area-denial?
I need a city-sized (10 km2 minimum) area to be declared inaccessible for 50 years minimum.
My thought was to justify this with a dirty bomb attack of some sort. Radiological dispersal devices (RDD), while very realistic, have never been used or…
SilverCookies
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34
votes
11 answers
How would giant, secluded, underground-cave-dwelling insects get enough food?
In my world, there are underground ruins from an ancient civilization. There are giant insect creatures living in these underground cave-like ruins, ranging from the size of a large dog to the size of an elephant. They are attracted to these ruins…
anwen
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34
votes
12 answers
Why would astronauts go to space to mine asteroids?
Realistically, if we are ever going to mine asteroids, it would be drones and robots that do it, not humans, because of safety and cost reasons. What reason could justify the participation of human astronaut in asteroid mining?
M Arif Rahman Winandar
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34
votes
8 answers
Why would orcs have tusks?
Ever since Tolkien most, if not all, works of fiction including orcs portray them with tusks. Though this achieves the effect of portraying them as animalistic, what would the real world applications of this feature be? Would it cause any health…
Jordan Williams
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34
votes
22 answers
How to prevent invisible people from committing crimes?
The year is 2020, 98% of the world population are normal people with normal skills, two percent (2%) are people who have the ability to become invisible at will.
The majority of the invisible people live in peace with us, following the law. But part…
Gustavo Gabriel
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34
votes
12 answers
Would pyrokinesis be an effective defense?
I've read comics in which someone with pyrokinetic powers was able to block bullets with a sheet of fire. I have three questions
How hot would the fire have to be to melt a bullet passing through it? (fire is about 1 inch/ 2.54 cm thick)
Would this…
Josh Taub
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34
votes
5 answers
Would aliens with different visual perception be able to read our screens?
In this photography stack exchange question about why we encode pictures in RGB, several answers talk about the fact that our visual receptors are trichromatic, which is the inspiration for the RGB system. Not only is it the inspiration, it appears…
Brian Woodbury
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34
votes
36 answers
How can I make guns available, but not swords?
I'm writing a world where iron is incredibly rare and the technology to make more complex metals like steel was never developed. However, both lead and niter are incredibly common, so firearms were developed very early on and heavily influence the…
highpriestofpie
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34
votes
9 answers
Currency for my medieval game
I'm creating a game that can grow to an enormous extent, basically can be played with 2 or more and every one represents a nation. Everyone starts with a small castle, a small village and a small army and builds their way up to huge castles and…
jeyejow
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34
votes
8 answers
What environment would make leaves light blue?
What environmental effects (if any) would ever cause blue to be a colour that a plant would choose as an evolutionary advantage?
Bonus:
I'm looking for light blue plants as a preference.
EDIT:
Thank you for all the answers about how plants are…
Fulli
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34
votes
22 answers
Would cultured meat (artificial) render animal slaughter illegal?
Cultured meat, also called synthetic meat, cell-cultured meat, clean meat, etc. is a reality. It seems that the only limitation so far is the mass production of it. This might be accomplished in the next decade.
If cultured meat were cheaper and…
user31264
34
votes
13 answers
How can you find where the Earth is, if you were lost near Neptune?
While on a space mission to Neptune, you accidentally broke your tether on the way. After a couple of hours floating, you were hit by an asteroid.
You passed out.
When you are conscious again, you met me. I offer to bring you back to your home with…
padawan
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34
votes
5 answers
How to test a time machine?
Eureka!
I have a time machine in my garage and it works. I put an apple in it, close the door, set the timer, open the door to an empty machine, wait five minutes and the apple reappears. (Still tastes great too! Gotta love Honeycrisps.) I…
Green
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