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1500 questions
57
votes
11 answers
What would be the best way to fight a duel with lightsabers?
Lightsabers are really, really different from modern swords. They have weightless blades, will cut through their targets independent of velocity, and can be turned on and off fairly quickly.
In light of these differences, it seems silly to expect…
ckersch
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57
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12 answers
Hacking the universe
Imagine the whole universe is a simulation. This should include also the people living in the universe (so more Simulacron than Matrix). And now imagine there's a group of hackers who knows (or suspects) that they live in/are part of a simulation,…
celtschk
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57
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9 answers
What would the fortifications of an underwater city look like?
Merpeople, along with other similar underwater humanoids, are often depicted as living in great cities beneath the waves. These cities have many positive things going for them: plenty of real-estate, easy to build upwards, fairly consistent weather,…
ckersch
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57
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12 answers
Infinite flat world
Instead of discovering that earth was round, we find that we live on a infinite, flat "earth".
What are some cultural implications if we were to live in a world like that (disregarding any physical impossibilities, and that gravity,…
what is sleep
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How would people conceivably escape a planet too large for chemical rockets?
I was reading this article from NASA about chemical rockets and they argue that, with a planet 50% larger than the Earth (assuming similar density, about 1.5G surface gravity), it would be impossible for chemical rockets to escape. Note that I don't…
Jarred Allen
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56
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14 answers
Is it possible to have a planetary system with planets having perfectly synchronized orbits?
I'm imagining a system with a star and something like 6-8 planets. The planets' orbits are (relatively) close to each other, and all share an orbital period that is exactly the same. I.e. the length of a year would be exactly the same on all…
nanoguy
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15 answers
Would a steam powered plane be able to cross the Atlantic ocean?
In a world where the development of internal combustion engines had been seriously delayed (for whatever reason), would it have been possible to power heavier than air aircraft by steam propulsion? And would this have been a practical proposition?…
Slarty
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56
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11 answers
For how long after an apocalypse would modern cars remain usable?
Imagine a "soft" kind of apocalypse - nothing like Earth being hit by an asteroid. In particular - 90% of human population have just disappeared (no matter why).
So there are abandoned cities and lots of vehicles, which can be used by survivors. But…
k102
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26 answers
An environment where round beds are easier to build than rectangular
Welcome to this very strange question about bedroom furniture. We've all seen the round bed in Austin Powers, and novelty beds can be round. In my Renaissance-type Earth-like world, I wanted all the beds to be round in a particular country and I…
Erin Thursby
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56
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7 answers
How fast would a sword need to be to avoid getting blood on it?
If a sword were to be swung horizontally, through the torso of a human being, how fast would it need to be to not have blood on it after the swing?
Assume the sword and its user are together able to cut through all of the proper bodily organs and…
Friendlysociopath
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10 answers
Are endothermic bombs possible?
Explosives as we know them are exothermic: they produce heat and light, or, in other words, energy is expelled.
Let's consider endothermic bombs: weapons that, upon detonation, consume heat and / or light and / or nearby electricity.
Assuming there…
Zxyrra
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56
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15 answers
How would exposing a female warrior's (mostly) bare bottom help her in combat?
There's a valid discussion about feminism and objectification of women to be had. This is not the place for it, nor do I attempt to make it one.
I noticed that in Fire Emblem: Fates (and probably other games and media, but I couldn't name any…
JesseTG
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56
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19 answers
How to introduce my perpetual motion invention to the scientific community?
Let's say I invented a perpetuum mobile. For real! A wheel spins, or a voltage is provided across two metal prongs, whatever, without it requiring any fuel or input of energy. Maybe it uses some not yet discovered law of physics, maybe it taps into…
vsz
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56
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21 answers
Why would merfolk have hair?
A classic image of mermaids are their long flowing hair that swishes in the water. But in the scientifically realistic sense this makes none. The hair would be nothing more than a nuisance to the mermaid getting tangled on rocks and offering handles…
TrEs-2b
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56
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11 answers
If an FTL spacecraft entered Earth orbit, how long would it take for humans to build a FTL spacecraft?
It’s just another average day in the life of modern day earth. Suddenly a transmission from orbit washes over the planet! Oh no! An alien race, calling themselves the “Thull”, has suddenly arrived in their spaceship and declares war on our race,…
Marky
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