Questions tagged [science-based]
For questions that require answers based on hard science, not magic or pseudo-science, but do not require scientific citations. Contrast with the hard-science and reality-check tags. Do not use this tag as the only tag on a question because it describes how the question should be answered, not the topic.
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How could dragons be explained without magic?
Dragons are a grand classic of fantasy. For this question, let's assume we're talking about the following stereotype:
hatches from an ostrich-sized egg and can grow to mountain size if nothing limits ...
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Russian Dolls - How do they reproduce?
Warning picture showing dissected Russian Doll
My theory
I believe that Russian Dolls reproduce asexually. They are born pregnant. At the time of birth, the outer doll dies. What is now the outer ...
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What single change would have given the best chance for the Axis to win World War 2?
A common topic in alternate history fiction works is what would have happened if a major war had been won by the other side. These usually focus on the events after the war, and the change itself is ...
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Everything alive in the world dies this instant. Without bacteria to decompose anything, what happens to the remains? What does this look like?
So when I say everything, I mean everything. Humans, animals, plants, fungi, bacteria, all dead. If the bacteria and other detritovores and decomposers can't decompose anything since they themselves ...
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Why would giant mechs use melee weapons?
Mechs are really just giant usually bipedal walking tin cans with their human pilot inside. I mean, shoot the legs and they can't move much anymore. Not really realistic.
Regardless, in a futuristic ...
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What could people notice about someone who is two times as dense as a regular person?
I've got a group of magical people living mostly incognito in an ancient society. They look and act exactly the same as regular people, but they are really magicians, and a side effect of having those ...
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How would I know if I were a 1 mm tall robot?
In the 1955 science fiction short story, The Tunnel under the World
How would I know if my consciousness had been uploaded into a miniature robot living in a replica town?
What would be the most ...
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How can I ensure my Evil Tower is always stormy?
It's been a good year for me as an Evil Overlord. Lots of princess kidnapping turned into sizable ransoms, several of my Doomsday Devices were sold for high prices at auction, and my Minions have been ...
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Releasing a T-Rex into a modern ecosystem wouldn't be that bad, right?
T-Rex Forever LLC has a mating pair of Tyrannosaurus rex. They're a bit shady on how they got them, time travel, cloning...they won't say. Third-party biologists and paleontologists have examined ...
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Could a planet made completely of water exist?
In the Star Trek: Voyager episode "Thirty Days", there was a planet made completely out of water, which is the inspiration for this question. However, that planet was held together by an artificial ...
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What would make scientists realize they were on a flat world?
Scenario: While poking around in an alien ruin, scientists discover a gateway which offers instant transportation to an Earth-like world.
The Observed World: The gateway leads to an area that is ...
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Could a Dwarven Civilization Exist?
Could a Dwarven society as described by Tolkien mythology actually work? Dwarves for the purposes of this question are short, stout, bearded men and women who live primarily underground. They have a ...
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If our universe was a simulation, what could a bug look like?
Let's assume, without revoking any of today's science, that the world is a simulation.
What would a bug look like?
I'm assuming that "the eiffel tower suddenly being bent at 45°" is rather unlikely, ...
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Would intelligent life evolve any other body plan than humanoid?
Disclaimer: This question uses some liberal wording to get key ideas across. It's not meant to be academically rigorous, so please try to focus on the ideas and not the exact definitions of the terms ...
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This sword is forged from meteorite iron - but how is that any good?
You know the common trope in fantasy. Meteorite iron is amazing.
My armor is made of sky iron, made for me. A bear's armor is his soul, just as your daemon is your soul. You might as well take him ...
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How to build a trap to last the ages?
While considering Ancient Light Trigger Mechanism, it occurred to me that any ancient trap mechanism is unlikely to work very long without regular maintenance. It seems far too easy for dust to clog ...
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How fast can I flood the Netherlands entirely and permanently?
I want the Netherlands to be flooded entirely, and I want the event to be of such a scale that it goes faster than hydroengineering can keep up with. This will mean that I need a sea level rise of ...
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Would a Moon made of water pose a threat to Earth during eclipses?
Is a moon made entirely of water possible?
Could a planet made completely of water exist?
I was inspired by the above questions to ask the following:
Assume that our current Moon is replaced ...
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Is there a scientific explanation as to why aliens should look similar to us?
In almost all science-fiction stories that include alien races, said aliens are similar to humans in many ways: bipedal (and often humanoid), communicate with sounds coming out of a mouth, orient in ...
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Lembas bread (2000 Calories per bite)
In the lord of rings the elves invented an incredibly nutritious bread/biscuit, as Legolas clearly says only a small bite is just enough to satisfy the needs of an adult man for 1 day.
An adult ...
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A mosque on Mars?
Premise
Mars has been terraformed and has seen its first few stages of large-scale colonization. The colonists are middle to upper class Earthlings. Earth is not a dystopian planet per se, but Mars ...
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Why would vampires be incapable of entering a non-vampire human’s house uninvited?
I'm looking for a scientific explanation as to why vampires would be incapable of entering a human's house uninvited.
There have been many terrific scientific explanations for some of the most ...
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Are there logical gaps in the periodic table in which you could insert a new mystery element for use as a fuel?
As in the title.
We have the modern periodic table:
In a potential near (or far) future setting humanity discovers a new element which serves as the basis for a cleaner, higher energy density fuel ...
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A poison that only works if you know it is there
In the book He Drank and Saw the Spider, a poison is talked about in a metaphorical way: A person can be poisoned by putting a specific kind of spider into their cup, but the poison only works if you ...
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Conquering a Metropolis with near-zero own casualties
You have a trillion dollar/year military budget. You can buy all the toys (that are physically and financially possible to build with current technology). You can hire the manpower, command the ...
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Humans can now run 40 mph. How do I keep the stupid people alive?
Let's assume that humans can now run 40 mph and the human body can handle it. I know and understand that this is not feasible, but let's just play pretend. Naturally people would have all kinds of fun,...
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Tree Shape on a Tidally Locked World
I'm designing a tidally locked world around a red dwarf star. The habitable ring is an Earth analogue. The atmosphere and gravity are similar to Earth's, and we're going to pretend the wind is ...
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Is it worth sending a manned mission to a black hole?
Suppose we detect a stellar black hole passing near the Solar system, and we have technology and time to send a manned mission to study it.
Are there any experiments or observations that would help ...
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How to protect shops in the medieval era against thievery?
While coming up with a medieval era world, I suddenly realized that there was pretty much no defense against thievery except for patrolling city guards which to be honest probably isn't very effective....
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Is it physically possible for a planet to have seasons of different lengths?
Those of you who have read Game Of Thrones will know that in the GOT world seasons do not have a fixed duration, e.g., a winter might last three times longer than the previous one.
I find most ...
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How many people can you feed per square-kilometer of farmland?
Questions about how to feed a large population keep popping up on this website quite frequently. One obvious option is farming. But how many people can you feed per square-kilometer of farmland?
...
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Could astronauts find their bearings in the Universe after being transported 6 gigalightyears from Earth?
In my world, humanity reaches their new home among the stars by way of a portal that pops into the solar system one day. This portal instantaneously transports those who enter to a place that is ...
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Spiders In Space: How to design a space suit for an arachnid?
In my stellar empire, the sapient life of the home world are arachnids. Due to an oxygen-heavy world with certain evolutionary characteristics, spider-like beings developed intelligence and formed ...
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The opposite to Worldbuilding: World Destruction
I am looking at different ways to destroy a planet. I am assuming the planet is of a similar size and composition to the Earth just to keep things simple.
I am starting at boiling the atmosphere to ...
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What (modern) weapons could be used to destroy skeletal enemies as completely as possible?
As per the cliché, after getting hit by a truck, our protagonist finds herself in a 'swords and sorcery' fantasy world. Also as per the cliché, she is granted an overpowered ability to make her new ...
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How can I move a planet?
There are a lot of answers on Worldbuilding about how to destroy planets - just as an example - and they seem to be the method of choice for many people intent on destroying the world. My objection to ...
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Mineral that explodes when cooling down
While playing old games, I encountered a friend I knew from SciFi series and games alike, the Merculite missile. While thinking about what Merculite might actually be (and linking it to a mineral from ...
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How do I make an alien technology feel alien?
In a lot of science fiction series, such as Halo, Mass Effect and Gears of War, they show alien technology that is flatly human with a few added-on bells and whistles. It lacks the awe or feel of ...
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Can you simply scale up animals?
There have been a number of questions focusing on mythical creatures where the logical approach to answering has been to scale up an existing animal. For example dragon's wings can be extrapolated ...
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How can powerful telekinesis avoid violating Newton's 3rd Law?
Characters with powerful telekinesis are portrayed as being able to exert a superhuman force using only their minds. For example, they can throw a car.
Based on what I remember from high school ...
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How to harness Jupiter's gravitational energy?
I am currently orbiting Jupiter, the rent is pretty cheap and the view is magnificent.
However, my former electricity provider refuses to connect me to earth's grid for petty reasons like "are you ...
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How could a natural road form across a sea?
BACKGROUND
I'd like my earth-like world to have a naturally formed narrow strip of land that bridges a major sea. Now, before anyone rushes off to comment about island chains and land bridges, I'll ...
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How can an unimaginably huge life form reliably communicate with mortals?
The Starmakers are vast. Stars are their seeds, supernovae their hatching. Unimaginable millennia pass before they even begin to blink at their neighbours, and they do not die, merely pass along their ...
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What single change would have given the best chance for the Allies to win the Battle of France in early WWII
The obvious WWII alternate history question is how could the Axis have won. Let's try something different this time.
The Battle of France was a big gamble for the Third Reich. They sent more or less ...
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Would earthlike planets in other solar systems have well-known Earth gemstones such as rubies, emeralds and sapphires?
I'm currently working on a conworld that has never had any contact with Earth, and I'd like to create words for iconic gemstones, such as rubies, emeralds and sapphires.
However, I can't help but ...
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How can I hide my island?
I'm a supervillain. I have no name, but you can rest assured my intentions are dubious and always result in general harm.
My biggest problem these days are these pesky superheroes keep finding my ...
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Let's weaponize jellyfish
Jellyfish are... weird. They're clear, slimy, and can sting after death. Sounds perfect for experimentation, so let's weaponize them!
Consider a hypothetical world where jellyfish are extremely common ...
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Are there any ways to allow some form of FTL travel without allowing time travel?
Faster than light travel is a really cool thing to have in sci-fi settings. It allows humans, in relatable time scales, to travel the galaxy and see a variety of worlds. It allows for conflicts ...
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Could a disaster kill all (human) life on Earth but leave astronauts in low orbit alive long enough to return?
There are plenty of threats out there that could terminate all life on our little planet in varying amounts of time (Solar flares, meteors and supernovas to name a few).
Are there any disasters that ...
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The land grows evil and corrupted ... but why?
BACKGROUND
A corruption has seized hold of the land, turning great swathes of it into a poisonous waste that humans may only enter at their peril. Perhaps all who enter the waste grow sick or go mad, ...
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