Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange
Join us in building a kind, collaborative learning community via our updated Code of Conduct.

Asks if a given concept is realistic in a given context. Answers should say yes or no, with supporting info. Contrast with: science-based and hard-science tags. This tag should never be the only tag on a question, because this tag frames how a question should be answered, not the topic.

0
votes
6answers
163 views

Can an alien civilization develop without money? [duplicate]

I'm designing an alien civilization and I was thinking: Could a civilization exist without money or any other sort of economy but instead do everything to help each other? Now, I know most of you will ...
0
votes
3answers
129 views

Extinction Equilibrium: 50%

The last time I asked a worldbuilding extinction question, I asked on what sorts of factors would create an extinction event in which 96% of all terrestrial species and only 70% of marine species died ...
9
votes
4answers
2k views

Could humans wipe out all remaining wild vertebrates on Earth in one year, if no effort is spared in doing so?

Humans already exterminated more than 50 % of wild vertebrates individuals since 1970 1, 2. I was wondering if it is possible to wipe out the remaining 50 % in less than a year ? Note that, in this ...
6
votes
3answers
112 views

How could embryonic diapause have naturally developed in humans?

embryonic diapause is a reproductive strategy that is used by a number of mammals. In embryonic diapause, the embryo  does not immediately implant in the uterus after sexual reproduction has created ...
16
votes
11answers
4k views

Electric power system connecting the Earth and the Moon

It’s year 2050 and within 10 years, all fossil fuels will be used up. All countries signed an agreement to approve an international construction, described as follows: A track will be built on the ...
4
votes
1answer
129 views

How can a parasite that feeds on sex take over a human biochemically?

I wanted to take a different direction with the succubi/incubi mythos and make it more grounded by turning it into a disease for a horror setting. A fungus exists today which can take over the body of ...
0
votes
5answers
112 views

Could a tribalistic society domesticate dinosaurs?

I'm working on a fictional plot, here's how it goes: A group of scientists go to explore an island that has recently been discovered. Once they get to the island they find dinosaurs. Yeah, dinosaurs ...
27
votes
19answers
7k views

If we can have “all the comforts of home” in space why would we settle planets?

This is something that is starting to bug me, I'm creating a universe in which space travel is cheap and comfortable and space habitats can be built roomy enough that no-one actually needs to live on ...
10
votes
7answers
619 views

Which part of the universe would make celestial navigation most difficult for a planet?

Premise I envisage a world of would-be navigators with roughly Bronze Age technology, sailing on ships to explore their planet. In contrast to our history of navigation where we "cracked the code" ...
2
votes
1answer
85 views

Help designing which metals are associated with specific magical powers in my magic system [on hold]

In my world, one of the magic systems involves people crushing special objects in their gauntlets to gain the dormant energy that exists within them. Essentially, imagine there are certain energy in ...
-2
votes
0answers
53 views

Would a Metallic Glass Mirror Differ From a Regular Mirror? [on hold]

There has been talk lately of turning glass into a metal, thus creating a material that would have greater strength than regular metal, not to mention the ability to store and release elastic energy. ...
7
votes
2answers
329 views

Is a medieval spoon satellite realistic?

I misread an answer to My carrier pigeons have been replaced by spoons: how can I send messages?, thinking it was referring to a network of parabolic reflector dishes made of spoons orbiting the ...
1
vote
4answers
132 views

What would happen if the quantities of silver and gold mined by humans were switched in a fantasy world?

Basically the title. What would happen if, in the world I'm writing, people have thus far found considerably more gold deposits than silver? Specifically, I'm wondering how this might affect their ...
25
votes
23answers
7k views

Why would surrounding countries not claim accessible, habitable, and unclaimed land?

I am designing a world for high-magic, epic campaign for D&D 5e. I really am feeling this map, and am trying to figure out how the different countries would interact. Right now I have nothing ...
16
votes
4answers
3k views

Is a network of spoon-launching trebuchets realistic?

On a comment to My carrier pigeons have been replaced by spoons: how can I send messages? I joke about creating a network of trebuchets to launch spoons. Is it realistic? My concerns: How far ...
30
votes
4answers
7k views

Anatomically Correct Succubus

The succubi are popularly represented as women with horns and bat-like wings. They feed on the vital energy in myths, but could a humanoid creature resembling a woman evolve and feed only on human ...
-1
votes
1answer
84 views

What rules govern which biomes can neighbor one another?

I'm working on a map of a single continent or large island, and I want it to have some distinct biomes. What are some simple rules to determine which biomes could possibly be near/adjacent to one ...
11
votes
1answer
110 views

How could an Earth-like planet develop huge pinkish-purple forests on ocean surfaces?

I'd really like to write a story taking place on an alien world that involves a totally new kingdom of life, and I'd like it to be at least somewhat realistic. The idea I have right now is a whole ...
13
votes
1answer
116 views

(Porcu)pine tree needle firing system?

Info I've created a pine tree that stabs its needles into people. Here's the way I did so: Using genetic engineering, my fictional scientists inserted keratin-producing genes into a pine tree (...
1
vote
6answers
792 views

Crashland onto a new planet: Origin of the Legal System?

I've been researching the origins of my world's legal system. I'm trying to develop it over time in a somewhat logical and organic manner and I've come to realise that I don't yet have a clear idea of ...
2
votes
2answers
137 views

How to go with “convert and convince” tactic in post-apocalypse settings?

My backstory goes like this: Russians develop deadly virus which kills you if you are not a Russian. They decided to release it in the USA to solve the cold war once and for all. However, something ...
0
votes
1answer
92 views

What would architecture and cities be like in a world were everyone was shrunk to the size of a mouse?

I have been thinking about a world were everyone is shrunk to the size of a mouse, or at least the size big enough to ride a mouse, and I was wondering what are your ideas about what cities and ...
4
votes
6answers
188 views

Could a magic-filled world have religions that are unrelated to magic?

Essentially, this is a sort of brainstorming question: Say a world has many kingdoms and cultures, and each of these have magicians who can use magic, which includes things like improving physical ...
13
votes
11answers
1k views

A reasonable scenario/mass motivation to colonize Mars for the first million of people with enterpreneural spirit

According to Elon Musk's plans/overall mission, humans could better survive as species if we inhabited more than one planet. So far so good, he proposes settling a million people in a first city ...
4
votes
3answers
159 views

How plausible is molecular disequilibrium from Ant-Man and the Wasp?

So if you haven't watched the film, basically there's this one character who suffers from a (fictional) condition referred to as “molecular disequilibrium.” As described by the character, it's a ...
9
votes
8answers
181 views

Individually applied multi-government

I have a world with 4 colossal cities. Like, more area than the earth big. They are inhabited by a population orders of magnitude greater than ours, consisting of many different species. Due to the ...
3
votes
2answers
171 views

Realistic date and dimensions for a first future space shipyard? [closed]

If I try to imagine a time and scale (mass and size) for a first space shipyard mankind would build in next decades, how would it look like in a mostly realistic scenario? Ships I think of are more ...
7
votes
4answers
206 views

The plausibility of tungsten reinforced steel Composite Metal Foam (CMF) as body armor

Hi everyone I would like to ask if this material is suitable to be used as body armor like kevlar, as I am planning to use them as armor for my novel. What are the drawbacks to this? Could the armor ...
49
votes
6answers
6k views

Could Cobalt bind to nitrogen the same way iron would to oxygen in an alien respiratory system?

I'm making this whole other alien world and I made it an ammonia world, so there is a lot of nitrogen in the atmosphere. Would nitrogen be a good gas to breathe in an ammonia world and would Cobalt be ...
9
votes
5answers
228 views

How would it be possible to fly with Talaria (winged sandals)?

The talaria is the name of the winged sandals or shoes famously worn by Hermes in Greek Mythology. If someone were to make a high tech gadget which the attached beating wings to a pair of boots, how ...
4
votes
2answers
164 views

Are folding Xiphoi practical?

I have a character that fights with a pair of xiphoi (double-edged, one-handed shortswords used by the ancient Greeks). These swords are stored in thick nylon sheaths around the character's forearms, ...
55
votes
26answers
11k views

Why would a Dystopian government promote education to its citizens, instead of ignorance?

So, there is a dystopian government called the Union of Fascist States. It controls both North and South America, the United Kingdom, and half of Africa. The NAF is the one and only party that ...
-1
votes
1answer
81 views

Planet of the Rodents: Who wins?

So, this is essentially a Rats of NIMH AU (Alternate Universe); as in canon, a group of rats are captured by scientists working for a laboratory located at the National Institute of Mental Health (...
1
vote
3answers
83 views

Repercussions of floating nuclear power station going into meltdown?

Set in an alternate 2010s/2020s, floating nuclear power station are now common as they can provide power to any city it is docked at (think along the lines of this real world example. or this ...
-1
votes
1answer
50 views

Colonial Policing via contracts. Is it a good idea?

In Warlords the outer colonies are independent from the Hegemony and full of various colonies divided between dozens of factions. In the outer colonies policing is done by the "Colonial Marshals" who ...
2
votes
4answers
207 views

How do we know that distant stars and galaxies are real?

In some universe,with physical laws the same as in ours, our world is some kind of "lab environment". Our solar system is enclosed in a balloon-like sphere with a radius of a few light-days around the ...
5
votes
6answers
217 views

Biological super skin

In this world human-like people have skin that is unbelievably difficult to cut through and I was wondering what biologically creatable material is flexible enough to act as skin but it also ...
0
votes
4answers
307 views

How can this more technologically-advanced army efficiently fight against a less developed mixed human/undead foe? [closed]

I am looking for ways that the military, described below, can face off against Desert warriors akin to Ancient Egyptians. They're not at a high level of technology, mostly using bows for ranged ...
9
votes
10answers
2k views

Dirigibles: Feasibility as (Effective) Aircraft Carriers

The flying aircraft carrier has been in the imaginations of many a writer and engineer, but to date the only true flying aircraft carrier has been USS Akron (and to a lesser extent, her sister ship, ...
3
votes
4answers
140 views

Is it possible to commit murder-suicide by hijacking a body for a short period of time? [closed]

The world is similar to that from the novel and TV series Altered Carbon, where a person's entire conscious is stored in a chip at the base of their skull and they can be transferred to different ...
5
votes
9answers
315 views

What reasons would you have to reclaim your spot if the current rulers aren't evil?

Let's say a strict monarch who ruled a kingdom of "hunters" was overthrown by a race/group of "witches" in a way that wasn't proportionate to any crime the recent ruler may have committed, but instead ...
8
votes
5answers
2k views

In what situation could royalty and organised crime lords mix?

I'm currently writing a story where privileged kids attend boarding school in order to become better leaders, however, the heir to a respectable and reclusive*empire falls for the heiress to a well-...
-5
votes
2answers
131 views

Terraforming Ganymede, is it possible?

The Hegemony has long looked upon Ganymede as a prime terraforming project for humanity. The Hegemony has the tech for large scale space production so large mirrors or sun shades are able to be built ...
-1
votes
1answer
103 views

Is it possible to run embassy single-handedly? [closed]

I'm writing a story about an elderly US ambassador who wants to retire but its stuck in a fictional hostile country, size about 30 millions . All his staff has been PNG-ed due to helping democratic ...
2
votes
2answers
115 views

What would the ecological effects of a worldwide ocean of fog be?

The skyworld I'm currently working on used to be an Earthlike planet until a supernatural disaster struck. Dense, translucent gas billowed from geysers on the surface until the ocean of fog covered ...
0
votes
3answers
144 views

How plausible are the terrain and land-forms on my fantasy map?

You might have seen me ask a few questions the last few days. Basically, I'm just looking for advice on how plausible this (very early prototype) map might be. Disclaimer: I unfortunately know rather ...
1
vote
7answers
289 views

What’s so special about virgins’ blood? [closed]

For some bizarre reason, most cultists are obsessed with opening portal, doing summoning, etc. But they also seem to share the same need of virgin’s blood for their spells. Now a smart cultist tried ...
19
votes
13answers
6k views

Would children born in winter be weaker than the ones born in other seasons?

Setting is a dark ages medieval world. Equivalent to Earth circa century V AD. Agriculture has no crop rotation, and most of the harvest is lost to plagues and pests (those damn wabbits). Would ...
6
votes
3answers
225 views

Space shipping lanes that use external systems, is it practical?

I've seen some cool art and scenes from the Cowboy Bebop which had trade lanes made up of what looks like large rings that accelerate and deccelerate a ship. I wanted to replicate a system like this ...
-5
votes
2answers
135 views

How to travel through tubes? [closed]

We are in new new York, year 3000-ish. The city is quite big but there is a new transport system. Tubes, they are everywhere. They suck you in and out: you fly in them, basically. Those tubes can be ...