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Questions tagged [reality-check]

Asks if a given concept is realistic in a given context. Answers should say yes or no, with supporting info. Compare this with the 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
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3answers
49 views

How could physical fitness and arcane magic be linked to each other if they operate differently?

Souls are made of chakra, which is the life force of all things. People are born with different levels of chakra that remain the same throughout life. Shamanism is a form of magic that uses your ...
3
votes
1answer
89 views

History without resource driven wars

Usually when a population overgrows it expands in search of new land and if the fields are virgin and empty they become farmland and cities, but if the fields are already occupied and the resources ...
14
votes
11answers
4k views

Could a species with a lifespan of 20 years achieve enough technological progress to reach space?

I'm current planning a story which includes a race of diminutive humanoid aliens, one of whom crash-lands on Earth. They're fully sentient, and have the same average intelligence level as humans. The ...
9
votes
8answers
3k views

Arrow proof medieval glass

In my world, I have ''classic'' knights but with helmets that have transparent visors which are strong enough to protect from arrows. So which material available in medieval times could withstand an ...
4
votes
2answers
1k views

What did shipping/storage crates look like in the Middle-Ages? [on hold]

If you search "medieval crate" on google you get 2 things: 3D crates that look suspiciously modern or you get real, chest-like boxes. I'm wondering if the latter is the norm for the time period?
20
votes
5answers
6k views

How can a person be kept alive while being periodically drained of blood?

I have invented a large machine that allows me to create monsters out of blood. These monsters are called golems and are very powerful. My plan is to produce a large number of them to include in my ...
-4
votes
3answers
114 views

Can a land-based organism get to be at least 100 ft. in length and still be plausible?

Basically, I'm trying to see if a land-based creature roughly between 50-100 ft. long could exist on Earth at the moment and still be scientifically plausible. I know that whales and other creatures ...
2
votes
3answers
138 views

Ice Age Cavalry

The history of horse domestication, according to recent research, starts somewhere on the plains of eastern Europe 6,000 years ago. Since then, cavalry had become a major turning point in Old World ...
7
votes
2answers
90 views

Could the TRAPPIST-1 planets have moons?

The TRAPPIST-1 planets are all very close to each other and thus are subjected to strong gravitational forces amongst each other and to the red dwarf they're orbiting. Would it be possible for them to ...
4
votes
2answers
254 views

City defenses against kaiju attacks?

In this series I'm mulling, kaiju have been around since prehistory, turning up off and on right up until modern times. In the near-future of this alt-history, say in the next twenty years (2040ish), ...
0
votes
3answers
1k views

Would simultaneous hermaphrodites wage war?

I have a world where populated by simultaneous hermaphrodites. Which are like human women plus male reproductive organs, penis and testicles. They could father children like human males, and bear ...
6
votes
2answers
250 views

Dragon flight muscles

So, Mark Witton had a lengthy article on why paleontologists think the Quetzalcoatlus northropi could fly. One interesting thing about it is that Witton and Habib think the Quetzalcoatlus had a 90-...
1
vote
3answers
169 views

Freezing Technology at a Civil War Level for 200 Years

Is there a way to "freeze" weapons, transportation, and communications technology at an American Civil War era level for at least 200 years? Basically, in the year 1867, two years after the end of ...
6
votes
7answers
4k views

Historical evidence of military force deliberately refusing to use firearms without practical reasons [on hold]

Well, I know the title is quite a common question when building fantasy world involving gunpowder, and it falls under the well known "Don't bring a gun to a sword fight" trope. I'm well aware there ...
-1
votes
0answers
60 views

Bacteria microbiota and alteration to human biology [on hold]

So I am sure you know, microscopic life is all around, there's some in us even now, doing things to aid our body, there's more of them than there are human cells. However, I am not as informed as I ...
8
votes
2answers
178 views

How much medical information could we gather from a wrist-worn device?

Context I have been thinking about the Pip Boy device from the Fallout series of videogames. It is a portable, wearable computer that can gather a lot of data about the user. It looks like this: And ...
0
votes
0answers
95 views

Artificial Intelligent Robots are taking control of my planet. How to stop them? [closed]

My Planet is actually 100 years in future when compared to earth's age. It got all kinds of resources and technologies when compared to an earth like planet(Even more advanced like flying cars and . ...
4
votes
2answers
243 views

Procedure for a bite from a fanged humanoid, and resulting effects

I am currently working on a story idea involving vampire-esque fanged humans, they require blood for sustenance once or twice a month, and are willing to pay. It goes through special canals, so they ...
0
votes
1answer
61 views

Could a loose galactic alliance be dismantled in a quick coup? [closed]

In my book series (link here), the planets of Aurea, Ishgabangaloodoo, and most of the eastern half of the galaxy have entered an alliance against the Tatian Empire (Caput Tatiium and most of the ...
-2
votes
1answer
95 views

How much pneumatization is possible? [closed]

So, one of the most common theories about how dragons could maybe still fly, the living gasbag theory. Basically, most of the dragon is a cavity filled with lifting gas or air, in order to reduce its ...
190
votes
14answers
22k views

Is there a single historic event which could be changed to cause the USA to use SI units?

I am time traveller with aim to make world better. Last time I went to the past, all I heard was: "Kill Hitler!" So I went to the past and I must tell you, April 1945 was pretty loud in Berlin! ...
1
vote
1answer
79 views

Macroevolution in a room

Imagine a large room, perhaps 50 metres in length and 35 in width, with its ceiling 40 metres above the floor. On this ceiling, there are LED lights, rendering the brightness of the room to look ...
7
votes
6answers
249 views

How to hinder the development of sea travel until the industrial age?

Instead of Earth as we know it, humans evolved on a slightly smaller, habitable earthlike planet with different geography. Due to the plot reasons, I would like to keep them confined to one (large) ...
1
vote
3answers
159 views

How many lashes can be received and leave scars without killing the person? [closed]

I am planning to have one of my female characters flogged by an angry/out of control male. I know that the stats will differ depending on the conditions, so I will provide those below: Her Physical ...
3
votes
5answers
179 views

Big and fast rogue planet

There is a big, very big planet that is travelling fast, very fast. It’s a rogue planet (not attached to a star system). It’s going to pass close, very close to the earth. The earth is probably going ...
0
votes
4answers
356 views

Could humans go from earth to an exoplanet 5 times the size of jupiter

If humans were to travel from earth to another planet that was an exoplanet 5 times the mass of Jupiter ("Rocky earth like planet"), would they be able to survive? Background: The planet I was ...
1
vote
3answers
91 views

Whale-Tail and Seal-Legs in One Animal

In marine mammals, there are two different body types for two different niches: A long, strong tail for all-marine whales... ...and all four legs modified into flippers for pinnipeds that feed in ...
1
vote
1answer
72 views

Volcano near river mouth

When a volcano is under the sea, but close to the coastline, it creates islands. I have a volcanic island near (less than 20km away) a river mouth. Is this feasible? I couldn't find any real example. ...
1
vote
1answer
133 views

if someone was stabbed in the heart is there a chance to be saved? [closed]

This question is related to my new Story somewhere in the plot a man is going to be stabbed directly into the chest in a fight , I would like to know how could he survive if the injury penetrate the ...
4
votes
2answers
69 views

What are some plausible formation explanations of a non-hot “Fluffy” Gas Giant planet?

So, in my research and preparation for the question I asked immediately before this one, I was introduced to the concept of "fluffy" gas giants, gas giants with significantly lower density than would ...
2
votes
2answers
138 views

Can we build a 3D maneuver gear from Attack on Titan?

Context In the animé Attack on Titan, armed forces use a special device called 3D maneuver gear (also called vertical movement gear) to move through the air. The system is based on a pair of ...
1
vote
1answer
137 views

How big of a taur do you get out of a human?

The title sort of explains what I'm asking, but here is some context; Bill shouldn't have taken that help wanted ad for the mad scientist up the street. Now his legs were gone, and replaces with ...
2
votes
6answers
212 views

Why do shapeshifters not kill their doubles before taking their form?

Ko’dor are an octopus like species that arise from the swamps of the planet Luvwa. They have the ability to transform their bodies into any form or shape they want. When a Ko’dor wants to infiltrate ...
2
votes
6answers
255 views

Competitive video games matches a possible replacement for war and conflicts? [duplicate]

Let's say by 21st century every country/faction on Earth have come to agreement that wars or conflict will be settled with some kind of online competitive video game match. The competitive game can ...
2
votes
1answer
252 views

Feasible star + planet + moon combo? Did I miss anything that makes this system wildly unstable or otherwise impossible?

Here's what I've come up with: The star: A main sequence star, roughly a sol analogue Younger than Sol (say 3-3.5 billion years old) roughly the same starting mass as Sol, but has had less time to ...
1
vote
4answers
141 views

Fastest Underwater Speed of a 2 Person Privately Built Submersible? [closed]

I'm currently in the process of writing a sci-fi underwater monster book, and I need to get specs for a commercially built two person submarine that can reach speeds of close to what a Russian Akula ...
9
votes
13answers
4k views

How are post apocalyptic police/paramilitary force funded?

Background World has had a disaster that has caused a global breakdown of society, along the lines of Fallout or The Walking Dead (90% of people have died or been turned into flesh-hungry zombies.) ...
25
votes
20answers
7k views

How to limit magic mirrors so they're not overly powerful?

Based on a set of questions by Pavel Janicek about how to address and then monetize magic mirrors in today's modern world. The short version of these magic mirrors is that any one magic mirror can ...
1
vote
1answer
84 views

What kind of impact could strip Venus and make it spin faster?

I'm trying to create plausible scenario under which we could colonize Venus. Is it possible that Venus could be hit by a planetoid and the impact strips its atmosphere and makes it spin faster? I'm ...
-4
votes
1answer
83 views

New Hologram World with touch and feel, Possible? Land, Water, Fire, Air, Sky with touch and feel Hologram? [closed]

I'm curious if it's possible for humans to create a Hologram World. Atmosphere for Hologram World: Touch and feel for all living and non living objects in the world Living Hologram objects which ...
25
votes
4answers
6k views

Oil-eating animal; possible?

I saw a movie where oil companies stumbled upon these fictional underground aquatic deep-sea animals that survived on eating and digesting the oil where they lived. They had squid/octopus-like bodies ...
-1
votes
1answer
139 views

The Underdown, part 1: Size issues [closed]

So, If I'm trying to make a borderline-isekai (trapped in an MMORPG world anime) setting, I might as well just make the game mechanics more real, like invisible walls, everywhere. The world of ...
4
votes
7answers
923 views

What possible reason for there to be no kingdom-sponsored messengers during a state of emergency?

An offical letter from the King to Baron Worldbuilding The kingdom is in turmoil. There has been an uprising among the knights and many of the nobles have been killed. Our country is in tatters! I ...
16
votes
11answers
6k views

Is this map realistic/believeable?

I'm working on this map right now. Is this map realistic/believable? The continent would be about 5 million km² and lies in the temperate climate zone. (I intended it to be smaller than Australia; my ...
2
votes
2answers
155 views

Creature to retrieve criminals and imprison them

For my world I was thinking of there being a domesticated creature that is able to swallow humans whole and keep them in a second stomach which acts as a prison. I figured it would need to be tall and ...
6
votes
10answers
373 views

How to make firearms rare while metal is still widely available.

My world is in a Napoleonic era in terms of weapons technology, but firearms are extremely expensive and rare. How do I make his believable? Im doing this because I want to keep bows, swords, spears, ...
66
votes
29answers
12k views

How to monetize magical mirrors in today's world?

This is kinda a followup question to my earlier question about magical mirrors: Magical internet - unique addressing system Two months ago, I discovered an ancient house in the middle of woods. As I ...
36
votes
18answers
8k views

Can we build a roguelike maze?

Edit: this is not a dupe because the other question asks for an everchanging maze that is built with pre-historic technology and that is impervious to engineering (i.e.: immune to drilling). Mine ...
23
votes
10answers
7k views

How could you create a 95% effective global emergency broadcasting system?

THIS IS A TEST of the Galactic Emergency Alert system No action is required. Type: Milkyway Empire The World In the near future: we discover FTL we run into some friendly aliens that are ...
0
votes
0answers
66 views

How fast to become “most wanted” in medieval world? [duplicate]

This is the question every RPG player or D&D player had in mind: "What happens if I kill them all?" So, lets ask the question: Imagine typical medieval fantasy kingdom. There is some magic and ...