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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.

2
votes
1answer
29 views

A Dozen Cubic Miles of Volcanic Ash--How Big Would the Cloud Be?

On May 18, 1980, Mount Saint Helens made American history with an eruption that took 57 human lives and killed thousands of animals. It has released only a quarter of a cubic mile of ash, but it is ...
0
votes
2answers
31 views

How would the terrain of a snow-covered mountain deter a mechanized army?

My story is set in a fortress town built below a mountain, and revolves around the struggle between the witch who protects the mountain and the tyrant who seeks to plunder it for resources (think ...
6
votes
6answers
426 views

Is it possible to remotely hack the GPS system and disable GPS service worldwide?

The title pretty much says it all. I'm wondering if it is possible through "digital" means only (aka any physical disruption of satellites is not allowed) to disable the US GPS satellite ...
0
votes
2answers
142 views

What is the upper bound for Lightspeed?

Followup to my lower bound light speed question. I was told on the Sandbox to split the lower and upper bound for light speed in different Questions. Yes they are similar but it is possible that ...
2
votes
3answers
233 views

What is the lower bound for lightspeed? [on hold]

I am investigating the possibility of modifying the speed of light in my world. Assuming that the speed of light in a vacuum can (and in my world, is) modified, what lower bound exists that would ...
5
votes
5answers
138 views

Would sentience affect the evolution of colorful display patters for attracting mates?

On another planet there is a group of organisms that have colorful display patterns allowing them to attract mates. Eventually a branch of this type of organism evolves the intelligence of early ...
20
votes
5answers
4k views

Is my plasma cannon concept viable?

I’ve developed a concept for a plasma cannon, and I need it reality-checked. The cannon would gather ammunition by pumping air into the gun through an external fan. The air would gather inside a ...
3
votes
4answers
226 views

A WMD whose destructive potential stops at the border of a country

In the Belgian comic book "De laatste Hollander" (en.: "The last of the Dutchmen"), an alien accidentally uses a WMD (a beam that lights up the entire country) to completely engulf the entire country ...
1
vote
0answers
91 views

What is the limit of Graphene CPUs? [on hold]

In the world I'm building, set roughly 350 years in the future, the humans have colonized the Solar System and other systems beyond using a hyperlane network discovered at the edges of the Solar ...
7
votes
2answers
91 views

Are these atmosphere compositions for habitation in space plausible/do they cause problems I don´t see?

On Earth, our atmosphere contains 78.09% nitrogen, 20.95% oxygen, on average around 1% water vapor at sea level, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Looking through ...
18
votes
3answers
4k views

Does water in vacuum form a solid shell or freeze solid?

I'm working on a sci-fi setting which includes an aquatic space-faring species. When a human space vessel is ruptured and depressurizes, the gas can escape rapidly and we immediately suffer from the ...
3
votes
1answer
172 views

The World is ending, but we have a time-machine [on hold]

Let's say an event is occuring that within a short timeframe makes at least the entire solarsystem uninhabitable. However, in a global effort, scientists and engineers have developed a backwards time ...
8
votes
2answers
2k views

Would cybernetic implants allow humans to use biofeedback to boost their performance to superhuman levels? If so how far could we take it?

So I was surfing this website which gives rpg stats for various fictional characters in various media, when I came across this character called "The Frenchman" who apparently uses biofeedback to boost ...
1
vote
2answers
149 views

Defense against endless hordes [on hold]

Imagine humans of the present day and an enemy who suddenly appeared (seemingly) out of nowhere. The enemy has following capabilities: Their army consist of all kinds of creatures from kind of ...
2
votes
3answers
362 views

Can a large hemispherical planet be stable? [duplicate]

I had a vision of a planet twice the size of earth sliced in half like an apple by an invisible force, one half drifting away from the other into eternity. Unlike the planet Earth, it did no longer ...
4
votes
2answers
193 views

How Would Plate Tectonics on an Inverted World Work?

Recently, I came across an inverted world map on the MapPorn Reddit made by MChainsaw. "Inverted" as in, the "continents" are now below sea level and the "ocean floors" are high and dry. (...
-1
votes
1answer
130 views

Could a black hole be used to lessen surface gravity on a Super-Earth?

Due to the moon's gravitational pull, objects at Earth's surface directly under the moon are slightly lighter. This tiny lessening of gravity would also take effect if the moon were on the exact ...
4
votes
2answers
146 views

Would advanced Plantoids be plausible? [closed]

Could it be plausible that if enough time given and favorable conditions are met, the dominant species of an alien planet could be a species of plant and by dominant I mean achieving sentience and ...
0
votes
4answers
158 views

How significantly would the course of rivers change over 10,000 years?

This one is rather straightforward. A character falls into a magically-induced coma for about 10,000 years and then wakes up to find the world around him different in quite a few ways. There's not a ...
4
votes
1answer
76 views

Solar insolation/flux's effect on biome diversity/richness on an alien world

The Questions I'm trying to answer three main questions: Does a three-axis biome chart make sense for my world? How productive/life-rich should a biome be given a specific level of solar flux (...
12
votes
5answers
3k views

How might a landlocked lake become a complete ecosystem?

Let's assume that there is a lake that has formed from snowmelt and rainfall. The lake has never been in contact with other bodies of water. How might this lake become a complete ecosystem?
29
votes
11answers
4k views

Half of living beings in the universe die: Does society survive? [closed]

Some purple person, somewhere, collected the Eternity Baubles, clicked their heels and suddenly, half of all living beings in the universe just go poof.1 The effect isn't restricted to sentient ...
-2
votes
1answer
122 views

How realistic is the travel of the Wandering Earth, would its mass be enough as energy source? [closed]

In the movie Wandering Earth, our planet travels to another sun. That is, it gets attached about 10000 engines fed by rocks. https://en.wikipedia.org/wiki/The_Wandering_Earth Given humanity could ...
4
votes
5answers
132 views

Logical explanation for why Brainbots would not retain their original identities memories

So, my setting is a post apocalyptic one, 197 years after WW3 kicked off and destroyed pretty much everything. The current date is 2259. Before WW3 started, the USA was experimenting heavily with ...
9
votes
5answers
155 views

Reality check: Is this a plausible way to breed raccoons?

You’re a lone immortal who’s decided to breed raccoons to a human-level intelligence (over the course of hundreds of thousands or millions of years). To do so, you need to both feed a significant ...
-1
votes
2answers
89 views

Laminar Flow Fountain Shelter?

Say you were stranded on an island with no shelter whatsoever, but for some odd reason you had all the supplies and water necessary to construct a laminar flow water dome as a shelter. Keep in mind -- ...
2
votes
1answer
162 views

Highest level of 1930's Technology possible [closed]

Backstory I have a character who goes back in time to plant an idea in the minds of government scientists during the 1930's. The idea is to analyze a DNA sample and recreate it for future use in the ...
12
votes
13answers
6k views

Is this state of Earth possible, after humans left for a million years?

It is the year 4056 (or probably later). The rocket with the last residents of Earth just took off, because global warming and pollution couldn't be stopped nor reverted and Earth became uninhabitable....
8
votes
6answers
383 views

How long would it take for a group of humans to travel across a continent by foot?

Think a Lord of the Rings-esque quest to save their kingdom. This quest would also involve detours, but I can just factor those in later. The continent is around the size of Australia, with a lot of ...
2
votes
2answers
116 views

Could bio-luminescent plants survive in total darkness for ~3 months annually?

If a three-month dark period was a normal, recurring, part of a 15-month calendar, and plants had evolved to be bio-luminescent, could they survive? Would only some survive and, if so, would it be ...
-1
votes
1answer
151 views

Do any of the things happening on this world actually have a chance of happening? And if they do, how long would humankind survive? [closed]

In this world, global warming has reached a tipping point. The equator has reached temperatures well over 212 degrees Fahrenheit (100 Celsius, 373 Kelvin), resulting in the "Boiling Sea". Global ...
1
vote
0answers
99 views

Is it possible for industrial revolution to happen without colonialism? [closed]

As we all know, with Christopher Columbus re-"discovering" America in 1492, the wondrous Age of Discovery began - and with it new dreams of conquest and wealth, that became realized in the way of ...
2
votes
0answers
161 views

If a boy was tattooed on his back, would the tattoo more-or-less sruvive into adulthood intact? [closed]

If a child, say, a white, ten year old boy, got a big tattoo on his upper back (read: shoulder to shoulder), would it change a lot as the child grew into adulthood? Since the early-ish industrial ...
56
votes
30answers
12k views

My perfect evil overlord plan… or is it?

Me You might call me evil but the facts are I deserve to rule all of the world, everyone & everything in it. What I already have done For years I have worked in the shadows (as much as you can ...
3
votes
5answers
520 views

What would an animal that absorbs nutrients though its skin be called? [closed]

Animals that eat meat are carnivores, animals that eat plants are herbivores, animals that will eat anything are called omnivores. But what are animals that absorb 25% of their nutrition directly from ...
2
votes
3answers
500 views

Would a Glass “Rupert Drop” Weapon be Plausible?

Can a large glass Rupert Drop somehow be manufactured into a useful and effective weapon in medieval warfare, such as a club? I've developed a society that primarily lives in the desert with sand in ...
-1
votes
1answer
113 views

Could a U.S. president change political parties? [closed]

This has intrigued me for a long time. Hypothetically, could a president-elect be able to switch political parties once they assume office? I'm aware of the ramifications and backlash they would get ...
3
votes
4answers
192 views

Could a tree build its bark out of Starlite-like material?

How could trees in an environment with 23% Oxygen (The atmosphere is identical to earth in all other respects.) grow bark with Starlite-like qualities? Starlite is a material claimed to be able to ...
2
votes
3answers
181 views

Fireproof liquids that are non-toxic to carbon based life?

What sort of fireproof liquid could be used by carbon-based life without causing harm to the organism? Whether it be absorbed from exterior sources or produced in the organism's body. I say organism ...
3
votes
1answer
78 views

Are there certain qualities needed for an animal to be tamed?

Are there certain qualities that animals need to be tamed? Let's say, for example, a quadrupedal omnivore with intelligence on par with Earth's ravens. It does exhibit opportunistic predatorial ...
3
votes
4answers
184 views

How can I make these feet spikes more sturdy?

The bone is three inches circumference at the joint and one-millimeter circumference at the tip. How might this bone support the front of an animal weighing one-hundred pounds? It runs with its legs ...
4
votes
4answers
131 views

What sort of hip bone is required for quadrupedal animals to locomote on their hind legs?

I am designing a creature that is quadrupedal but can run after prey on its hind legs. What kind of hip bone would allow for the excess stress to be put on it during bipedal locomotion? The animal is ...
2
votes
9answers
254 views

How would a fixed altitude magical Airship be propelled?

Background In my world, there are vehicles that can spatially "lock" themselves to a single altitude. The locking mechanism is a magical core, combined with runic metal bands extending around the ...
-1
votes
2answers
51 views

Focusing solar irradiation to create equatorial conditions at the poles [closed]

As I understand it, the majority of thermal energy on Earth comes as a by-product of absorbing radiant solar energy. Since the equator gets hit by rays which are almost perpendicular to the surface of ...
8
votes
2answers
219 views

Could an octopus ride a bicycle?

I'm imagining a scenario where there is a conflict between humans and intelligent octopuses. The humans' main mode of transport is the bicycle. The octopuses decide to stage a night raid whereby they ...
5
votes
2answers
80 views

How long would a creature the size of an argentinosaurus' bones last in a scrubland?

The basic idea is that a massive organism with a bone structure similar to a tortoise's dies in an open area. Then, once only bones are left, they become an open cavern with fertile soil layered on ...
10
votes
3answers
906 views

How might a mountain bowl form?

On a world similar to Earth minus size, gravity, and a mildly different atmosphere. The weather is much more violent, causing frequent dust storms. The planet is larger than Earth and is mostly ...
25
votes
9answers
7k views

I need a disease [duplicate]

I am struggling to find a disease/medical condition for my character. My character is 16-year-old female with a younger sister that doesn't have the disease. If you could please help, here is the ...
24
votes
10answers
9k views

How long would it take for people to notice a mass disappearance?

If 5 million people disappeared at the same time globally, assuming an even spread of random disappearances (not focused in any one location) how long would it be before people noticed there had been ...
3
votes
2answers
369 views

Would It Be Feasible to Hollow Mount Everest Into a Palace?

Let's say that some Oriental emperor had decreed that he should move his palatial residence from China to Everest. Specifically, he wanted Mount Everest to be his palace, which means hollowing the ...