Questions tagged [hard-science]
REVIEW THE WIKI BEFORE USING THIS TAG! For questions that require unequivocal proof that answers are correct through the use of equations, empirical evidence, scientific papers, etc. Compare to: science-fiction, science-based and internal-consistency. This tag may not be used alone. This tag may not be used with the science-fiction, science-based, or internal-consistency tags. Flag your question for moderator attention once posted.
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How could humans repeatedly lose their latest memories
My story requires a team of human explorers on a far-away planet to repeatedly lose their latest few months worth of memories through some natural phenomenon (or perhaps equipment malfunction) while ...
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4
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1
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Size cap of vertebrate fliers on "Flyers' World" (10atm, 0.5g)
On Earth, unlike what's often claimed, the largest current flying birds don't approach the size limit for flight with Earthly biology. Quetzalcoatlus might be getting close to the limit, though. A big ...
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2
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How fast would winds be on a terrestrial planet with a 12 hour day?
I'm designing a high gravity (1.38g) world with a fast rotation rate (12 hours). I think the circulation cells would be stronger with a faster rotation rate, but I'm trying to figure out what a ...
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1
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The absolute limits of photosynthesis [closed]
I have found that some crops, like sugarcane, have a photosynthetic efficiency of 12%. Using extensive genetic modification and eliminating all natural barriers, like light wavelength, chloroplast ...
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2
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Would a human-powered small mecha by using a mechanical lever system and Basic Hydraulics/Hydrostatic Transmission be physically possible?
Well, of course, I know that the question in the title is a bit too brand for the site, but will simplify it down the text so I hope it is more specific to answer. And yes, I know that histories don't ...
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1
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Performance Comparison of Some Common Sci-Fi Propulsion Systems
Want to share some performance comparison I've done recently.
How does a torch ship compare in interplanetary travel to a reactionless drive? How does a reactionless drive compare to a boost drive?
...
- 18.7k
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1
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How Tall Can Flightless Birds Plausibly Get?
These flightless birds are under strong selective pressure to be able to feed on high up conifer needles, and avoid predation from T-Rex sized predatory flightless birds. The forests the birds are ...
- 2,398
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3
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Could black holes be used as a particle accelerator
I was originally was thinking of using the Jets emitted by black holes to create antimatter, however those might not fit the setting I want, due to the fact they are don't seem to occur commonly in ...
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3
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Are Mass Effect "style" guns possible?
In Sci Fi, the majority of weapons come in the form of either some kind of energy beam/bolt, or as testosterone-dripping slug-throwers. In Mass Effect and the Aldreaverse utilize weapons that fire ...
- 4,373
6
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1
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Exoplanet sky with suspended ice crystals
I'm envisioning a planet around a sunlike star, with gravity and temperature similar to Mars, but covered with a thin shell of water ice (with CO2 ice at the poles). The atmosphere's pressure and ...
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Can Mars disintegrate entirely in this scenario?
I have a hypothetical scenario in which Mars flies over Jupiter at close range. I want to make Mars disintegrate entirely in this scenario while keeping the scenario scientifically accurate (please ...
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1
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Can kinetic energy be converted into cooling?
In a hypothetical scenario, I'm trying to design an object where, the faster it moves, the more it cools something it comes into contact with it.
There's all kinds of materials that can convert energy ...
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13
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What would a spacefaring race use as fuel for their matter-to-energy reactors?
Imagine that we invent the technology to convert matter directly to energy, and capture most of the output for doing work. We can convert any matter to energy in this way, i.e. the matter does not ...
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1
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What Would Be The Consequences of An Asteroid Literally Falling Onto An Ice Sheet?
On this alternate Last Glacial Maximum Earth powerful psychics bring an asteroid into near earth orbit and deorbit it using entirely laser ablation. Bringing it carefully down onto the Laurentide Ice ...
- 2,398
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1
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The immediate and long term effects of slashing wounds in microgravity
What would be the specific long term and short term outcomes of slashing wounds in microgravity?
The scenario is that a normal adult is slashed with a knife in a microgravity environment. Assume ...
- 2,421
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Could non-avian dinosaurs survive if introduced into modern world? [duplicate]
Lets say Jurassic park somehow came to existence and someone cloned dinosaurs genetically identical to ones of the past and tried to keep them in a zoo. Could the dinosaurs survive as is?
I'm ...
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Could a tether be used to boost Phobos’s orbit?
Background:
Phobos, the innermost moon of Mars, is in a decaying orbit which will either crash into Mars or break up in a few million years. It is a very valuable staging port in my universe, due to ...
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2
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How would a sky with extreme kessler syndome look like?
A few decades ago the Third World War destroyed Earth. Space infrastructure was considered a priority target by both sides. Orbital space was in the years before the war was filled with skyhooks, ...
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1
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Optimal Fuel for GyroJet Handheld Weapon? [closed]
Is there optimal fuel for gyrojet weapons?
Specifically, what fuel would best propel gyrojets from a hand held launcher (read gun -- ex: pistol, rifle, volley gun, etc.)? I'm looking for velocity -- ...
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1
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What alternate propellants could be used for firearms? [closed]
What propellants could be used to increase the damage or injury caused by firearms?
Answers may include propellants that decrease the service life of the weapon (the weapon should be able to fire a ...
- 2,421
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5
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Is it possible to build a transmitter small enough to fit inside of a .45 caliber bullet?
Is it possible to build a transmitter inside of working .45 caliber bullet?
Specifications:
The bullet must be fireable from a .45 semi-automatic pistol
Transmitter must function after firing
...
- 2,421
4
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2
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How large must a solar furnace be in order to sweep a planets surface melting everything in its path?
To melt a planets surface erasing all traces of civilisation, I figured a solar furnace would do the trick. It is more elegant than nuking a planet, not to mention leaves no nuclear fallout. Perfect ...
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Industrial scale Tritium production from Helium3?
Currently Tritium is produced by neutron bombardment of Lithium. I was looking into alternatives and learned that Helium3 has a rather large cross section for reacting with thermal neutrons. From what ...
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1
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Can a button cell battery power car cigarette lighter (in the shape of a ring)?
Is it possible to make a fake golden ring which can light a candle on the push of a button and power it with button cell battery (either coin cell or watch button size)?
I have a fraud guy trying to ...
- 1,034
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2
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How to make a pump for lots of molten lead?
If I had a steady and powerful wind source and wanted to run a continuous flow of liquid lead, what method would work best to lift the fluid?
One benefit of this fluid is that the machinery will be ...
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6
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Where could you store the energy from a tornado?
Assuming a very large device was constructed which could harvest up to 20% of the mechanical energy of a tornado. It is a mobile platform of some sort, and one or several of these are ready to deploy ...
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1
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How to "miraculously" light any candle? By chemical or technological means
There is a Mystery Busters team that is solving mysteries and catching criminals (like Scooby Gang from Scooby Doo). There is no magic in the setting, the solution is always mundane, a trick done with ...
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1
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Major moon on a geosynchronous orbit of a planet (20 hours)
So, here are the characteristics of the planet:
1.14 times earth radius.
1.16 times earth mass.
rotational period of 20 hours.
it orbits a star of 1.1 solar masses at 1.02 AU.
I want to know if it ...
3
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3
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Zero propellant interplanetary travel [closed]
I am creating a world where there is an interplanetary network that allows planetary commuting to and from all planets and major moons in the solar system with 0 propulsion being supplied by the craft ...
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5
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Igniting a biological H$_2$ fueled pulse jet engine?
A squid-like organism uses gravity powered flight but relies on jet propulsion for launch, pouncing, and evasive tactics.
It’s aerodynamically based on the way a true squid flies however it has ...
- 8,159
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1
answer
93
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Short and long term effects of an Earth sized planet entering Earth's orbit [closed]
In this scenario a Earth analog planet is accidentally pulled into Earth's orbit through the creation of a wormhole. The planet would orbit Earth at about 80,000 miles (128747.52 Km). The planet has ...
2
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5
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What will be the best battery solution for keeping electrical power a tradable commodity in an industrialized star system?
On Earth, electricity became a tradable commodity thanks to Chile in the 1980s, it has since become a staple of international economic markets. One would assume the same outcome to happen on the ...
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3
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How would a futuristic robot soldier look like? [closed]
I feel that whenever I search for something like “futuristic robot soldier”, the results are always similar and they look like designs and concepts made by ARTISTS, not ENGINEERS. As far as I know, ...
5
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1
answer
113
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How to make terrestrial biochemistry more acid-resistant?
So, I'm designing a race of sapient extraterrestrials for a series of short stories, and I've gotten to the point of designing their basic biochemistry, but I have a problem: Both their environment ...
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2
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How to replace glucose with ethanol?
So, I'm designing a species of sapient extraterrestrials for a series of short stories, and I've gotten to the point of needing to find a significant biochemical difference between life on their world ...
- 1,495
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4
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How can my character cool her tea quickly? [closed]
Let's say I have a character that is obsessed with drinking warm tea (or cider, or...).
Tea needs to be steeped at a high temperature; say, 90°c. However, drinking it at that temperature will result ...
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1
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Muzzle velocity of a metallic hydrogen firearm
Related and linked to Metallic Hydrogen Propellant and Barrel length of a metallic hydrogen firearm.
In the two previous questions, I've explored different properties of a firearm that uses metallic ...
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5
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What are some hypothetical specs for Elon Musk's next generation Starship for 2060?
Elon Musk's Starship, formerly known as the BFR (then the ITS), is planned to be the workhorse to transport people and goods to Mars. Theoretically, the rocket could be ready for orbital testing ...
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1
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Barrel length of a metallic hydrogen firearm
A overdue follow up for the question Metallic Hydrogen Propellant.
One of the points that was brought up on the post was that since the gas propelling the bullet would be atomic hydrogen, the ...
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13
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4
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How Big Can An Ancient Bird Powered Glider Get?
What are the practical limitations of a glider made of bronze age materials and pulled by well trained birds?
Due to psychics able to control animals, and a cultural fixation with domestication, ...
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5
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How much gunpowder (or other materials) it would be required to accelerate 4mm Tungsten Sphere to 50 km/s? [closed]
I don't understand much about physics and ballistics, so I hope I don't make too many incorrect assumptions here.
So, I just saw this video where a 4 mm tungsten sphere hits a 85 mm steel armor, and ...
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1
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Would These Three Actions Allow the Ecoregions to Regrow?
This scenario begins with multitudes of vanishings from around the world, at the same time. All of the domesticated animals (dog, goat, pig, sheep, European cattle, zebu, cat, chicken, Guinea pig, ...
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5
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Could a active rotational bullet increase accuracy?
I don't know where I should ask this, on History, Aerodynamics, Physics or here. But here we go.
So, from what I could see on youtube videos (not the best source, I know), the bullets on rifles and ...
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2
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Please Check My Fictional Calculus (Halting Problem, Incompleteness)
For a story, I'm having a character invent a new kind of calculus.
Halting Problem
The new math efficiently solves the Halting Problem.
What is the Halting Problem?
Provided you have code like this --
...
- 18.7k
3
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3
answers
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Can a new geological material (specifically, a metal) be formed no older than 56 million years ago?
There is an alternate Earth that I've been building and rebuilding for years. The canonized point of departure is 56 million years ago, specifically a Paleocene-Eocene Thermal Maximum that is four to ...
- 14.5k
3
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2
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Would a locomotive on ice (like in The Polar Express) move?
In the Polar Express film, there is a scene where the Polar Express runs off the tracks onto a frozen-over lake, which supports it and doesn't collapse even after the locomotive tilting and hitting ...
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1
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Designing A Ring World For A Science-Fantasy Setting
Why Am I Doing This To Myself?
Because I'm designing a surreal pulp science-fantasy tabletop roleplaying game, and I want to take the coolest elements of hard sci-fi and mix it with the punchiness of ...
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2
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Help Fix My Space Elevator - Untapered Steel Cable
I think I have made a mistake somewhere in my design of an untapered steel cable space elevator down to Earth. I was building this as a design reference to figure out how much stronger "stronger&...
- 18.7k
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1
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Is a fall into a high-pressure atmosphere survivable?
In my question What is the largest achievable oxygen-atmosphere world?, my answer suggests an atmosphere of standard terrestrial air with a sea-level pressure of 20 ATM and platforms at an altitude ...
- 55.5k
4
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1
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Hard Science Superhumans [closed]
For my story, I want to create a group of superhumans- to be clear, not humanns with powers, but just humans who have been bioengineered beyond normal human capabilities. This can be something with ...
- 215