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For questions regarding the physics relevant to fictitious worlds. General physics may be off-topic.

3
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1answer
40 views

How many dead bodies are required to stain a river red?

Historical accounts of battles sometimes talk of rivers running red with the blood of fallen combatants. Many Lancastrians were killed while fleeing; some trampled each other and others drowned in ...
1
vote
2answers
141 views

How could a medieval society catch a large number of birds in a short length of time?

I was lounging about in my throne room when a man came to speak to me. He had one leg cut off (recently, too) and claimed he was an alchemist. He says that he wants to get revenge on the king of the ...
8
votes
3answers
1k views

How fast would a Martian space elevator travel?

READ EDITS I am writing a passage about the main character of my book travelling up a space elevator to the spaceport that rests in geostationary orbit above Mars. This means that the elevator would ...
4
votes
4answers
91 views

Applications of Electromagnetism in “Force Fields”

Lengthy Explanation of Why I'm Here: TLDR; "force field" made of electromagnetic radiation. Recently, I've decided to compile a list of possible technologies available in the 22nd and 23rd centuries,...
2
votes
3answers
131 views

Making a 180 degree turn around a star

For a book under construction, I need a starship to make a 180 degree turn rather quickly. Give him sub-light speed in a star system (no relativistic effects) and on a path to the system primary. I ...
0
votes
2answers
71 views

Storing 200TJ of Electricity for rapid discharge

Here's the problem I'm having. I need a solution for the following situation. I have a sci-fi starship drive that needs 140TJ of energy every 6 hours. I have a Fusion Reactor that can produce 200TJ ...
1
vote
1answer
62 views

Controlling Physical States By Changing Molecule Density

I'm developing a world where certain people have affinity to modify/control certain aspects of the material plane. In the early stages I'd included the good old "element control" premise, but as I ...
3
votes
2answers
83 views

Batteries and resource restrictions

I've prefigured a specific setting as being middling in technological progress when compared with its neighbors. This setting does not have access to hydrocarbons, has severe cultural and political ...
1
vote
1answer
90 views

How big does a moon have to be to have the earth locked to it?

I would like a earth-moon system like Pluto-Charon (but with earth instead of Pluto) where both will be tidally locked to each other within something like 3 billion years (before complex life appears)....
7
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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 ...
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 ...
1
vote
1answer
90 views

Building a planet with a primordial black hole core

I have been trying to figure out a way of explaining how an advanced society some time in the past built an artificial planet with a black hole at its core and the effects that would have on the ...
12
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4answers
2k views

Simulating gravity in a gravity-less universe

In my fantasy universe, there is a disc-shaped world that has a flat surface that has roughly the same atmosphere as Earth (see this); the atmosphere moves along with the world. There is no gravity in ...
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votes
3answers
167 views

Full body bullet resistant armour

The "people" wearing this are 10 times stronger than humans and have near unlimited muscular endurance so weight is of little (but not no) concern. Their ballistic and gun technology is as advanced ...
1
vote
2answers
153 views

Would the Earth with 4 moons still be habitable?

I'm currently writing about an Earth sized planet that is 33% water and has 4 moons all the same size as our moon. All moons are 243,000 miles from the planet's surface and the planet takes 392 days ...
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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 ...
1
vote
4answers
199 views

How tall do atmosphere retaining walls on rotating space habitats need to be?

A common, matter-efficient science-fiction habitat is a hollow cylinder or ring in space that is spun to simulate the pull of gravity on its interior surface. These habitats have been imagined as ...
3
votes
3answers
154 views

Life and technology in magnetically-floating islands [closed]

I'm designing a world that has a series of layered floating islands, that are kept aloft due to magnetism. What sort of secondary effects might occur with a planetary magnetic field strong enough to ...
46
votes
26answers
12k views

If a large space ship crashes on a planet, what could kill passengers without obliterating the ship?

The situation I'm considering is as follows: A large research vessel with a crew of about 100-200 attempts to land on a potentially habitable planet, but something goes wrong during the descent. A ...
2
votes
5answers
218 views

How to integrate magic with nature, avoid the “our world with magic tacked on” problem? [closed]

tl;dr The typical fantasy setting is just Earth with "magic" tacked on to let the wizards cheat nature. There is absolutely no attempt to integrate magic with nature. Trees, lightning, birds and so ...
0
votes
1answer
96 views

Possibility of a dyson sphere-esque structure with earth physics? [duplicate]

I have an idea for a DS-like world setting mostly set after the year 4200. The Earth was destroyed around 2500 and humanity moved from earth to an asteroid best and built a giant dyson sphere to live ...
11
votes
4answers
249 views

Wading through high-inertia particulates: how could pre-modern technology best approximate a protective, slick, waterproof suit?

In the supernatural plane of existence known as The Exhibition, time appears frozen - nothing is moving, falling objects are suspended motionless, the works. In addition to this, while outside ...
10
votes
3answers
197 views

Feasibility of floating city-sized forests

My world is essentially a Neptune-sized gas planet that got seeded with life and its surface layer filled with oxygen, therefore gaining a sizeable layer with Earthlike conditions. Within this layer,...
7
votes
5answers
221 views

What required secondary powers does my speedster need in order to be able to accelerate at 2,250 ft/s^2 without harmful effects?

This question was originally posted in the Sandbox. It's set in the same world as this question, but is not related to it. I have a speedster character whose top speed is Mach 2. She holds back a lot ...
5
votes
1answer
174 views

Energy cost of creating body parts from nothing but energy

What amount of energy would you need to expend to create an arm out of nothing but energy? Of course we have $E = m c^2$ telling us the energy any amount of mass represents. Given the average of a ...
10
votes
2answers
2k views

How would a corpse be preserved in outer space conditions?

Suppose you were puttering around the solar system and came across the remains of a luxury passenger vessel, the intergalactic equivalent of the Titanic, adrift about one AU from the sun. The hull was ...
4
votes
4answers
116 views

Changing Earth's axis suddenly or gradually?

First post, if it isn't completely obvious. I've discovered this site by trying to "google" that question. Here's what I'm investigating: Long ago, pre-deluvian civilizations built ancient megalithic ...
3
votes
4answers
281 views

VERY dense asteroid belt - possible?

I'm making a game which takes place in an asteroid field that is very dense - I'm talking close enough that one is able to jump between asteroids (provided you have some sort of additional thrust ...
0
votes
1answer
60 views

Voodoo via particle entanglement

In a world where science has advanced to the point of a healthy understanding of particle physics, scientists have begun working towards remote matter manipulation. In theory, it seems that one would ...
37
votes
9answers
11k views

What are the effects of slicing the Earth in half with a particle beam?

Scenario: An exact copy of our world is sliced in half by a particle beam. The beam has a diameter of 40 meters and moves at a speed of 0.999c. The beam slices the earth from top to bottom in 600 ...
13
votes
5answers
4k views

Would everything be miniature on a miniature Earth?

If there was a planet half the earth’s diameter, for which every other aspect of the earth was changed proportionally to keep the Earth’s perfect ratio intact (including having the perfect orbital ...
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votes
2answers
101 views

What happens to an object when it passes through a portal? [closed]

As in the game Portal, if we create two portals on two different surfaces and then join the two surfaces with the portals facing each other, as soon as an object passes through one of them, what would ...
4
votes
4answers
125 views

Could charged plasma be used as a working fluid to spin a magnetic turbine to generate electricity?

As the title suggests, this is a conceptual physics kinda question. What is the feasibility of using an electrically charged (as in not neutral) plasma as the working fluid in a turbine where the ...
23
votes
16answers
10k views

What happens when a moving vehicle loses all its kinetic energy at once

In the system of magic that I am using I try to follow the laws of physics as much as possible. The idea being that whatever magic can do, a scientist and machine can eventually do. One of the things ...
2
votes
2answers
173 views

Would a planet with these seasons be possible?

Just as a disclaimer, I have very little knowledge on the science on all of this and have a very poor grasp on what is plausible and what isn't, but I suppose that's why I am here. I have a concept ...
7
votes
2answers
513 views

Siamese Twin Planets?

Premise I want to explore the possibility of a planet that is extremely misshapen. If we were to extrapolate what we have observed from our solar system and the extra-solar planets discovered so far, ...
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votes
1answer
227 views

Firing an AK-47 while anchored to the ISS [closed]

The Setup I magnetically anchor myself to the floor of the ISS. (yes I know there's no "floor", any wall will do) Then, I fire a 5-round burst out the airlock. The Question Can the recoil from ...
10
votes
4answers
2k views

Could a world exist with a distinct line of changing temperatures between the hemispheres?

I'm trying to create a world where there's an equator-like divide running along the axis(?) of the planet and the two hemispheres are perpetually different in terms of temperature. Basically, I want ...
2
votes
2answers
163 views

How much energy would be required to vaporise a giant reptilian monster?

At the climax of my story, the main antagonist transforms into a gigantic and nigh-unkillable monstrosity that resembles an unholy hybrid of a crocodile, Mosasaurus and Dimetrodon. After a long and ...
10
votes
6answers
290 views

Do moons determine the speeds at which tides move? Is there a limit to this speed?

I'm writing a short story that takes place on an imaginary planet that is 88% ocean. The planet has two moons and one continent that is regularly flooded under 500 to 1500 feet of water. The tides are ...
10
votes
3answers
2k views

Could excessive fracking over long periods of time cause tectonic plates to shift significantly?

Trying to create a future earth which has been thoroughly abused by the excesses of modern capitalism. Extreme weather, rising sea levels, massive droughts, that sort of stuff. My question is: ...
1
vote
5answers
161 views

What mechanism could be used to create an eternal night?

My question is how a species, given sufficiently advanced technology - could block out all - or most - visible light to a generally earthlike planet without rendering it uninhabitable. The only ...
6
votes
1answer
274 views

I've determined how many planets my solar system could plausibly have. How do I figure out what kind of planets they are?

The 12 planets in my solar system orbit the G-type star of Nemo. It's about nine-tenths of the size of the sun, and has a stellar luminosity of 0.67 L☉, a diameter of 1.28 million kilometres, a ...
6
votes
4answers
308 views

Are there size constraints to Time Bubbles?

I'm creating various artificial Time Bubbles in my universe where time flows faster or slower inside a specified area, typically depicted as a semi-transparent bubble. Before developing any more ...
6
votes
4answers
219 views

Would my lizardmen be good at throwing things?

Okay, so I was creating a cold-blooded humanoid species (for a story, I'm no scientist) and ran into a problem with some of my logic. Because of their obvious issues with overheating, these ...
7
votes
2answers
233 views

Could I put a large city into geostationary orbit?

I want to put a circular city in geostationary orbit. The city will have a radius of 20Km. I was thinking of using quantum trapping/levitation to achieve this. Here's what quantum trapping is: ...
2
votes
6answers
259 views

Protection against h-bomb core explosion conditions thinkable?

Assume a human in direct vicinity (think 1-50 m [if you need more space for your intended device]) to the explosion center of a nuclear fusion bomb. Is survival via technology thinkable? The TNT ...
18
votes
12answers
5k views

In a spinning Dyson ring, would objects not touching the surface experience gravity?

I have a world inside a Dyson ring with a radius of ~1 AU, complete with humans, animals, plants, clouds, and Earth-like atmosphere. The ring is spinning at a particular angular speed, giving the ...
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votes
2answers
149 views

What would happen if an object traveling faster-than-light, with negative mass, crashed into something moving at sub-light speeds? [closed]

The warp drives I have defined for my science fiction setting work by creating a field which gives the ship a net negative mass to allow for faster-than-light travel. What I want to know is how an ...
27
votes
9answers
5k views

Sailing without wind, but with strong currents

Context On my world, there is a lot of water: sea, oceans, ... There are also firm land and islands, so it's interesting to travel on the water. The problem is that there is NO wind at all, and lots ...