Questions tagged [physics]

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

6
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6answers
1k views

How might a purely mechanical 'voice' function?

In my world there are mechanical semi-humanoid automata. Would it be possible to make them speak in a fashion that sounds natural (i.e. human)? How might it function? The mechanism should be capable ...
9
votes
4answers
3k views

How fast can a ship with rotating habitats be accelerated?

Alright so I'm not really a physics person by any stretch so forgive me if I butcher some physics jargon on this post. So I'm making this hard sci-fi interstellar ship with a rotating habitat that ...
9
votes
3answers
109 views

Power of flight vs weight of object in free fall

In my story there are people with super powers, but they only get to have one. So, if someone’s power is to start a fire, then they can’t also control it once it starts. My problem currently is with ...
5
votes
6answers
333 views

Closed off habitat surrounded by extreme heat, is it impossible in the long term without handwavium?

High-tech Ents foresee a calamity befalling their beloved and treasured green planet. Surface temperatures will rise well above 500 Celsius (arbitrary, basically just very hot) for thousands of years, ...
4
votes
1answer
113 views

What construction and physics implications would there be for life in an underwater “high rise building?” [on hold]

I'm working on a project in which part of the story takes place on a planet that is mostly ocean. There is a small continent with some manufacturing and refinery structures, but the rest of the planet'...
0
votes
0answers
105 views

Possible FTL travel methods for hard(ish) sci-fi? [on hold]

I'm working on a story that requires travel at about convenient* speeds (see below). I want to keep this story as hard sci-fi as possible and I've heard about stuff like Alcubierre drives which sound ...
-1
votes
0answers
101 views

What would happen if Superman swung a sword at max speed? [on hold]

What would happen if Superman swung a sword at max speed? Assuming it only hits air would the hilt just separate from the sword, would the sword disintegrate due to the extreme speed it is subjected ...
5
votes
1answer
314 views

Diamagnetism for telekinesis?

My previous/first post on here was to brainstorm a means of telekinesis and pyrokinesis (even if very limited) that violates physics the least. Now I do realize that a lot of handwaving and number-...
-4
votes
3answers
69 views

Perpetuum Mobile [on hold]

Every body knows, that according to Newton's law, isolated vacuum-flask won't spontaneously overheat. Solar-powered machinery would seem sci-fiction in the early times of industrial machinery, now it ...
2
votes
5answers
1k views

Explanation behind shape shifting

I’m writing a novella for a school competition. My main character is a shape shifter. I am trying to find a plausible scientific explanation for how shape shifting is possible. I tried finding ...
9
votes
1answer
210 views

How to build the Cube Prison from Cabin in the Woods?

This question is about the Cube Prison as seen in the 2012 film The Cabin in the Woods. My question is not about the film or its lore, but how the cube prison can be constructed. Specifically, how ...
4
votes
0answers
95 views

What would need to be different from Earth in order to make mecha a viable aspect of warfare on a planet? [closed]

There are lots of great questions and answers on this site about how and why bipedal mecha are near useless on earth, and why spiderlike mecha could perhaps have some niche uses which are unlikely to ...
5
votes
4answers
303 views

Can spiky arm guards/bracer be an alternative weapon for blunt attack or will wielder get broken bones upon hitting?

Basically what's in the title: If someone uses a spiky arm guard/bracer (long bracelet type armor not gauntlet) while bashing/battering an opponent (with or without armor) would this result in the ...
1
vote
1answer
69 views

What would life be like on a habitable, non tidally locked planet around a red dwarf? [closed]

A significant portion of one of my stories is planned to take place on Luyten B - https://en.m.wikipedia.org/wiki/Luyten_b - a potentially habitable exoplanet not far from the Sun. This is a rocky ...
7
votes
3answers
744 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, ...
-3
votes
0answers
91 views

what is a negative charge and how is it made [closed]

When I state negative charge I mean a negative charge that you will find in electrons, please explain it in simple terms when possible to allow a better understanding of what you mean as I have not ...
-2
votes
0answers
69 views

Can positive lighting and negative electricity be two separate elements [closed]

So I tried to find the opposite of lightning that wasn't already in my list (I'm not gonna list that as it is not necessary for the question)so then I wondered if I could just split lightning in two ...
34
votes
0answers
1k views

How soon can the first stars form?

Introduction In our universe, the cosmic microwave background was formed approximately 400,000 years after the Big Bang. It was hot, but within a few million years after the Big Bang, it would no ...
-4
votes
6answers
387 views

Can medieval weapons (swords, spears, polehammers, etc) be more viable than guns in this SciFi setting?

Context In this world, laws of physics are roughly the same as ours. No placeholder magic involved. Wars are fought by cyborgs/mutants/synthetic mutants (super soldiers) who can manipulate certain ...
3
votes
4answers
2k views

What if two planets orbited each other and also a star?

Say another Earth orbited the Earth, instead of the Moon. What effects would that have? Would gravity change in relation to the planets slightly during their orbits? I am world building and am trying ...
68
votes
10answers
10k views

How can powerful telekinesis avoid violating Newton's 3rd Law?

Characters with powerful telekinesis are portrayed as being able to exert a superhuman force using only their minds. For example, they can throw a car. Based on what I remember from high school ...
19
votes
2answers
2k views

What would the consequences be of a high number of solar systems being within close proximity to one another?

What would the consequences be of a high number of solar systems being within close proximity to one another? I'm mainly interested in the consequences for life on multiple planets. When I say 'close ...
8
votes
13answers
5k views

What could cause sudden localized atmospheric pressure change?

Picture a band of happy campers, literal campers, sitting around some fires. Suddenly they feel their inner-ear "filling up" and after mere instants the ears begin popping, as if they were inside a ...
82
votes
19answers
18k views

Would a 'World Tree' be feasible in real life?

A livescience.com article claims that trees can reach a theoretical height of 400 to 426 feet (122 to 130m). This is due to the tree being unable to carry water up to the top at that certain point due ...
3
votes
3answers
198 views

What is the speed limit on nano-construction?

How fast can nanites work Tangential to the above question. This is for a novel about a somewhat near future. The conceit is that very advanced nanites, plus computers that are able to read our minds,...
15
votes
5answers
3k views

How could a civilization detect tachyons?

In an effort to work out a believable form of faster-than-light communications for my setting, I've ruled out a few things: wormholes (which are in use, but are too random in where they lead, to be ...
5
votes
1answer
294 views

How would our skies look if our sun was a white dwarf instead?

What I'm using your information for: My planet is small, has a thicker atmosphere than earth and it's orbiting a white dwarf. The main reason I chose it to be a white dwarf is that I read somewhere ...
14
votes
5answers
2k views

Could the Missouri River be running while Lake Michigan was frozen several meters deep?

During an ice age, would it be possible for a great lake to be frozen while a relatively nearby river was still running? To help illustrate my point: Would it be possible for Lake Michigan (or parts ...
3
votes
3answers
304 views

Ballistics of a 19.25mm revolver

A lead off from my last question, the actual ballistics of the round. I've learned from the last question and ran some numbers and come up with a basic idea for the ballistics of the revolver. Lead ...
5
votes
7answers
399 views

Feasibility of extraterrestrial metals?

In a sci-fi universe where man has the capability to leave our solar system would metals or alloys above and beyond our own be possible? Or at least within the bounds of reasonable possibility? As the ...
6
votes
7answers
773 views

Compact Mechanical Energy Source

In my late-Victorian world there are independently moving automata that may act as pets or servants to those that can afford them. They require a fair amount of energy to run at full capacity, enough ...
5
votes
2answers
297 views

Can an object change its own mass?

I was wondering if an object that changes its own mass could exist. But let's try not to fill it up with air or other gas so it feels "lighter". That way you could protect things from being stolen if ...
7
votes
1answer
171 views

How much energy can I produce per kg of hydrogen using this process?

In the far future the posthuman successors of mankind have disassembled the stars and live on ultra slow and ultra efficient solar system sized computers, Matrioshka Brains. The last enemy of ...
4
votes
3answers
121 views

Incapacitating an android in magnetized liquid oxygen?

A space opera sultan has a problem. Sentient androids are haram, but an unwelcome android spy has saved his life and helped prevent a coup. Rather than have the android destroyed as his ministers ...
25
votes
7answers
7k views

Could a 19.25mm revolver actually exist?

I'm working on writing a story wherein there is a revolver inspired by Guillermo del Toro's Hellboy's samaritan. My question is; can such a gun, as described below, work? Or would it be a bone breaker ...
1
vote
0answers
68 views

what effect if the world have a single massive world giant tree? [closed]

you know stuff like ygdrasil tree but just a normal tree but the biggest and tallest in the world, i wonder what the effect to the world ? for an example if the root grow to surpass the continental ...
29
votes
8answers
6k 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 ...
4
votes
2answers
128 views

What would be the best way for a supernatural entity to fit into a physical body smaller in mass and volume?

Angels are advanced technological beings who are messengers of the gods. These extra-dimensional beings are large, upwards of 30ft tall, and resemble eldritch abominations in their true form, such as ...
7
votes
3answers
136 views

Rotation, weight and planet size

Wouldn't it be cool if giant monsters were on giant planets? Of course it would be, but unfortunately physics doesn't really like that idea. Big planets make things on them need more support, so being ...
5
votes
5answers
541 views

What is the lower bound for lightspeed?

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 ...
1
vote
3answers
221 views

Biggest possible Steampunk Airship? [duplicate]

I have noticed that one thing that is very common among steampunk airship art is that the size of the decks beneath the gas chamber is outrageously larger than that of the real world. Example: ...
2
votes
2answers
300 views

What is the upper bound for Lightspeed? [closed]

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 ...
1
vote
4answers
425 views

Newton's 3rd law & Quantum entanglement

Once a long long time ago a guy called Newton came up with a law he called his 3rd law. "The laws of motion" Everyone knows about "Every action has an equal and opposite reaction" My question here ...
20
votes
5answers
3k views

How would a physicist explain this starship engine?

In my world, interstellar vessels use a drive whose design mankind learned from an extinct elder civilization. While construction of the drives is possible, the physical principles making them work ...
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 ...
10
votes
3answers
460 views

Can I render satellite deployment impossible, or at least impractical, by exploiting the Kessler syndrome?

I want to render impractical the deployment of satellites by exploiting the Kessler syndrome. Why, you ask? Maybe I'm an evil overlord and I don't want those pesky satellites flying over my lair. ...
10
votes
1answer
147 views

Using sound to swim through sand

Subarenaceous animals are those which can move long distances through dry sand - like sandfish lizards, or Dune's sandworms. The main problem they have to tackle is turning the sand immediately around ...
3
votes
3answers
273 views

Are there any issues with this FTL drive concept?

I asked a question earlier on here concerning Negative and Heavy Matter - hypothetical types of matter I created to have a working FTL drive. With some extra work, I’ve tweaked the concept and been ...
20
votes
10answers
5k views

Could there be a material that inverts the colours seen through it?

I had a vision of a creature that touched things, and wherever it touched, it left a mark opposite to the original colour. For example when it walked across the grass the grass had red footprints, ...
3
votes
5answers
238 views

Actual ramifications of time acceleration

For reference, the setting is urban fantasy, with a bit of hard science thrown in. One character can manipulate time; in this setting that means he can speed up his own movement through time. One of ...