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Questions tagged [time-travel]

For questions relating to travel in time. Such travel often involves FTL travel; consider also using the [tag:faster-than-light] tag.

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3answers
317 views

Which modern technologies can I use to pass myself off as a God / Demi-god in the medieval era? [closed]

Alex has a time machine. Alex wants to be revered as a god, change human history and make everyone worship him as the reincarnation of said god. I decide to be a god of war and conquer a big part of ...
1
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4answers
263 views

If I travel through a worm hole some massive distance, lets say 6 billion light years, have I traveled in time? [closed]

I'm writing a sci-fi novel and I want it to be well founded in science but I'm a bit confused about time travel vs distance travel. Some have said that to travel great distances is really time travel. ...
30
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10answers
7k views

How do I manage memetic infection while time traveling?

Time travel works...just invented, by you. The tests prove it! After many conversations and significant planning, your epidemiologist significant other has approved your plans for time travel, ...
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2answers
208 views

Effects of an uninvolved time traveller [closed]

This is part one of two related questions. Let us suppose that we have an expert in a a particular period of time, a person who is one of the world's foremost experts on the period. This person also ...
0
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1answer
113 views

Time travel wars [closed]

I am wondering how futuristic wars would play out if time travel was an available technology, sort of like the Time War in Doctor Who. assuming a galactic war where both sides are fairly evenly ...
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4answers
115 views

Motives for preventing a generation ship from reaching its destination - but not destroy it [closed]

The home planet of a race is completely annihilated (hit by another planet or something), but they managed to launch a generation ship beforehand, and a few thousand people go on a century-long trip ...
6
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3answers
3k views

What is the probability of two people having two identical scars? [closed]

What is the probability of two people having the same scar on their body in the same spot and the same shape and the same backstory (drunk driver in a chevy '78) Could the scar be a viable form of ...
1
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5answers
207 views

What can I offer to talented people if I can't allow them to have anything? [closed]

In your not-so-distant future of the 25th century humanity finally found a solution to one of the biggest problems: can we travel back through time? Actually, yes we can. However, there is a big BUT: ...
3
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6answers
294 views

What knowledge or occupation today would be most useful if time-travelling back to the Middle Ages? [closed]

Note: I'm new to this site, and I'm aware that the rules say it's better to ask questions that can answered, not just discussed, so if it is better I could phrase my question this way instead: "Are ...
3
votes
5answers
263 views

Criminal law and backward time travel

Alright, this might sound pretty convoluted, but I would truly value an expert eye to help me with a very theoretical situation. I've been working on a science fiction novel where the whole world ...
16
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15answers
5k views

How to tell someone they have travelled in time, by gesturing?

Two strangers, Alice and Daisuke, are from two different cultures and speak different languages. Oh, and they are from two different times! Alice, was unwillingly, unknowingly and unexpectedly ...
0
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4answers
114 views

Legal consequences of duplicated and “resurrected” people in a Temporal shift [closed]

A plane goes trough some kind of atmospheric disturbance and ends up badly damaged, crashing after trying an emergency landing. Of 200 passengers onboard, only 80 survive, some of them badly injured (...
2
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6answers
242 views

A time travelers impact on history [closed]

Suppose a person from our time is somehow (unintentionally) transferred to Western Europe during the late Middle Ages (circa 1300-1400). In a universe that allows multiple timelines, natural or ...
2
votes
3answers
284 views

Faster time for humans compared to (more advanced) intergalactic civilizations

This is my first post, I apologize in advance if my English is not accurate, it is not my first language. My question is: in a world where very advanced civilizations have achieved intergalactic ...
3
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7answers
1k views

If a character travels back in time … is their demise within reason?

If a character - or a bunch of them - travel back in time to undo a chain of events that would have led to their conception and births, is it within reason that I have them die or 'fade from existence'...
7
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8answers
2k views

Time Traveller's Problem: Is This a Stable Loop? [closed]

I come from Europe, year 2017. One day, I fell through time to 1317. I have no idea how that happened. There must have been some kind of invisible one-way "rabbit hole" in my attic. So here I am, in ...
0
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1answer
273 views

“Time travel” and temperature/energy [closed]

I'm sure people have heard many times of faster forward time-travel, likely involving speed and or gravity, bending the fabric of space-time. But what I would like to know, is if it is realistic to ...
15
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9answers
1k views

Can a modern book that traveled back in time be proven to be older?

Imagine I travel back in time ~500 years, leave a modern ship/boat log book in a cave and the log book was discovered today. Since the book was discovered after it was possible to buy it off the shelf ...
0
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6answers
206 views

What techniques can be used to mitigate obstruction impact during time-travel?

In the future, when an object emerges in a different time, that moment is referred to as a crowning. An impacted crowning is when said object materializes within another object, fusing with it. An ...
2
votes
6answers
354 views

Is there any feasible real sounding science sci-fi explanation for a chronovisor?

What would be able to explain a visor like device that can see the past or future? I'm trying to make it as little as clarketech as possible. Any ideas?
5
votes
4answers
206 views

Is there any Rubber/Latex source that could have been used by Europeans prior to the discovery of the Americas?

I was imagining a scenario where an 21st century engineer accidentally finds himself transported through time to early Renaissance Europe. Realizing that no help or rescue is on the way, he decides to ...
3
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2answers
292 views

Obtaining past winning lottery numbers [closed]

For a science fiction story involving time travel, where the protagonists can go back exactly 33 years from 2013 to 1980, and are looking for a way to make a lot of money quickly: Is there any way ...
6
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3answers
1k views

Can time move faster on another world

What is a plausible way for a planet to have time pass 10× faster than another? Seen the movie Interstellar? That one planet that time ran slower on? It the same idea but the other way around. Is ...
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6answers
180 views

Alternatives to time travel [closed]

Little thought experiment. #GeDANKen A man wishes to travel through time to save the love of his life. Only, he can't. While he can't revisit the past, he discovers a way he might be able to change ...
17
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3answers
4k views

If a person does not age can their hair and nails still grow?

In my story, those who are transported back in time do not age if they have to live through the years in the past. You don't start aging again until you reach the point in time you left. I was ...
20
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8answers
2k views

How to figure out someone is plagiarizing the future? [closed]

In my story, there is a character who can go back in time, and has done so already, for the purpose of getting rich. He is not the main antagonist, neither is he the main character. He is mostly just ...
19
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16answers
2k views

How to not get caught milking the stock market with a time machine

Suppose I have a machine that lets me see the near future, and I want to use this to get rich on the stock market. What is the best way to invest so that no one suspects that I'm doing something ...
1
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6answers
297 views

Prolonging life through vibrating near light speed?

Inspired by this question. Suppose we can get a container strong enough to withstand the force needed for the vibration, and the human or clock within is able to survive the duration of the ...
2
votes
3answers
383 views

How would you build a castle if you went back to medieval ages with current technology — within limits? [closed]

Suppose you are going on a trip back to 1300 Western Europe. You can take supplies with you and a contingent of people to help run things. You can only travel once and your goal is to stay for the ...
11
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4answers
762 views

Time travel and random events

Suppose we have a Branching Timeline paradigm, in which time travel into the past creates a new timeline. Is it fair to assume that any probabalistic events which might occur might be very different ...
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votes
2answers
185 views

Could a modern man live in the past not to betray himself? [closed]

Could a modern man live in the past and not betray himself? How important would immunity, appearance, language, etc. be? What problems would a person from the distant past experience in our world?
1
vote
4answers
378 views

How to convince my parents I am from the future? [duplicate]

Here I am, my today's self transported back to 1981, to the happy and cosy Paris western suburbs of my childhood. I know I will be here for a few hours and the only thing I would like to do is to meet ...
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1answer
150 views

What will happen to an object placed between two portals facing each other

Here's the deal: There are actually four portals. Two of them facing to a black hole and their linked portals are facing each other In image BH is black hole P1 is portal number one similarly P2,P3,...
6
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5answers
665 views

How to realistically build a time machine?

In 1890’s H.G. Wells famously takes a “science fiction” approach to time travel by building a machine that can move freely through time as a dimension. It was made of clockwork — mechanical gears and ...
59
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21answers
7k views

Prehistoric messages to the future

I'm one of the test subjects for a new device, capable of sending an individual back to any point in history. I've been told that - due to certain problems with the process - I'll arrive naked, and so ...
43
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16answers
8k views

Suitable jobs in Ancient Rome for time travelers

The people of Handwave-land have created time travel technology and are training people to send back to Ancient Rome and become part of the community without disturbing the future too much (to observe ...
10
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5answers
563 views

How bad would life have to be to resettle, even if safety is based on hearsay

In the world that I'm building, life on Earth has gotten pretty unbearable for some. My first thoughts are over-population, pollution, war, etc. A company/government comes along and tells you and your ...
0
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3answers
173 views

How to make time travel beneficial? [closed]

I finally found the answer! After hundreds of white-boards filled, I am sure I can build the first time machine! ...Wow, it will be expensive, and time consuming... and actually pointless... Unless, ...
13
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15answers
6k views

How can I make medieval folks addicted to food?

Let’s say I have a time machine and I travel back to medieval Europe. I befriend a girl and she needs my help to save the business of her mother: a restaurant, inn, tavern, etc. I travel back to the ...
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1answer
143 views

What scientific mysteries could be explained by temporal gravity? [closed]

There is a way (somewhat handwaved) in which someone can travel through time. This is not merely the standard one dimension of time, for there are branching timelines. Whenever you travel into the ...
4
votes
8answers
821 views

What minimalistic message from the future would make you most successful? [closed]

I'm a tinkerer, working in my garage on a time machine. I had some success. Saying "I built the time machine" would be too much. I built the receiver. It can provide exactly one bit of information, 0 ...
1
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4answers
198 views

The time travelling Dentist [closed]

A dentist discovers a machine that allows her to travel back in time and go to Europe in 1500 AD. The machine allows her to go back in time only once (and never to return). These are harsh conditions, ...
14
votes
4answers
290 views

Grammatical tenses for time travelers

A staple of time travel stories is a moment where the meaning of “before” or “past” can't be taken in the simple normal way, and everyone laughs at the novelty. In reality, a trained ChronoCop Agent ...
5
votes
6answers
796 views

FTL in a relativistic universe. Am I avoiding the time-machine?

The introduction of FTL travel/communication in a relativistic universe may effectively be equal to having a time-machine with all the problems that may entail for causality. I would like to avoid ...
14
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7answers
3k views

How does a teleporter logically lead to time travel? [closed]

I've read a good number of FTL equals time travel questions and answers both here and on other sites, but for the life of me I just do not get the connection. Let's take a really simple case: say at ...
122
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33answers
23k views

What cheap modern items can I use to bribe medieval people? [closed]

Inspired by this question about a time traveller. So, I've travelled to the medieval age. Think 12th / 13th century Europe. Unlike the time traveller in the other question, I did bring batteries for ...
4
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3answers
446 views

Will This Violate Causality?

Okay, so I have a sci-fi setting in which there is a form of FTL travel. Imagine the universe(all three/four dimensions of it) was stretched out onto the surface of a sphere. Now assume that there ...
5
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5answers
706 views

If an immortal, fabricated particle could travel FTL, would it exist in all times, or only the past relative to its present?

This seemed too scifi or hypothetical for physics, so here goes. Suppose a manipulated quark with 0 mass could travel faster than the speed of light. It's known that the faster you go, the slower ...
6
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3answers
628 views

How to send a message to the past using a precognizant rabbit?

Let's say we have a wild rabbit that can see a few minutes into the future. Being a non-sentient animal, it barely registers these abilities, and largely uses it to find food, avoid predators, save ...
5
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3answers
313 views

How can the more lucky friend of John Doe past-proof his travel to Versailles?

We know the depressing fate of John Doe who woke up one day in the Middle Ages, to quickly die or spend his life in a monastery. His more lucky friend Mark had a vision before being transported and ...