Questions tagged [paradox]
For questions in which an event, object, or idea contradicts itself, defying logic.
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If time travel is possible in the future, no matter how distant, why haven't they come back to tell us?
In a world where time travel is possible, but has not been invented yet, would travelers from the future come back to prove it exists?
Surely, they would bring that technology back in time to let the ...
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A solution for the time-travel paradox - What could go wrong?
Time travel has been invented and it goes like this.
You travel backwards in time at the same speed you normally travel forward. Everything is identical - you do all the actions the same but in ...
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What to bring back from the past to prove the success of a Time Machine? [closed]
Reference this thread for more on the putative time machine.
So my intrepid time travelers set out in their DC-3 in late September 1962, not really knowing where they are going or how to get back. ...
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Avoiding preventing your own birth in a time travel paradox?
Assume a world with no multiverse theory, just a single unbroken timeline. If you were to go back in time to the town your parents lived in on day of your conception, the air displacement due to your ...
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How do you prevent causal loops from happening with the Novikov self-consistency principle?
The Novikov self-consistency principle states that all changes that occur due to time travel into the past were always part of history, and so the course of events is not changed. While this is useful ...
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Does this time travel delivery service cause paradoxes, and if so how can I avoid them?
After the time travel designs from the CASH WHEN YOU NEED IT YESTERDAY business was stolen by a corporate spy, Amazon now has time travel capabilities. Of course, saying that they could deliver the ...
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Bootstrap paradox with a time machine in iron
I wonder if a time machine can be the cause of a bootstrap paradox?
Background: Let's say one day I found in my room a portable time machine. I use this machine to travel to the future, where I ...
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In a world with time travel, would it be possible to be your own mother's mother?
Given that you can travel back in time and have a baby there, or alternatively, send your baby back in time, would it be possible that this baby one day becomes your own mother (gives birth to you)? ...
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Addressing paradoxes with Weapons designed to hit a target in the past
In space, normal weapons are so easy to dodge because by the time you see an enemy ship and fire at it, it's already moved out of the way. Now imagine a weapon that travels backwards in
time as it ...
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What would two people reading each other's mind think? [closed]
Imagine that two people who have the ability to read anyone's mind confront each other. Each one of them knows that the other is able to read minds and so they try to read each other's mind.
Let's ...
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Paradox Free Time Travel: What Are the Implications of the “One More Ball” Thought Experiment? [closed]
Note: this question uses third-party worlds and events to illustrate
the point, but it is not in any way about them, therefore this
question is not off-topic.
I have had an interest in time travel. ...
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Is the scientific method viable in a world with a god that can and does bend reality by will?
Consider our world at 18-19 centuries. Our civilization knows how to print books, build steam machines, we have made first experiments on electricity. And one day the Mad God Sheogorath is emerged. He ...
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Would time travel to bring someone from the past to the future be possible? Without creating paradoxes or other impediments? [closed]
Assuming we have the technology to travel to the past (about 2 years ago for example). If I replace someone who is in a coma about to die of cancer with a clone (in this hypothetical situation, for ...
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How could a character verify they aren't crazy after accidental time travel [closed]
A 40-year-old character from today (April 2020) with a good memory is unexpectedly transported back in time 30 years. One instant he is at work, the next he is back in grade school in his 10-year-old ...
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Is moving faster than light speed a paradox? [closed]
Let's assume that somehow humanity invented a teleporting machine that could momentarily transport a person over very large distances (up to several light years).
As we know, the speed of light is ...
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Can 'prions' help me avoid a genetic engineering temporal paradox?
On the world of Ruquelis, the horrific practise of cannibalism stands on three legs, however, this question is concerned only with Leg #1: Genetics.
In How to have 'easy' sexual morphs in ...
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A sensible universe for a fictional story [closed]
I wouldn't call this scientifically accurate, but would like some opinion on sensibility of the idea.
As part of a story about two time travelling engineers, they discover that their own universe ...
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How exactly would this chronology protection for my FTL drive look like?
The problem with FTL is that, due to the tachyonic antitelephone, it allows causality violation: I send you a superluminal message (you are moving away from me at relativistic speed), you reply with a ...
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What if we discovered a real paradox? [closed]
On an elementary school in the US, there was a teacher who used to give the pupils math exercises he invented himself. One day, they calculated the cathetus of a right triangle and magically, they got ...
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People moving through time in different directions: Do they run into each other more than once?
This is a question about the relationship between a character moving backward through time and her relationship with characters who move forward through time.
The character [Cate] travels backward ...
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Making an internally consistent, logical set of rules for time travel (based off of this video)
https://youtube.com/watch?v=XayNKY944lY
Something similar to this.
Okay, so the basic plot structure I want is that there are two parallel timelines, both of them potential futures for our world. ...
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I have two cellphones that are exactly the same, SIM card and all, and I make a call on one of them. What happens?
Say I had a cellphone, let's call it cellphone A, and made a perfect copy of it - SIM card and all - and let's call this one cellphone B.
If I were to call someone on cellphone A, what exactly would ...
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This is going to sound insane but… can we eliminate numbers+arithmetic from math? [closed]
This is going to sound insane but... would it not be nice, if there was no need for numbers (except for counting like in subscripts)? Mathematicians talk about eliminating the Axiom of Choice, because ...
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