Discussion Time travelling paradoxes

I just want to know some time travelling paradoxes, like if I kill my grandfather, I wouldn't be born which means he was never shot, and stuff like that

Really? Was quite simple to me, though the concept of marrying yourself to give birth to yourself and raise yourself to kill yourself is indeed complex

 

Well there is the good old casual loop, where your actions when going back in time is what caused the events that lead you to go back in time in the first place.

On a side note, most time travel paradoxes only actually apply if you assume it is all in one single timeline, things become very different if you open up for the possibility of many separate timelines existing.

 

I didn't register what you said properly but I believe in the multiverse theory(?) from that one episode in rick and morty So technically there wouldn't be a paradox? Or maybe I'm babbling nonsense

 

It won't be a paradox as paradox arises from contradictions. If we incluse multiverses then there are no contradictions

 

Predestination is a messed up movie about an impossible situation created by time travel—the impossible bootstrap paradox. It's not that the movie's difficult to understand, it's that by the end of it, I wished I didn't understand it.

 

Oh right, my bad it was confusing.

 

One thing that complicates things though is a lot of time travel in fiction isn't actually explicit if it is a single timeline or multiple ones.
There is plenty of times when an apparent paradox can be rationalized as being a case of multiple timelines.

 

Everything you do has already been done including time traveling and whatever you do in whenever time you go to thus creating your current timeline and making anything you do completely irrelevant because you've already done it just not yet

 

Umu, noted.

 

If you don't like the multiverse theory, then you can think that time traveling isn't actually turning the time back, but rather the world turning back. It's not you who went back in time, but the past world came to you. Time was never reversed and whatever you have done will although change the "future" but will never create a paradox since this is the present. The world will continue as it is because time is a concept that humans have created in the first place. This is why every country has its own calender and that is why noone can determine the beginning of the universe.

 

MinutePhysics channel on YouTube made an excellent movie explaining how time travel works in different movies in a short and intuitive manner. The visualization is also easy to understand. You should check it out.

 

I like minute physics haha

I remember polchinski paradox. It is something about a billiard ball that passed through a wormhole to collide with it's earlier/younger version to stop it from going into the wormhole. I don't know much details but it's most based on laws of motion and not restricted by things like free will and stuff.

 

Time travel discussions are quite often inane, because how time travel works depends solely on the imagination of people and people are not of one mind.

 

This is a short film I literally saw after this post:
"A young man searches for his father; the man who'd disappeared on the night of his conception, leaving behind only a ring. His mother names him after his biological father and passes on the ring which he wears religiously. On her deathbed she reveals the truth to him; how the two strangers, at a Masquerade party, became lovers; and the tragic disappearance of his biological father.
The son vows to find his father. Years later, he discovers that his father's ring is made of an element which doesn't exist on earth. He researches relentlessly and makes a break-through: Time-Travel.
So, he travels back in time to the Masquerade Party to meet his father. Unfortunately, everyone is in masks and he is unable to find anyone who knows his father. Disappointed, he drinks heavily and sits dejectedly at the bar. He vaguely remembers seeing a beautiful masked girl, someone he feels he knows intimately, approach him. Her innocent laughter is the last memory he has before he wakes up in her bedroom.
He turns to look at his lover and simultaneously sees his reflection in the mirror while wearing the amulet memento. He is speechless with shock as he realizes that he is his own father and the woman on the bed is his mother in her youth. In confused rage, he throws the ring and disappears forever. "
I couldn't find a good paradox story, but I think this qualifies ;P.

 

How come they are so predictable, these paradoxes

 

They have a template, they just fill the characters and done

 

I feel that the most ignored time travel paradox is that of Harry Potter and the Prisoner of Azkaban. Potter saves himself with his patronus charm.

 

...what?

 

I remember hearing this one somewhere; you go back in time and meet Einstein and explain the theory of general relativity to him (then you go back to the future) he later publishes it and your younger self learns about it in school. Wait, now that I think about it, that should logically only work if Einstein was able to create the theory without your help right? And then your time travel was useless.... eh

 

But it is not a paradox? It's a nice tiny little loop of time that fits together perfectly.