Grandfather Paradox

[GST1441]

This paradox is pretty confusing, or is it? The grandfather paradox simply explains that, if we kill our grandfather(before sex), we would simply live on. But wait, what happens to the grandfather? To me, my hypothesis is the grandfather will disappear and another one will appear. But what happens if we didn't kill him, but instead we killed all his sperm? That means we wont exist, that means a new one will appear right. But to my opinion, no. My hypothesis of what probably will happen is the old grandfather will still be living, but another grandfather will be born into the world. Why? Because the grandfather hasn't died so he won't disappear but he also can't make love to our grandmother so we won't be born. Thus, another grandfather will be born into the world. I'm not sure of my opinions and hypothesis because scientists probably have already explained this but I'm just sharing my opinion.

[ajb]

The grandfather paradox is a rather gruesome thought experiment on the problems with causality and time travel. You can think of less brutal paradoxes and ask if your ideas also solve them. There should be nothing special about your grandfather and his sperm!

Edited February 22, 2015 by ajb

[Strange]

A simpler (and less morally dubious example): you find a book with instructions of how to build a time-machine. The book is unique - the only one in existence. So to make sure it is not found by anyone else, you build a time machine go back in time and burn the book. But that means you couldn't build the time machine and so you couldn't go back and destroy the book. And so the book exists and you could build a time machine ...

 

The same paradox can exist the other way round: you find a book describing how to build a time machine. You build a time machine and take the book back in time and leave it where you will find it. Thus enabling you to build the time machine. But where did the book come from? (This happens in Bill and Ted's Excellent Adventure - Bill and Ted from the future introduce "Rufus" to Bill and Ted in the past; later, that Bill and Ted travel back in time and introduce Rufus to their former selves. But the only way they know Rufus's name is because they told themselves. How did they know what his name was?)

[ajb]

The same paradox can exist the other way round: you find a book describing how to build a time machine. You build a time machine and take the book back in time and leave it where you will find it. Thus enabling you to build the time machine. But where did the book come from?

In physics we call the book a 'jinn'. It seems to have existed forever on a CTC (closed time-like curve). There are are then questions about entropy and how the book just does not get any older.

[Strange]

In physics we call the book a 'jinn'. It seems to have existed forever on a CTC (closed time-like curve). There are are then questions about entropy and how the book just does not get any older.

 

Hmmm.... Interesting it should get older. In some stories, I think this addressed by the character recreating it each time.

[Mad For Science]

I envision one of three things happening:

 

1) You just jump to a new timeline where you do not exist because you killed the grandfather from that timeline but not the one you come from.

 

2) Your paradox unravels the fabric of the universe, destroying it.

 

3) That time would just compensate by removing the paradox, i.e. erasing the cause (you) of the paradox like casting a stone into a fast flowing stream, the course of the stream does not alter, it just flows around the rock and continues on its way. If your grandfather remained alive but you were not born then you could not go back and kill your grandfather

The same paradox can exist the other way round: you find a book describing how to build a time machine. You build a time machine and take the book back in time and leave it where you will find it. Thus enabling you to build the time machine. But where did the book come from?

You are describing a predestination paradox.