Ask HN: If you could go back in time | Hacker News Reader

Ask HN: If you could go back in time

1 pointlnxg33k16 comments

Would you kill kid Hitler?

I was looking at some US talks, seems to be a common question there culturally?

I was wondering, if ever we get to the point to discover time travel, would that mean that there is no free will? Everything has to happen like it was?

If you would go back in time to kill kid Hitler, there is nothing that could happen for him to change?

Would you babysit him to let him have a happy childhood?

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Have you ever wondered what if time travel was possible and we were already living in one of the optimal worlds of possibilities corrected by time travelers? Suddenly such terrible things that happened in history were inevitable because the other alternatives would have been much worse?

Never thought about it this way:0 deep

All the Myriad Ways - by Larry Niven https://archive.org/details/Galaxy_v27n03_1968-10/page/n31/m...

Not a time travel premise, but rather a parallel universe approach... for that I'd suggest The Theory and Practice of Time Travel which expresses Novikov self-consistency principle ( https://en.wikipedia.org/wiki/Novikov_self-consistency_princ...) (see also https://en.wikipedia.org/wiki/Niven%27s_laws#Niven's_Law_(Ti... ).

I'd also suggest a watch of Time Travel in Fiction Rundown - Minute Physics https://youtu.be/d3zTfXvYZ9s

If you want something longer on the subject, then Timemaster by Robert L. Forward is a good book to read ( https://archive.org/details/timemaster00forw/page/n11/mode/2... ). It begins with:

> There exist semieducated but obstinate people who have raised the concept of strict local causality to godhead, and attempt to use such words as "obviously" and "it only makes sense that . . ." in an attempt to "prove" that their version of causality cannot be violated, and that any sort of time machine is logically impossible. From my reading of the scientific literature, they are wrong. If I receive a letter from this sort of person complaining about the "impossibility" of the time machines in this novel, I will throw the letter in the nearest wastebasket . . . unless the letter is accompanied by a reprint of a scientific paper published in Physical Review (or any other reputable, refereed scientific journal), written by the person writing the letter, which proves that the paper "Cauchy Problem in Spacetimes with Closed Timelike Curves" by Friedman, Morris, Novikov, Echeverria, Klinkhammer, Thorne, and Yurtsever, is erroneous.

You'll note that history in that story remains consistent... and you can't kill Hitler.

Thank you!

If it is humanity's destiny to discover time travel and kill Hitler, it would have already (had?) happened. If time travel becomes possible we already are in the "modified" time line.

I don't know what "free will" has to do with it. Hitler had the "free will" to do what he did, has nothing to do with time travel.

Was thinking about free will because if you go back in time and kill hitler then you have decided that its his story to do exactly what we know he would do and so we’re in a predefined script doing things that we’re supposed to

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