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Paradox-free time travel is theoretically possible

npr.org

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Re: Paradox-free time travel is theoretically possible

#12
The article makes it seem like "the timeline corrects itself." What the scientific paper actually says (as best I can understand it) is that, if the universe is entirely deterministic, the conditions necessary for time travel can only occur when the time traveling wouldn't cause a paradox. As the authors note, this isn't super relevant to our universe because:

- the conditions necessary for time travel probably don't exist

- the universe probably isn't totally deterministic

Re: Paradox-free time travel is theoretically possible

#14
It’s impossible to create a paradox, because the events that led to you being able to go back in time were created by whatever you did in the past in an attempt to change the future.

If you did successfully change the past so that you never ended up going back, you would not live the life where you go back in time to make that change. But if you did find yourself even going back in time it means your efforts already failed anyway, so might as well not even bother.

Re: Paradox-free time travel is theoretically possible

#15
post #8

Earlier quoted context omitted.

Self-fulfilling prophecy, yes. But the article reads like some sci-fi bs tbh. What's considered the 'same outcome'. If I kill baby Hitler, would the universe create another just like him? Or someone else will do same things? If someone else does them, surely it won't (for example) kill as much people. So someone dead would now be alive in the future (or vice versa). And now the outcome isn't the same yeah? Sorry but…

I find the concept absurd as well. If you do something like go back in time and murder Hitler, you're going to be impacting the actions of every single human being alive. Within a few generations there's going to be an entirely different set of people alive than the set of people alive in the universe in which Hitler was not murdered. This idea that you would still have to go back in time because the universe correct…

Perhaps it’s the paradox that makes the travel impossible rather than the physics with the infinite loops settling/converging on the scenario where time travel is not discovered / possible.

Re: Paradox-free time travel is theoretically possible

#16

> Researchers ran the numbers and determined that even if you made a change in the past, the timeline would essentially self-correct, ensuring that whatever happened to send you back in time would still happen. I'm sure these researchers are pretty smart, but nothing in this article goes beyond the level of a grade-school debate. Maybe there's something enlightening in the paper. But if there was, you'd think it woul…

Exactly. The article mentions the grandfather paradox, but doesn't really address it at all. Can't "self correct" shooting your past self in the head.
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