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Can We Escape from Time?

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31–36 of 36 posts

Re: Can We Escape from Time?

#31
post #23

The reason we can't go back in time is that time and information (and hence consciousness, which is made of information) are inextricably linked by quantum physics: http://blog.rongarret.info/2014/10/parallel-universes-and-ar...

Your post explains why going back in time along the same path is pointless because you lose the information. But maybe we could take a different path (closed timelike curve) and keep the information.

Re: Can We Escape from Time?

#32
post #23

The reason we can't go back in time is that time and information (and hence consciousness, which is made of information) are inextricably linked by quantum physics: http://blog.rongarret.info/2014/10/parallel-universes-and-ar...

Your post explains why going back in time along the same path is pointless because you lose the information. But maybe we could take a different path (closed timelike curve) and keep the information.

> going back in time along the same path is pointless because you lose the information

No, it's much deeper than that: the accumulation of information is what creates time.

> closed timelike curve

This is at the limits of scientific knowledge so there's nothing definitive one could say about it at this point. But you might want to read this:

https://www.scientificamerican.com/article/time-travel-simul...

Re: Can We Escape from Time?

#33
post #20

A pretty substantial flaw in the piece, almost enough to sink it, is the suggestion that Looper is somehow more worthy of calling out than Primer. Tsk... somebody sack the fact checkers... Primer: http://www.imdb.com/title/tt0390384/ (Interesting not least because its budget was about 50p)

It's a REALLY confusing film, but absolutely brilliant in the way that it shows just how confusing a world with time travel would be[1]. The way everything escalates in the latter half of the film is insane. For a "simple" explanation of the plot, see [2]. Since this analysis was done by a third party, it's obviously hard to be sure that this is fully correct, but it at least seems very close. [1] For anyone able to…

Also recommended: Primer commentary track. Run it beside the movie, and it'll drop in to explain things as they happen.

https://qntm.org/commentary

Re: Can We Escape from Time?

#34

Earlier quoted context omitted.

It's a REALLY confusing film, but absolutely brilliant in the way that it shows just how confusing a world with time travel would be[1]. The way everything escalates in the latter half of the film is insane. For a "simple" explanation of the plot, see [2]. Since this analysis was done by a third party, it's obviously hard to be sure that this is fully correct, but it at least seems very close. [1] For anyone able to…

Also recommended: Primer commentary track. Run it beside the movie, and it'll drop in to explain things as they happen. https://qntm.org/commentary

Hadn't heard of this before -- I am sooo going to try this. Thanks for the link!

Re: Can We Escape from Time?

#35

Earlier quoted context omitted.

I wonder. If the universe is deterministic, and nothing is random, then Time could be thought of as a vector whose values encompass all the properties of everything in existence and the direction of changes in each of them. If we knew all the "rules" that govern those changes and could make a simulation that captured the current state of everything, we could traverse back and forth along that vector (but probably not…

This was a prevalent idea in physics till quantum mechanics burst into the scene. I don't remember where I saw it, this the most convincing argument I heard regarding simulating future: Our universe is actually the most efficient computer that can simulate the future with our physical laws. Meaning, at any given time, it is not actually executing a pre-determined program, it is busy computing the future.

You don't really need quantum mechanics for this argument, though. Even in a non-quantum world, non-linear and, in particular, chaotic systems effectively prevent you from predicting the future. While you could do it in theory, in practice you would need do know every single variable very precisely because the outcome of chaotic systems can change drastically due to a small change in initial conditions (which is colloquially known as the butterfly effect). Quantum mechanics just makes this even harder or downright impossible (think of determining the exact values of the wave function or predicting the outcome of measurements). But even if we did know all the variables, we'd then still need to simulate every single atom to predict the future, so we'd basically be building another universe. So, you're right, in that sense the universe is the most efficient computer simulating our physical reality.
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