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Scientists simulate backward time travel using quantum entanglement

thedebrief.org

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Re: Scientists simulate backward time travel using quantum entanglement

#51

Post by guyomes »

omnicognate wrote: post #49
trulyunruly wrote: post #47

Earlier quoted context omitted.

Cunningham's Law:) I was only hoping to provide some direction. But thank you for finding the right answer.

I found and posted the answer in parallel with you, and then deleted my direct response when I replied to yours (at greater length as I initially posted only the link, which was sufficient for merely answering the question). I don't think the posting of unverified ChatGPT snippets in response to factual questions on HN has value.

You have great search engine skills! Out of curiosity, what was the exact input you used, and on which search engine? I tried "adventure book girl named gedanken and grandfather on einstein theory" on Google and didn't get the right answer.

Re: Scientists simulate backward time travel using quantum entanglement

#52

Post by ben_w »

zubairq wrote: post #26

How similar is this technique to Ronald Mallett's time travel device? https://en.wikipedia.org/wiki/Ronald_Mallett

Not very. Mallet's is based on relativity while this is based on quantum mechanics, and at the moment we don't even have a good way to combine the two models of reality. Also, Mallet's would (if it worked) send stuff back in time, whereas this (if I read it right which is a big if) would make a genuinely random choice now just happen to be slightly correlated with the correct answer to the question you're about to ask.

Re: Scientists simulate backward time travel using quantum entanglement

#53

Post by [deleted] »

__turbobrew__ wrote: post #13

Something I wonder is where is the line in quantum physics where there is no experimental evidence? Obviously things like wave-particle duality have been rigorously experimentally proven, but you hear things about quantum fields, virtual particles, quantum gravity, and others and to a layperson like my self it seems like there is much less — maybe even no — experimental evidence for some of these theories. I’m always…

[deleted]

Re: Scientists simulate backward time travel using quantum entanglement

#54

Post by [deleted] »

nyssos wrote: post #36
spoonfeeder006 wrote: post #18

Is this actually simulating backward time travel? Or is it just doing entanglement? I.e. somehow entangling the state of your "gift" on day 1 with the message you receive later so that when you get the message it collapses the state of the gift to the right one?

It's just entanglement.

[deleted]

Re: Scientists simulate backward time travel using quantum entanglement

#55

Post by dvaletin »

pama wrote: post #8
andreareina wrote: post #2

Paper: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.13... > We construct a metrology experiment in which the metrologist can sometimes amend the input state by simulating a closed timelike curve, a worldline that travels backward in time. The existence of closed timelike curves is hypothetical. Nevertheless, they can be simulated probabilistically by quantum-teleportation circuits. We leverage such simul…

There is a nice explanation at the end of the letter: “While PCTC simulations do not allow you to go back and alter your past, they do allow you to create a better tomorrow by fixing yesterday’s problems today.”

Basically, having infinite budget you can send any gift you can imagine to your friend via Amazon at day-1 and cancel irrelevant orders at day-0 except correct one to make your friend happy at his BD, which is day+1. Make better future correcting your past decisions based on today information. Now the question is: how to get enough money?

Re: Scientists simulate backward time travel using quantum entanglement

#56

Post by omnicognate »

guyomes wrote: post #51
omnicognate wrote: post #49

Earlier quoted context omitted.

I found and posted the answer in parallel with you, and then deleted my direct response when I replied to yours (at greater length as I initially posted only the link, which was sufficient for merely answering the question). I don't think the posting of unverified ChatGPT snippets in response to factual questions on HN has value.

You have great search engine skills! Out of curiosity, what was the exact input you used, and on which search engine? I tried "adventure book girl named gedanken and grandfather on einstein theory" on Google and didn't get the right answer.

I had to refine it twice, IIRC, ending up with something like 'einstein book story girl "gedanken"' (the second refinement being by clicking next to one of the links that didn't include "gedanken"), for which one of the results was a New Scientist review of the book.

I did it on Google because I was on iPhone Safari, which doesn't have a good way to use Kagi by default, but I strongly prefer Kagi where possible.

Re: Scientists simulate backward time travel using quantum entanglement

#57

Post by trulyunruly »

omnicognate wrote: post #49
trulyunruly wrote: post #47

Earlier quoted context omitted.

Cunningham's Law:) I was only hoping to provide some direction. But thank you for finding the right answer.

I found and posted the answer in parallel with you, and then deleted my direct response when I replied to yours (at greater length as I initially posted only the link, which was sufficient for merely answering the question). I don't think the posting of unverified ChatGPT snippets in response to factual questions on HN has value.

I agree. I usually don’t respond with generated text. But in this instance I wanted to try to see if GPT-4 could sniff out the book that was being searched for. As of the dangers in GPT responses, it is easy to be mislead. I vetted the response (existence of author, books), but not in depth of what was actually asked for. And for that reason I failed to catch the error that you pointed out. But thank you for doing so, will definitely be more critical to GPT responses in the future. And also not post generated content that is clearly wrong.

Re: Scientists simulate backward time travel using quantum entanglement

#59

Post by goodluckchuck »

gerad wrote: post #48
DaveSchmindel wrote: post #15

Earlier quoted context omitted.

Interesting. Isn't that just problem solving? If yesterday's problems are unsolved by today, aren't they just today's problems?

I read it as: - Today, I need to predict tomorrow’s weather. - Yesterday I made some measurements of the (temperature, pressure, etc) conditions that I need for today’s prediction. - Yesterday it was impossible to know what measurements I’d optimally need to take for today’s forecast. - Today, I can (quantumly, probabilisticly) go back in time and make sure I have the optimal set of measurements for today’s predictio…

So you can measure the past, but not change it?

Re: Scientists simulate backward time travel using quantum entanglement

#60

Post by xwdv »

gerad wrote: post #48
DaveSchmindel wrote: post #15

Earlier quoted context omitted.

Interesting. Isn't that just problem solving? If yesterday's problems are unsolved by today, aren't they just today's problems?

I read it as: - Today, I need to predict tomorrow’s weather. - Yesterday I made some measurements of the (temperature, pressure, etc) conditions that I need for today’s prediction. - Yesterday it was impossible to know what measurements I’d optimally need to take for today’s forecast. - Today, I can (quantumly, probabilisticly) go back in time and make sure I have the optimal set of measurements for today’s predictio…

If you already know the optimal set of measurements why not skip the whole traveling back in time part and just change tomorrow today?
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