Entering a closed timelike curve tomorrow means you could end up at today. Credit: Dmitry Schidlovsky
Posted on 09/03/2014 1:11:14 PM PDT by BenLurkin
Recent experiments offer tentative support for time travel's feasibility—at least from a mathematical perspective. The study cuts to the core of our understanding of the universe, and the resolution of the possibility of time travel, far from being a topic worthy only of science fiction, would have profound implications for fundamental physics as well as for practical applications such as quantum cryptography and computing.
Closed timelike curves The source of time travel speculation lies in the fact that our best physical theories seem to contain no prohibitions on traveling backward through time. The feat should be possible based on Einstein's theory of general relativity, which describes gravity as the warping of spacetime by energy and matter. An extremely powerful gravitational field, such as that produced by a spinning black hole, could in principle profoundly warp the fabric of existence so that spacetime bends back on itself. This would create a "closed timelike curve," or CTC, a loop that could be traversed to travel back in time.
Hawking and many other physicists find CTCs abhorrent, because any macroscopic object traveling through one would inevitably create paradoxes where cause and effect break down. In a model proposed by the theorist David Deutsch in 1991, however, the paradoxes created by CTCs could be avoided at the quantum scale because of the behavior of fundamental particles, which follow only the fuzzy rules of probability rather than strict determinism. "It's intriguing that you've got general relativity predicting these paradoxes, but then you consider them in quantum mechanical terms and the paradoxes go away," says University of Queensland physicist Tim Ralph. "It makes you wonder whether this is important in terms of formulating a theory that unifies general relativity with quantum mechanics."
(Excerpt) Read more at scientificamerican.com ...
The next time we get another Tesla or Einstein, we’ll be doing this.
I already read this article next Wednesday.
“An extremely powerful gravitational field, such as that produced by a spinning black hole, could in principle profoundly warp the fabric of existence so that spacetime bends back on itself.”
Old news! This the the known cause of the FR double-posting bug. You make a post. As you hit the Submit button spacetime folds back on itself and there are two posts instead of one.
“Quantum Leap” had this all figured out a decade ago...
Then send me back to 1940 so I can live in the greatest era of the USA then hopefully have died sometime during the Bush 41 years, when it faded, having enjoyed a spectacular retirement.
I’ve always wondered about that.
I just knew it couldn’t be MY fault.
I think Bester and Zelazny came up with the best answer. Basically it came down to Earth is an insignificantly tiny piece of the universe and if we get a couple of small paradoxes once in a while it just doesn’t matter.
I didn’t read the article, so tell me. Do I still need a Delorean? Or can we do without these days?
I’ll gladly pay you Tuesday for a hamburger today if you explain it to me last Monday.
I’d like to go back to 1890 with two backpacks.
One full of gold coins. The other with penicillin.
No Delorean required. Just some means of flying at near light speed around the periphery of a massive black hole.
I am already researching this at the department of redundancy department where I am researching this.
Uh-oh. I gave a buck to a gnarly, beat-up, angry old wino who cursed me for it and said “you young punk, you’re going straight to hell” and apparently it was me.
Your timeline included Vietnam and all its stupidity. Go back further.
Makes me wonder if some of the astronomical observations are off in time calculations due to black hole intereference
Going back to give stanley ann dunham some bc pills..... not coming back or it will undo the timeline changes. Wish me luck. Going to the grassy knoll later and yelling “duck”!
Two full of penicillin, sell the penicillin for gold coins, then bring them back here and sell them. Repeat.
The Cathedral of Chalesm was a building used by Slartibartfast and the Campaign for Real Time as an example of the hazards of temporal manipulation. The cathedral was scheduled for demolition in order to build a new ion factory. However, due to delays in construction and a strict deadline for the start of ion production, the beginning of the project was extended so far back in time that the cathedral ended up never having been built in the first place. As a result, picture postcards of the cathedral suddenly became immensely valuable.
Tangent here, but I’ve been wondering if this whole time travel business can show why materialists are far too hasty in denying the reality of the soul.
If I can go back to 1981, then somewhere there has to be a 1981 to go back to. Which means that everyone that was alive in 1981 is actually still alive there, no matter what happened to them subsequently.
Perhaps time is like floating down a river—just because you experience it as a unidirectional motion doesn’t mean the sights you saw along the way cease to exist.
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