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Can We Escape from Time?

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Re: Can We Escape from Time?

#21

Post by lomnakkus »

to3m wrote: 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 observe the multiple time lines, obviously. :)

[2] https://i0.wp.com/media2.slashfilm.com/slashfilm/wp/wp-conte... (massive SPOILERS, obviously)

Re: Can We Escape from Time?

#22

Post by jayisbatman »

dom0 wrote: post #12
WJW wrote: post #6

Earlier quoted context omitted.

Technically the fourth variable that a receiver solves for is the clock error in the receiver, not the actual time (though that then follows easily enough). The system of equations is only solvable because it is assumed that the clock error of the satellietes relative to each other is zero. I'm not convinced though that time dilation is the same for all the satellites, since they are not all in the same orbit. Since…

> According to [0] the clock drift due to relativistic effects would be over 45000 nanoseconds per day. Between an uncorrected satellite and the receiver. This error is already removed through the fourth variable, only the average error of the satellites used for this remains (assuming perfect receiver etc.). So even if the satellites where not corrected the positioning error would not be "XY kilometers per day and c…

The location calculation is completely dependent upon relativistic time dilation.

The Navistar satellites have an orbital speed of 8,750 MPH (more than 2 miles per second, relative to our earth surface frame), they are subject to a relativistic time dilation adjustment of -7201ns (slower than our earth surface frame). The location calculation cannot ignore that. The GPS signal (radio) takes on average 1 foot per nanosecond (perhaps a slightly bit more, but this is electromag radiation in a non-vacuum). If your receiver didn't account for this you would be more than a mile from your actual location. Relativity and its time dilation are required for any satellite based location system -- unless your satellites are at altitude of zero.

Re: Can We Escape from Time?

#24

Post by nol13 »

The basics for time travel start at CERN in about a year and end in 2034 with the first "time machine" built by GE. Too bad we can't post pictures or I'd show it to you.

Re: Can We Escape from Time?

#25

Post by heydenberk »

nol13 wrote: post #24

The basics for time travel start at CERN in about a year and end in 2034 with the first "time machine" built by GE. Too bad we can't post pictures or I'd show it to you.

To still be in this timeline, we need to retcon Titor's 2015 nuclear war.

Re: Can We Escape from Time?

#27

Post by ChuckMcM »

nol13 wrote: post #24

The basics for time travel start at CERN in about a year and end in 2034 with the first "time machine" built by GE. Too bad we can't post pictures or I'd show it to you.

I realize that time travel is not invented in my lifetime, if it had been I would have traveled back to tell myself to get out of tech stocks in 1999 :-)

Re: Can We Escape from Time?

#28

Post by NumberCruncher »

bitL wrote: post #15

Are we capable of existing outside time? Imagine instead of living in an [array of time-frames], moving in one direction, i.e. time, in a single frame only, like a snapshot (even with the possibility to observe the whole [array of time-frames] at once). Would you have any words to describe it? I think all our mental models would just collapse.

Some people say time is just an illusion we use to process reallity as an [array of time-frames]. I think what you are looking for is a kind of enlightening which in this case would mean stepping out of the illusion of time. Some people reported to achieve this with meditation and/or psychodelics.

Re: Can We Escape from Time?

#29

Post by yarou »

bitL wrote: post #15

Are we capable of existing outside time? Imagine instead of living in an [array of time-frames], moving in one direction, i.e. time, in a single frame only, like a snapshot (even with the possibility to observe the whole [array of time-frames] at once). Would you have any words to describe it? I think all our mental models would just collapse.

The closest existence I can think of is being trapped in a singularity. An observer would obviously see your body obliterated in mere seconds, but time would exponentially slow down on your end.

Re: Can We Escape from Time?

#30

Post by charlieflowers »

jacobolus wrote: post #17
brianberns wrote: post #5

"'There is no difference between Time and any of the three dimensions of Space except that our consciousness moves along it,' says the Traveller. That turned out, amazingly and counterintuitively, to be true. 'In surprisingly short order this notion would become part of the orthodoxy of theoretical physics,' says Gleick." What? Spacetime does contain four dimensions, but the whole reason that time travel is fiction,…

You’re right that “There is no difference between Time and any of the three dimensions of Space [...]” is kind of misleading, but it’s only half wrong. The special relativity story is more nuanced. There’s no single “time direction”. Which direction in spacetime looks like “time” vs. a mix of “space” and “time” movements vs. “space” depends on your reference frame. Every “faster-than-light velocity vector” can be con…

Reminds me of the final book in the Hitchhiker's Guide "trilogy". The advanced version of the Guide is calibrating itself so it can perform "reverse temporal engineering" on behalf of Ford.

It asks a series of questions, one of which makes no sense, and then says something like, "Oh, time travels in that direction for you."

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