Can We Escape from Time?
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Einstein's time dilation has practical consequences: aside from being able to observe the slowdown in atomic clocks taken up in airplanes and the many consequences in astronomy, we also have GPS, which would not work without taking relativity into account. If GPS doesn't count as a 'consequence' or 'outcome' due to a non-traditional understanding of time, nothing does!
The time dilation is therefore only compensated so that you can use a GPS receiver as a very accurate, absolute clock.
Since the system works by determining signal delay between the satellite and the receiver and the signals move at (rougly) the speed of light, even an nanosecond error in time is already a 30 cm error in position. According to [0] the clock drift due to relativistic effects would be over 45000 nanoseconds per day. So keeping the clocks synchronized for all the satellites is crucial and relativistic corrections are super important for accurate positioning.
[0]: http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps....
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 climbing", the much smaller difference in time dilation between satellites would remain though.
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.
Primer: http://www.imdb.com/title/tt0390384/
(Interesting not least because its budget was about 50p)
[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)
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.
http://blog.rongarret.info/2014/10/parallel-universes-and-ar...
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...
What? Spacetime does contain four dimensions, but the whole reason that time travel is fiction, rather than fact, is because the time dimension is different from the space dimensions.
We can predict the future and recall the past, just not in a scale that is practical for our mundane lives. Personally, I think this is a humility lesson: in the grand scheme of things, the entire span of a human life is less than a tiny drop in the ocean of time.
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 considered the direction of “time” for some observer, just as every “slower-than-light velocity vector” can be considered a direction in “space” for some observer. A vector like “the vector difference between the position of the earth now and the moon half a second in the future” (by our measurement) is, for some other reference frame, a pure movement in time. In just the same way, “the vector difference between the position of the earth now and the moon two seconds in the future” is a pure distance in space indicating simultaneous-in-time events, for some other reference frame.
Or perhaps we should even say that the “reference frames” and a split between space and time dimensions are an abstract concept that we impose on top of the 4-dimensional spacetime. We can work out all of our physics in a 4-dimensional context without explicitly splitting “space” from “time”. https://en.wikipedia.org/wiki/Spacetime_algebra#Spacetime_sp...
In just the same way, if you have a two-dimensional Euclidean plane with no externally imposed markers on it, there’s no inherent notion of “up” or “left” – those depend entirely on what kind of reference you pick. Imposing some specific coordinates is sometimes useful for understanding the geometry and solving particular problems, but itÍ’s in some ways arbitrary.
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."
Events are a stone being dropped into or skipped along the surface of that pond. The waves produced by the event are viewable from all angles. The actual event -the stone drop- occurs only once. The event is immutable, even though the ripples persist and are measurable.
We may eventually be able to view the ripples in more detail, and see past or future events. The events themselves though, are immutable. They've already occurred or have not occurred yet. The stone does not change. The interaction between stone and surface does not change. What changes is our ability to decipher data from that event, not the event itself.
BTW, conversation laws are hinting to an illusory nature of time. Change of compound structures do exist and it is in everything we are able to observe. But the whole is unchanged, no matter what fancy theories or simulations would say.