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Best Practices for Time Travelers (2003)

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Re: Best Practices for Time Travelers (2003)

#71

There is no such thing as time, or time travel. There are only positions of particles. To go back in time by 1 minute, all particles in the universe have to be moved/changed back to their previous position. This is not time travel, but universe manipulation except for one subject. If there were parallel universes with every possible outcome and you traveled to one, this would also not be time travel, but a moving to…

You make a good point. What if a civilization figured out how to do this on a local level? To finely manipulate particles within a small area? It would be like version control for reality.

Each particle has is own time. Each particle can go forward on time, independently.

That's why satellites clocks must be adjusted https://en.wikipedia.org/wiki/Time_dilation

Re: Best Practices for Time Travelers (2003)

#73
post #65

Earlier quoted context omitted.

You make a good point. What if a civilization figured out how to do this on a local level? To finely manipulate particles within a small area? It would be like version control for reality.

This idea is referenced quite a bit in an Asimov novel, but I can't remember the name. Something about earth in the far future, and called Eternity Circuits. Computers enforce physical arrangement at an atomic level, and redundancy circuits enforce the computer and each other, basically creating systems that last forever.

Arthur C Clarke, The City and the Stars: https://en.wikipedia.org/wiki/The_City_and_the_Stars

Re: Best Practices for Time Travelers (2003)

#74
post #53

Earlier quoted context omitted.

I think what he means is that time exists in the way that distance or speed exists. It's not a physical force like gravity or magnetism that acts upon the universe, it's just a method for us to understand and quantify what happens around us. Traveling back in time subsequently doesn't make sense because the "past" is simply what we call previous configurations of matter. You can't go back to those configurations (rea…

> Traveling back in time subsequently doesn't make sense because the "past" is simply what we call previous configurations of matter. So? If my future goes from the world as it is now to the world as it was in 2000, in what sense am I not in 2000? I mean, you guys seem to be under the impression that there's a single universal clock I cant reset... There's not. In whatever sense it ever was 2000, rewinding all the cl…

Unlike distance, time is unidirectional. Yes, if you could roll back all matter, energy and every other force in the universe you could "go back in time" but the point is that time is a concept and not a force of nature.

It seems like you're being obtuse about the distinction.

Re: Best Practices for Time Travelers (2003)

#75
post #74

Earlier quoted context omitted.

> Traveling back in time subsequently doesn't make sense because the "past" is simply what we call previous configurations of matter. So? If my future goes from the world as it is now to the world as it was in 2000, in what sense am I not in 2000? I mean, you guys seem to be under the impression that there's a single universal clock I cant reset... There's not. In whatever sense it ever was 2000, rewinding all the cl…

Unlike distance, time is unidirectional. Yes, if you could roll back all matter, energy and every other force in the universe you could "go back in time" but the point is that time is a concept and not a force of nature. It seems like you're being obtuse about the distinction.

Your position is just semantic games: traveling to a past state of the universe and living there is time travel -- you translated your state in to a past configuration of the universe. You're just sitting there whining how what both scientists and lay people would accept as time travel (living in the past) isnt Real Time Travel, because it's not some fictionalized Platonic ideal you've constructed and insist is the One True Meaning.

Amature science people are the worst: a little knowledge keeps you from seeing the picture.

Re: Best Practices for Time Travelers (2003)

#76
post #74

Earlier quoted context omitted.

Unlike distance, time is unidirectional. Yes, if you could roll back all matter, energy and every other force in the universe you could "go back in time" but the point is that time is a concept and not a force of nature. It seems like you're being obtuse about the distinction.

Your position is just semantic games: traveling to a past state of the universe and living there is time travel -- you translated your state in to a past configuration of the universe. You're just sitting there whining how what both scientists and lay people would accept as time travel (living in the past) isnt Real Time Travel, because it's not some fictionalized Platonic ideal you've constructed and insist is the O…

Your patronizing tone aside I see what you mean. Yes, that would be "time travel". Again, it just seems like you're being antagonistic here and now putting words in my mouth in a vain attempt to prove your own superiority.

The only claim I was making was to clarify what OP meant about time not being a phenomena like gravity and to passively ask if there was any evidence of time as a physical (rather than purely conceptual) force.

Sorry if my amateur curiosity offended your professional (?) understanding of such things.

Re: Best Practices for Time Travelers (2003)

#78
post #76

Earlier quoted context omitted.

Your position is just semantic games: traveling to a past state of the universe and living there is time travel -- you translated your state in to a past configuration of the universe. You're just sitting there whining how what both scientists and lay people would accept as time travel (living in the past) isnt Real Time Travel, because it's not some fictionalized Platonic ideal you've constructed and insist is the O…

Your patronizing tone aside I see what you mean. Yes, that would be "time travel". Again, it just seems like you're being antagonistic here and now putting words in my mouth in a vain attempt to prove your own superiority. The only claim I was making was to clarify what OP meant about time not being a phenomena like gravity and to passively ask if there was any evidence of time as a physical (rather than purely conce…

Im mostly replying to say that you're correct I was needlessly antagonistic, and that Im sorry for that.

To try and answer your point a bit more directly: time isn't a force, just like distance isn't a force. A force is something that induces action. If you experience a force, you're induced to act. (Some debate about if gravity is a genuine force, but that's getting messy.)

Time is what a clock does, and distance is what a ruler does. On the one hand, both time and distance are mathematical fiction to parameterize aspects of the universal state. On the other hand, Im 2m tall and my clock is making a periodic tick noise. So, time and distance really are aspects of phenomena, rather than phenomena in their own right, and as such are fiction. However, the aspects of phenomena they refer to have so far turned out to be pretty useful and appear in most phenomena we've encountered, and we think this is because both emerge from aspects of the fundamental phenomenon interacting with itself to create the other phenomena. (This is why we're trying to unify QM and GR, and why the approach is based on entanglement and information cascades.)

My point was that there's no fundamental difference between time and distance, they're either both there or both not there in exactly the same sense, we can travel through both in the same sense (if not same freedom), but only very rarely do people get insistent that distance doesnt exist, and usually only when making a highly technical point. Never have I had someone not understand what I mean by moving a foot to the left, even if they ultimately don't believe that distance exists. This comment was like that: insisting we talk in the highly technical language of distance not existing, but refusing to make the standard and well understood lift of "move a foot to the left" to that language. There's a very straightforward notion of travel, even if we're talking about around a parameter space. It's that partial use of technical machinery that frustrated me -- if you're going to have a technical discussion, don't play obtuse and refuse to make reasonable translations if other people's statements. My comment about people who know a little was mostly just venting frustration that people who are new to the highly technical aspects often can't (and don't even realize they should) make those lifts, then end up stridently talking about how the unlifted claim makes no senae in their freshly learned framework. To be fair, I was worse about that than most, and should learn to be extra patient.

My snarky comment was snarky, but had a point: time is one of the open questions in modern physics, and unless you really want to get in to the heavy stuff, less is more. About the best view to have in your head is "there's no time but what your (and everyone else's) pocket watch says". Your watch needn't agree with mine, though. (And indeed, your head is a slightly different age than your feet, from all the standing, sitting, etc in a gravity well.)

To summarize, Id say that time and distance are meta-phenomena: they're consistently behaved, widespread features of phenomena we discover, but we have good reason to expect that it's an emergent feature of a deeper phenomenon.

Again, sorry for my earlier replies, and I hope I havent put you off asking questions!

Re: Best Practices for Time Travelers (2003)

#79

the earth spins around the sun. the sun spins around the milky way. so if one where to time travel wouldn't they just pop into a space where we are now but where the earth hasn't reached yet?

Relativity tells us that there is no preferred reference frame. Earth is just as "special" as the center of the galaxy.

Re: Best Practices for Time Travelers (2003)

#80

Earlier quoted context omitted.

Time travel is dubious, but in what useful sense is there no such thing as time? Define the phenomenon of time dilation or just the concept of motion without it. Particles go from position to position... but describing being at state X and then being at state Y seems to strongly imply the existence of what we understand as time.

Time doesn't exist in the sense that it's just a measurement. I'm 6'2", that height does not exist as a tangible thing, it's a mathematical device. Whether we're talking about 60 seconds, or 6 billion years, they're both measurements of distance traveled / motion. We measure one year by the earth's relationship to the sun. Time travel cannot exist because the universe does not keep a record of where everything was at…

The argument about time seems plausible. I don't think time travel is possible either. I do however think there is such a thing as time and height. Units of measurement are certainly arbitrary but there is something that is being measured.
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