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Best Practices for Time Travelers (2003)

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Re: Best Practices for Time Travelers (2003)

#61

Post by Retra »

thinkloop wrote: post #26

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…

> There is no such thing as time [...] Time is [something that exists.]

Why even bother with this whole pointless facade? Just because you have a preferred model of time doesn't mean it doesn't exist. All things that are said to exist do so as models.

You're saying "time is fake, it's just labels" like somehow everything else in the universe isn't also just labels and just as real. Things are what they are. You find a useful way to talk about them. You don't spend your time laboring over meticulously irrelevant descriptions, ironically putting down 'mere labels' as though your whole argument here isn't just a grand exercise in label worship.

One could fairly trivially write a faithful version of your post on literally any subject. "Position doesn't exist, it's merely a manifestation of the relative relations between subsets of human experiences!" "Your HN post doesn't exist, it's merely electronic patterns in a transient configuration!"

Re: Best Practices for Time Travelers (2003)

#62

Post by cyphar »

thinkloop wrote: post #26

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…

> 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.

How do you explain acceleration? Or things like entropy that appear to indicate that the "arrow of time" does exist. Or general relativity / cosmology that clearly shows that your "snapshots of particles" appear different in different frames and there are physical effects that change how time progresses for them all.

> Time is just a way to label snapshots of particle positions in the universe.

You're not saying anything new here, apart from saying that "time isn't real". Is any dimension real? Spacial dimensions are even weirder because they're unlabelled and you can pick and three vectors to define a basis.

Re: Best Practices for Time Travelers (2003)

#63

Post by cyphar »

443633456 wrote: post #55
thinkloop wrote: post #26

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…

"There are no particles, only waves."

But waves are described by the wave equation, which is defined in terms of acceleration and curvature. Checkmate! Time is real. :P

Re: Best Practices for Time Travelers (2003)

#64

Post by cyphar »

thinkloop wrote: post #42
Mahn wrote: post #39

Earlier quoted context omitted.

OTOH time is relative to the observer and certain universe phenomena, such as black holes, can distort how time passes in different points of the space dimension. The general idea that a point in time is how we define a particular snapshot of particles is probably right, but time as a dimension also appears to be a bit more complex than how we perceive it from Earth, which we should also not forget.

"Time", aka chemical and physical reactions, can happen faster or slower depending on the environment. But this is only slightly different than putting food in the fridge. The food will mold slower, but it's not time travel. The closest we can get to faking time travel is by manipulating the speed of a subset of reactions (like our body's aging) by going the speed of light or freezing ourselves, etc. But it's still f…

So special relativity, which is a theory that comes out of thought experiments and pure mathematics, is "just a chemical reaction". How do you explain that an observer outside of a moving frame of reference will also see things differently?

Also, can you explain what you think "physical reactions" are? What causes them? Why would they happen at different speeds if time doesn't exist?

Can you explain which of the two statements you disagree with and provide an explanation:

1. The speed of light is constant in all frames of reference.

2. The laws of Physics apply in all inertial frames of reference.

If you disagree with neither of these statements, then the entirety of special relativity must follow from your logic. Which means you have to explain why these physical effects happen without being able to explain it through time dilation and other effects.

Re: Best Practices for Time Travelers (2003)

#65

Post by sudhirj »

booleandilemma wrote: post #31
thinkloop wrote: post #26

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.

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.

Re: Best Practices for Time Travelers (2003)

#67

Post by edpichler »

thinkloop wrote: post #26

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 are wrong. As far as I know, 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)

#68

Post by sangnoir »

YCode wrote: post #53
SomeStupidPoint wrote: post #51

Earlier quoted context omitted.

Your position is inconsistent: the arrangement of particles changing is time, so your explanation of there not being time... asserts that time happens! Putting the universe back as it was except for you is time travel. You've traveled your state to a different time (previous state) of the universe. Your semantic game sounds very clever, but is actually just inconsistent and borderline ignorant of what people mean by…

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.

That doesn't sound right - traveling back in time should also 'replay' random events not directly affected by the position of matter, such as radioactive decay.

Re: Best Practices for Time Travelers (2003)

#69

Post by [deleted] »

thinkloop wrote: post #26

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…

[deleted]

Re: Best Practices for Time Travelers (2003)

#70

Post by adventured »

allemagne wrote: post #43
thinkloop wrote: post #26

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…

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 any given point in time, such that you can rewind (adjust) it all back to how it was at every or any given point in time. There is nobody recording that, there is nobody to rewind it, there isn't enough energy to attempt either the recording or the rewinding at an independent macro scale (eg could you properly rewind/adjust a solar system while the wider galaxy acts upon it? would you have to rewind the galaxy? and on it goes up).

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