Why time travelling by six months using absolute positioning is a bad idea.

[Blastfrog]

Because you'll end up in outer space rather than on Earth, since it's on the opposite side of the sun at that time.

[fraggle]

Absolute positioning in what sense?

[geo]

Was this a joke? ha ha. You'd set up X Y Z coordinates and T coordinates.

[Blastfrog]

fraggle said:

Absolute positioning in what sense?

Absolute as in unchanging coordinates, so it would refer to a specific and exact 3D position within the universe. If you traveled by months, the Earth would be in a different position than it was before you traveled, meaning that you would end up floating around in space, since Earth would no longer be in the position it was in when you left.

[Chopkinsca]

If you want to go that way about it, even time traveling a second would put you in space.

[geo]

I think we're all time travelers. When we die we restart our lives over again as if for the first time. That's why there are psychics, because they remember their life previously but unknowingly and dejavu is a memory from a previous life and not a small ceasure causing your short term memory to be feel like you're remembering something.

[Blastfrog]

chopkinsca said:

If you want to go that way about it, even time traveling a second would put you in space.

If you traveled only a second, than no, you'd still be within Earth's atmosphere. I'm talking about traveling enough time to end up outside the atmosphere.

Still, you'd also end up miles away from your destination due to Earth's rotation (and either several feet above or below ground, depending where you left from) if you traveled a short enough time to not leave the atmosphere.

[eargosedown]

geo said:

I think we're all time travelers. When we die we restart our lives over again as if for the first time.

Yeah, and that lousy pistol is all we get =/

[Technician]

geo said:

I think we're all time travelers. When we die we restart our lives over again as if for the first time.

If were some kind of consciousness that continually recycle into new new beings, what explanation do you have for the exploding increase in global population? Do new lives create themselves, while older lives never truly end?

[I'myourtarget]

eargosedown said:

Yeah, and that lousy pistol is all we get =/

lols were had at this post.

[geekmarine]

You can't really have absolute coordinates, though... The universe doesn't work like that. Space itself is constantly expanding, and there is no "center" of the universe from which to base such a coordinate system. All coordinates have to be relative to something.

[Blastfrog]

geekmarine said:

All coordinates have to be relative to something.

Okay, let's say relative to the precise center of the universe (assuming such a thing exists).

[geo]

I didn't say new beings... I menat ourselves. When we die... we restart our lives. Like if you die in 2020... you're born again in 1990 and live out your life again and again and again. You just don't remember every details. You remember bits and pieces every so often, but call it dejavu or just call it a feeling.

I have an extremely long memory. I can remember some obscure name from 10 years ago that holds no significance... then it turns out I'll date that person's cousin for years. Stuff like that happens to me all the time.

Or I'll have a sleep dream of someone that gets stuck in my head along with her name and then 2 years later I'll meet her. Its weird. I'm not psychic. Its just very weird.

Or I'll get dates stuck in my head that have no meaning at all and then 20 years later after getting the date stuck in my head is the day my aunt dies. Coincidental I'm sure.

This is just one theory that we die and live again as ourselves.

[Gez]

Sodaholic said:

Okay, let's say relative to the precise center of the universe (assuming such a thing exists).

That's the point. As far as we can tell, it doesn't exist.

[Quast]

Sodaholic said:

Okay, let's say relative to the precise center of the universe (assuming such a thing exists).

The barycenter of our solar system would be the best start since it is quantifiable.

[Quast]

Sodaholic said:

If you traveled only a second, than no, you'd still be within Earth's atmosphere.

No, you would be flung out into the vacuum of space. The earth is traveling at 50,000+ mph around the sun, the solar system itself is traveling at half a million mph around the milky way.

[Sharessa]

This is why it's advisable to use a gravitonic anchor tied to your quantum singularity a neutronic stream. That way, any quantum travel is focused on the relative gravity well you left, thus leaving you in the same location on Earth even after you travel to somewhen else.

[DoOmEr4LiFe]

Quast said:

No, you would be flung out into the vacuum of space. The earth is traveling at 50,000+ mph around the sun

18 miles per second to be approximate. Well within the Earth's outer atmosphere.

[chungy]

You'd still be well dead.

[Aliotroph?]

DoOmEr4LiFe said:

18 miles per second to be approximate. Well within the Earth's outer atmosphere.

You missed the bit about the galaxy rotating. Then there's the fact that galaxies move relative to each other as well. Wherever you end up it's not likely to have any air to breathe.

Relativity does a good job making all of this pointless nonsense anyway. Practical time travel doesn't exist outside of fiction and in fiction I would simply have a rule that you don't get time travel without corresponding spacial travel. Every known method of time travel (time dilation) and every theoretical one involves moving through space anyway.

[dew]

there's a short story by isaac asimov in which two guys travel back in time to watch the sun's ignition. they do all the funky positional calculations and still end up outside of the universe.

on the other hand, geo sounds like he's tripping some phil dick balls. any flashbacks from ancient rome?

[fraggle]

Sodaholic said:

Absolute as in unchanging coordinates

Doesn't exist and cannot exist. That's the entire point of Special Relativity.

This leads to some counterintuitive results.

[Maes]

Heh I used to pester physics teachers and professors alike with questions involving relative motion and "absolute" coordinates. E.g. what would a balloon float exactly above the earth's rotation axis look like to an observer sitting right in front of it, a few meters away? What happens to a RC helicopter inside a moving elevator/ship/container?

Could a vehicle capable of absolute propulsion (float perfectly still or move in any direction at the inputted speed) leave the earth's orbit at e.g. a snail's pace if the pilot so wished, or viceversa, could it "detach" from the earth's relative entirely and be "left behind" into space in a blink of an eye? And so on :-p

[Enjay]

Sodaholic said:

If you traveled only a second, than no, you'd still be within Earth's atmosphere. I'm talking about traveling enough time to end up outside the atmosphere.

However, with the Earth spinning once every 24 hours, the surface of the Earth is moving at a little over 1000mph at the equator (again, relative to an arbitrary fixed point) and the earth travelling around the Sun at a little over 18 miles per second (or something like 1600000 mph), I think it's fair to say that you'd still be fucked even after a second. ;)

That is why it would be useful to have a time machine that could travel in Time And Relative Dimensions In Space. However, I can't think of a good name to call such a craft.

geo said:

not a small ceasure causing your short term memory to be feel like you're remembering something.

My pet theory is that I like to think of it less as a small ceasure but more as parts of the brain going out of sync briefly (even by the tiniest fraction - which is possible for a number of reasons) meaning that different parts of the brain are processing the same information at very slightly different times - meaning you are actually seeing the same event for a second time as far as the lagged part of the brain is concerned: enough for you to think you have seen it before anyway.

Either that, or they changed something in the Matrix. ;)

[Maes]

Enjay said:

However, with the Earth spinning once every 24 hours, the surface of the Earth is moving at a little over 1000mph at the equator

I remember reading an old story about some 19th century British or American crackpot who wanted to set up an international ballon-based "air cargo" system: the idea was to lift baloons up in the air, keep them "still" and let the earth rotate underneath them until they reached their preset destination (he had an idea of setting up dozens of loading/unloading stations on the Earth's parallels or somesuch), obviously based on the belief that they could remain "absolutely" still.

Unfortunately, the fact that the baloons already had Earth's rotation speed to begin with (and maintained it because the air they floated in also rotated with earth), didn't make this quite work.

I once tried the "RC heli in an elevator" scenario myself, with a relatively easy to control 4-channel coaxial. I expected that I would stuggle to keep it from hitting the floor/the ceiling when the elevator was ascending/descending but no such thing happened: maintaining a hover was almost no different than doing it on "solid" ground. If the elevator had ANY effect at all, it was only when it accelerated/decelerated.

[magicsofa]

Maes said:

If the elevator had ANY effect at all, it was only when it accelerated/decelerated.

That is exactly right. You can feel it yourself if you jump while the elevator is changing speed.
When the elevator is maintaining its speed, you and the helicopter are at rest with respect to it, so things behave as if you were standing on the ground.

What is really interesting to me is that the same type of thing happens with gravity. If you are in an elevator floating in space, you and your helicopter will float around as well. If that elevator then goes into free fall in a gravity source such as Earth, you and the copter will still float around in the same manner, even though your speed with respect to the earth is accelerating.

[Sharessa]

This discussion reminds me of that episode of Red Dwarf where they travel back into the 15th century. They're still in the middle of deep space, just now they're in the deep space of the 15th century. :P

[Maes]

I wonder how none mentioned that space missions are planned exactly by taking the FUTURE position of planets/asteroids into account, and similarly astronomical calculations enable reconstructing their past positions as well.

So, there's some "absolute" against which those missions are planned/carried out, even if it might not be "absolute with the very fabric of the universe": for missions inside the solar system, the sun itself is an absolute enough reference so that planning rendez-vous within the bounds of the solar systems is possible with "good enough" accuracy (though I don't know with good enough accuracy to place a person on the surface of a planet at a precise moment. If a spaceship misses a rendez-vous with e.g. Jupiter by 10000 km or 10 minutes, it's probably not a big deal (or at least nothing that can't be corrected to some degree by maneuvering). If YOU miss the surface of the earth by even 100 meters though...you get the picture ;-)

[kristus]

geo said:

I think we're all time travelers. When we die we restart our lives over again as if for the first time. That's why there are psychics, because they remember their life previously but unknowingly and dejavu is a memory from a previous life and not a small ceasure causing your short term memory to be feel like you're remembering something.

Add smileys when you're joking. Or someone might take you serious.

[Xaser]

Enjay said:

That is why it would be useful to have a time machine that could travel in Time And Relative Dimensions In Space. However, I can't think of a good name to call such a craft.

Hmm, I'll ask my avatar on ZDoom for a suggestion. He's pretty good with these sorts of things.

@Geo: damn. I thought you were gggmork for a second.