Wormholes and time travel

[McNutt]

I was watching a movie and they found a wormhole near Saturn that allowed them to travel outside the solar system. This made me wonder about anything in space. Does a wormhole travel with Saturn or is it locked into a set position in space? In this film the wormhole moved with Saturn and was always in the same location relative to the planet.

But let's just say it's the Star Trek universe and some anomaly is located in deep space. How would that anomaly be tracked? We know locations based on the positions of other bodies and those positions are always changing. So if this wormhole was next to Saturn, would it still be next to Saturn in a year or would we have no idea where it is because Saturn and the rest of the solar system has moved?

Likewise, let's take a look at Back to the Future. Marty travels back in time 30 years in Doc's DeLorean. If Marty is at the Twin Pines Mall and instantly travels back in time, what keeps him at the mall's location? Would he not travel back into empty space because the Earth wasn't right there 30 years ago? If he were to travel back in time one minute would he find himself in the Earth's crust?

I realize these are both movies and you have to go with it. But this is what keeps me up at night.

[YellowKing]

If Marty is at the Twin Pines Mall and instantly travels back in time, what keeps him at the mall's location?

I've always assumed that Doc accounts for this in the time machine, so that it's not only going back in time, it's calculating the correct location offset so that the DeLorean doesn't find itself in outer space, under the ocean, materializing into the interior of a mountain, etc.

The only problem is that there would be no guarantee you wouldn't materialize into a car or a person, or any other sort of obstacle (to be fair, Marty kind of does this when he first goes back to 1955 and crashes through the barn). You'd have to hope to get lucky, or possibly you could build some kind of sensors in the time machine that would make it not materialize if it somehow sensed an obstacle within x number of feet. How you have it sense that *before* it actually arrives I don't know, but hell, it *is* a time machine.

I think that aspect is fudged a LOT in time travel media, though I have read books that take it into consideration.

[Unagi]

I believe you are over thinking it (maybe).

A point of reference in space, is only that.


On Earth, property surveyors have the same issue when it comes to plate tectonics. No one point is eternally "fixed".

Where a thing is, is in reference to other things. If they all are moving apart it's expansion. If they are all moving together, well - they are not moving with respect to one another.

Our sun would be used as a reference place for that wormhole (if it wasn't magically locked to Saturn's orbit, and if it is - then magically we have a reference point of Saturn). Or if that wasn't helpful, I suppose the center of the milkyway may be.

Am I talking about what you are talking about, or am I missing the point.

[McNutt]

Yes, that's what I'm talking about. However, it's not just Saturn's position from the sun that's changing as it orbits. The sun is also moving and it would be near impossible to pinpoint the fixed location of an object in space when absolutely nothing else is fixed.

[McNutt]

How you have it sense that *before* it actually arrives I don't know, but hell, it *is* a time machine.

There is a scene in Terminator 2 where a sphere opens up with the robot transported from the future within and you can see how anything from the present within the sphere was gone.



Where did that stuff (truck corner, asphalt) go? Did that matter get transported to the future or did it disappear forever?

[Unagi]

Yes, that's what I'm talking about. However, it's not just Saturn's position from the sun that's changing as it orbits. The sun is also moving and it would be near impossible to pinpoint the fixed location of an object in space when absolutely nothing else is fixed.

Right, but you pre-suppose some grid that we would apply it to.

In reality any "grid" of coordinates needs to pick its 0,0 -

So, if the center of the galaxy isn't "non-moving" enough for your calculations ("to ->pinpoint<- the fixed location"), you will then look for one that does. (center of the universe?)

If the expansion of the universe isn't fixed or and is at an unknown rate that messes with your calculations, you could miss your target - but we don't deal with that level of pinpoint. And there is no such thing as a 'fixed location' to "pin point" in that sense anyhow.

[Unagi]

Where did that stuff (truck corner, asphalt) go? Did that matter get transported to the future or did it disappear forever?

So, here is how that works ( )...

Matter can't just spontaneously exist and then not exist willy-nilly.
There are just some fundamental laws of physics that can't be ignored.
So the real trick in this time-travel bubble is that it "consumes" exactly the same amount of energy/matter that it aims to produce in the time-line. If they sent a small child, the diameter of the sphere would have been smaller.

So, the back of that trailed and asphalt became energy and then returned to a state of matter that became T2.

Back in T2's time-line, the robot just "poofed" - and they have it down to a science - where they don't obviously don't get "sent asphalt and truck parts" - but instead they push energy into the system to make up for the lost matter (T2) in their time-line.


I hope that clears it up for you.

[stessier]

And there is no such thing as a 'fixed location' to "pin point" in that sense anyhow.

There might be - it could be outside of the observable universe. That would be pretty neat.

[Unagi]

Okay, but if it's unobservable - then I'd argue it may be hard to find and use.

[Smoove_B]

You're obviously not accounting for the anchoring particles - which we've yet to discover - that provide what amounts to temporal GPS information, making sure to connect each end of the wormhole to a corresponding location in the universe.

[stessier]

Okay, but if it's unobservable - then I'd argue it may be hard to find and use.

We can't observe it. But if someone is on the edge of our observation, and they could see more, and we could communicate with them in something like real time...then the real fun can begin!

[Isgrimnur]

Time is subject to gravity as well, so it's not a problem.

[Isgrimnur]

Okay, but if it's unobservable - then I'd argue it may be hard to find and use.

We can't observe it. But if someone is on the edge of our observation, and they could see more, and we could communicate with them in something like real time...then the real fun can begin!

It'd beyond the environment. There's nothing out there.

[stessier]

Okay, but if it's unobservable - then I'd argue it may be hard to find and use.

We can't observe it. But if someone is on the edge of our observation, and they could see more, and we could communicate with them in something like real time...then the real fun can begin!

It'd beyond the environment. There's nothing out there.

We don't know that. And it would be really weird if we really were the exact center of the universe, unless it really is a simulation.

[Isgrimnur]

[Jaymann]

Empty space in outer space is not 100% empty, there are a few particles floating around. So if you went through a wormhole you might annihilate those particles and yourself. Even if you survive, you are probably not coming back.

[McNutt]

Libera te tutemet ex inferis!

[Jaymann]

Yeah, well so's your old man.