Time Travel

Have you seen The Terminator? How about Back to the Future? Hiro Nakamura from Heroes? Time travel has been portrayed in fiction as the possibility to visit the distant past or the near future... but how serious is this time stuff?

In all honesty, I do not believe it is possible to travel "through" time.

Although, a ship that leaves earth's atmosphere and *approaches* the speed of light would return to appear younger than those who witnessed the event from land. The more intense the gravity the "slower" time progresses. Clocks aboard ships generally read seconds slower than clocks on earth and when the passengers return they appear to have traveled into the future.

But what about going backward in time?

This is the part that throws me for a loop, because I simply cannot understand it's possibility. To me, it *could* be possible to travel into the "past" if one were capable of traveling faster than the speed of light. Of course, this is absolutely impossible as the speed of light is the cosmological *speed limit* of the universe. But if it were possible, would you not travel so fast that time itself would stop and you could inevitably beat the data transfer of light before it had a chance to be "formed"? (confusing I know)

We'll just throw it out though.

But then there's wormholes. Wormholes connect two distant "parts" of space-time, the entrance could be close to earth and the "exit" would be elsewhen in the universe. Of course, opening a wormhole is currently beyond our technology, there is the possibility that wormholes open naturally throughout space.

Now... if the universe is infinite and one traveled through a wormhole and it collapsed as you reached the "other side", it is my point of view that without some sort of universal GPS system to re-open wormholes to the point of origin, you would be effectively trapped in this parallel universe. There is any number of infinite possibilities when it comes to universal travel through wormholes, you could open a hole to one part of the universe and never see it again.

Also, the Grandfather Paradox. If you traveled through a wormhole to planet earth 80 years ago and killed your grandfather, who would have given birth to your father and then you, the idea is that you wouldn't exist. BUT from my PoV, wouldn't you be in a completely different parallel of the earth universe? Thus you would only kill the line in that reality, not in your own. Also, if you WERE to "disappear" like Marty McFly, wouldn't that violate the laws of quantum physics, stating that information can never be truly lost?


Just my ideas, enjoy feedback.

There's going to have to be away to adjusted our matter and put it all bacK togther, You know cells and what have you.

IMO there lays the problem

Like the transporter from Star Trek?

It's a possibility, but then in order to use it long distances you'd need a receiver however far away you wish to travel.

https://casa.colorado.edu/~ajsh/schww.html

Oh the possibilities.......sigh

The gravity of a ship traveling would not need to increase, time simply slows down due you your travel not as a result on increased gravity. This is no more time travel than we do now, you are constantly traveling into the future even as you read this. However there is no jump through time only a different rate of time.

You presume that a wormhole would have a width, it doesn't need to, it could simply be one part of space connected to another so there would be no inside.

Different timelines is one possibility put forward to the grandfather paradox you mention.

There is no real reason to assume that going faster than light will cause you to travel backwards in time, this can and will never be tested as you can't beat relativity.

As for teleportation, there are problems with that, you can't know where a particle is and where it is going at the same time so thats where the problem of reconstruction lies, although quantum entanglement is a possible soluion it is a very long way into the future before anything more than a photon is teleported.

Would a wormhole have a length? Or any dimensions at all?

If space is 3-dimensional, then a wormhole should observe at least 1-dimension, right? Even if it was absolutely minute, say the bridge the wormhole creates between two points in space was equal to the Planck length, although incredibly tiny it would still be a "measurable" (even if it isn't measurable) and therefore have dimension to it.

But I hear all this about information travelling through a wormhole causes it to collapse, are they referring to it's wave function or the "hole" itself?

Michio Kaku postulates that wormholes could be sustained using negative energy/matter. (I don't know if he was the first, but he's the one I know of)

It can have 2 dimensions, it doesn't need to have a third, how many dimensions does a hole have?

Wormholes are just theory, there are many theories about what would happen when traveling through a wormhole. Negative energy would possibly fit the equations but where do you get this negative energy.

Hypothetical questions don't have definate answers.

All you need is a Flux Capacitor.

I would assume that a hole itself has no dimension, but given the idea of a wormhole and the connection one could have to another point in space-time would be very similar to a blackhole in the Einstein-Rosen bridge idea.

An Einstein-Rosen bridge would collapse without letting even light through unless held open with exotic matter.

I have never seen a wormhole so do not know what dimensions it would have but i don't think that a wormhole closing on you would send you into another universe, it would simply destroy you or spit you out one end.

I like the @Stargate@ thoery of a machine that can create a stable wormhole.

It would have a hight and a width but the depth would be in the 4th dimension.

But time travel would mean you would have to leave one 'gate' in the past and use the one in the present to move to the one in the past.

Technically if you move one end of a wormhole and travel to it you will be travelling through time.

At every instant every atom would need to be located in a so called past so that those atoms would be there when you got there.

Now if that seems remotely likely to anyone then you have already time travelled.

I did think that if you were on a galaxy at the edge of the universe you would see the light from the earth from 14 billion years ago but apparently light does not last forever before it becomes corrupted so then I wonder how they get the light from these furthest galaxies if that is the case.

john

I'm travelling into the future right now.

....sometimes it only feels like i'm going half normal speed though

You can't accomplish time travel. You can't go to the past, because it already happened. In order to go back in time, the environment would be completely different, and the people there would be dead. And you simply CAN'T go into the future because it hasn't happened yet!!