Time travel

[Damp Squarie]

Yes this is only a hypthetical! If humans eventually found a way to travel back in time, and you did so, and killed your grandfather. What would happen? Could you actually kill him? Because if he ultimately made you, then it is impossible... Could it be done if humans had the ability to time travel??

Now ive got you all stumped! (dont worry i am to!!)

 

[Milkman]

Or what if you travelled back in time 70 yrs, met somebody you fancied and conceived a child with them? Surely upon your return to 2003, you'd be a single parent raising a pensioner.

 

[ozzult]

You've all seen Back To The Future, if you mess with continuum, you're ****ed!

 

[CharlieG]

If you killed your grandfather after he conceived your mother/father, then you should exist, correct?

I wonder what would happen if you went back in time within your own lifetime... would two entities be able to exist, or would one die/disappear or whatever?

 

[Cyclops]

If you posit a Universe is a linear string of moments motoring along on causality (a happens & makes b happen which makes c happen) then there is a paradox with time travel, because to kill your ancestors would remove your cause. The linear string wouild break or at least radically alter, so probably it isn't possible in this kind of Universe.

If the Universe is a random agglomeration of moments which our intellects mistake as a sequence, then such an "event" is possible. Our existence which seems to have a cause and effects is simply a ripple in disorganized matter, an illusion so any change is just another illusion.

Another possiblity is that time isn't a continuum but just another dimension, albeit one we have not yet learned to move in (other tha forwards). Think of time as a road-we are like a child stuck in a car driving down the road, seeing trees and houses go past. Trying to make sense of the parade of images we evolve a simple idea of causality-we saw the tree first, then the house. Maybe the tree caused the house?

If we could control the car, we could reverse, go left or right, have a look at the trees and houses and get a better understanding. Blowing up a garage a few blocks back doesn't stop or journey from ever beginning.

If the events in time exist as dimensional points, we might be able to alter points across the 4 dimensions without neccesarily harming ourselves. Do we exist because of an event spatially and temporally removed from us in time? Are we intellects existing in the moment and able to control events across time and space?

I favour the "string of causal moments" theory because it gives me less headaches-unfortunately it also makes time travel unlikely.

 

[Lock Stock]

Originally posted by Cyclops
If you posit a Universe is a linear string of moments motoring along on causality (a happens & makes b happen which makes c happen) then there is a paradox with time travel, because to kill your ancestors would remove your cause. The linear string wouild break or at least radically alter, so probably it isn't possible in this kind of Universe.

Woh, slow down egg-head

 

[Falchoon]

Time travel? Any one wondered why we have never seen anyone from the future

 

[Bomber Spirit]

Logically, it would be impossible to travel back in time to before time travel was invented. So if time travel was to be invented today, people in the future could travel back in time as far as today, but no further.

 

[Stevo]

Ah, the old "grandfather" paradox.

Here's another one to ponder: Suppose that, at a party, person A tells me the funniest joke I have ever heard. I go back in time one week, with the knowledge of this joke. I tell friend B this hilarious joke. As the week passes, friend B tells other people this great joke, and these people tell the joke to other people, and so on. Eventually person A hears the joke. At the end of the week, when the moment of the party comes around again, person A tells me the joke. Where does the joke originate?

Similarly, suppose that an elderly looking person from the future suddenly appears in front of me. This person gives me the plans and means to build a time machine. It takes me 40 years to do so. When the time machine is complete, I go back in time 40 years and visit myself, giving my young self the plans and means to build a time machine. Where does the knowledge of how to build a time machine originate?

Causal loops are a rather strange conceptual phenomenon, but aren't inherently paradoxical or absurd. They seem strange because we don't understand where something first "begins".

Like Cyclops points out, perhaps our idea of time is an illusion. Indeed, this is what McTaggart argued. The sequence of events that we perceive as temporality is an illusion. The sequence of events is atemporal. One of the problems with our conceptual understanding of time is that we generally regard it as being analogous to one-dimensional space, when it in fact may not be.

 

[ScouseCat]

Originally posted by Falchoon
Time travel? Any one wondered why we have never seen anyone from the future

I was thinking exactly the same thing. Surely if time travel was possible and humans had worked out how to do it, someone fron the future would have travelled back to our time already.

 

[Stevo]

Originally posted by ScouseCat
I was thinking exactly the same thing. Surely if time travel was possible and humans had worked out how to do it, someone fron the future would have travelled back to our time already.

Perhaps the future does not exist.

There is an interesting theory called "causal set theory". Each element of the causal set is a tiny discrete element of four-dimensional space-time. These elements "multiply" and this gives us the phenomenon of time "flowing". Apparently calculations have been done which somewhat verify this theory, but I can't recall the details. It's one of the many theories floating around that hope to reconcile QM and relativity.

 

[Beffery]

My brain hurts

 

[Dan26]

The space time continuim woud be stuffed and it would cause the universe to explode. Doc Brown daid so in BTTF Part II.

So, it's true.

For what it's worth, it is possible, in theory to time travel. For example, if you travel close to the speed of light for one year, then everyone else would have aged by more than one year in that time span, even though you only aged a year. So, in effect, you have travelled into the future.

If that is reversed (and the perosn I heard this from was saying something along the lines of positive energy equalling negative energy, so anything can be reversed and everything has an opposite. Or something like that), then you could go back in time.

As a human species the level of what we know can be measured on a scale up to 100. At our current level of evolution we probably rank about a 5 on the scale up to 100, so time travel is probably something, that theoretically may be possible. One day.

 

[ScouseCat]

Originally posted by Dan26
For what it's worth, it is possible, in theory to time travel. For example, if you travel close to the speed of light for one year, then everyone else would have aged by more than one year in that time span, even though you only aged a year. So, in effect, you have travelled into the future.

If that is reversed (and the perosn I heard this from was saying something along the lines of positive energy equalling negative energy, so anything can be reversed and everything has an opposite. Or something like that), then you could go back in time.

As a human species the level of what we know can be measured on a scale up to 100. At our current level of evolution we probably rank about a 5 on the scale up to 100, so time travel is probably something, that theoretically may be possible. One day.

I'm not ruling out the possibility of time travel, but assuming the space time continuim continues on regardless, and we're all living at one particular point of that, why is it that theoretically, noone from the future has travelled back to our point in the space time continuim?? Or perhaps they have and we just haven't noticed it??

 

[Lensen]

If anyone did come back from the future, do you really think anyone would believe them? They'd be put straight into a nut house.

 

[1jasonoz]

The only groups that could afford Time Travel would be Governments(re the US). You'd think that they would have a few simple rules like don't tell anyone your a time traveller. Don't stuff up and try and change time, i.e causality(watch Red Dwarf for those who don't understand)

 

[Dan26]

Originally posted by ScouseCat
I'm not ruling out the possibility of time travel, but assuming the space time continuim continues on regardless, and we're all living at one particular point of that, why is it that theoretically, noone from the future has travelled back to our point in the space time continuim?? Or perhaps they have and we just haven't noticed it??

Think logically for a sec. Imagine that somehow, time-travel was possible. Could you imagine the ramifications if someone theoretically went backwards in time? They couldn't or wouldn't be able to physically make contact with anyone. If you stepped on a bug, it could alter something.

If time travel was theoretically possible, going back to the past would be banned. Imagine the problems it would cause.

Imagine if we had the technology to destroy comets, and asteroids and other space debris that could collide with planets and moons. What if we went back 55 million years and destroyed the comet that landed and wiped out the Dinosaurs before it hit.

What would the Earth be like now?

 

[Darky]

I want to go back to when a slab of beer cost two bucks.

 

[ScouseCat]

Originally posted by Dan26
Think logically for a sec. Imagine that somehow, time-travel was possible. Could you imagine the ramifications if someone theoretically went backwards in time? They couldn't or wouldn't be able to physically make contact with anyone. If you stepped on a bug, it could alter something.

If time travel was theoretically possible, going back to the past would be banned. Imagine the problems it would cause.

If time travel was possible in the future, don't you think people from that time would identify periods and events in history that if they could somehow prevent them from happening, their future world would be a better place?? What if their world was horrible all because of one event, like the Twin Towers being attacked, surely they'd try to prevent it from ever happening??

I couldn't imagine that travelling back in time would be banned. And what if someone travelled into the future and altered something, wouldn't that have the same kind of consequences as someone altering the past?? The only difference is, we don't know it's been altered for the better because those events are yet to happen.

 

[1jasonoz]

Originally posted by ScouseCat
If time travel was possible in the future, don't you think people from that time would identify periods and events in history that if they could somehow prevent them from happening, their future world would be a better place?? What if their world was horrible all because of one event, like the Twin Towers being attacked, surely they'd try to prevent it from ever happening??

I couldn't imagine that travelling back in time would be banned. And what if someone travelled into the future and altered something, wouldn't that have the same kind of consequences as someone altering the past?? The only difference is, we don't know it's been altered for the better because those events are yet to happen.

I think you kinda answered your first paragraph with your 2nd paragraph;

If time travel was possible in the future, don't you think people from that time would identify periods and events in history that if they could somehow prevent them from happening, their future world would be a better place??

The only difference is, we don't know it's been altered for the better because those events are yet to happen.

Who say's people haven't come back and altered some event, we wouldn't know because as you said, we wouldn't know about it, because it didn't occur, because they altered it.

 

[SonOfScray]

You couldn't really ban time travel back into history, someone would would just time travel into the future and have the law changed

How come Bill and Ted didn't stuff up history by bringing all them dudes into San Dimas but Rufus had to change the events of the past to ensure his future remained the same?

 

[X_box_X]

Back in the real world (where I come from), the population is of a 14 digit number and Gorillas rule the Earth. I was sent back through time to change the future for everyone, except, when I used the time machine, the machine blew up, as I committed an offence.

You see, where I come from, people who travelled back in time were not allowed back into the "Real Word". It is a very serious offence and I disobeyed the law. The thing is, I would be assassinated for committing this offence, however, to do that, the President of the Uruguay (the world force in the “Real World”) would need to travel back in time also, but it is impossible considering he would also commit the offence.

And, yes, for what it’s worth, the President of Uruguay is a Gorilla.

 

[X_box_X]

Originally posted by SonOfScray
You couldn't really ban time travel back into history, someone would would just time travel into the future and have the law changed

How come Bill and Ted didn't stuff up history by bringing all them dudes into San Dimas but Rufus had to change the events of the past to ensure his future remained the same?

You cannot travel into the future, because, to do that, you would firstly need to travel back in time. However, when you travel back in time, the travelling connections between the “Real World” and “this world” simply do not exist. There is no way going back into the “Real World” once you have travelled into the past. It is more advanced than that, but, simply, the time machine blows up. Hence, no way of returning back to the “Real World”.

 

[ScouseCat]

Originally posted by SonOfScray
How come Bill and Ted didn't stuff up history by bringing all them dudes into San Dimas but Rufus had to change the events of the past to ensure his future remained the same?

How do we know Bill and Ted didn't stuff up history, they never actually covered that part when all those dudes were brought back to San Dimas. We could assume that all the people would've been returned back to their original times, so perhaps the space time continuim was set where Bill and Ted said they would return all these dudes back to their time after their exam, thus noone would be the wiser because they would be returned to the instant they were taken.

As for Rufas, he had to alter events of the past to ensure his future did stay the same, because didn't an enemy from his future go back in time to change the course of history by trying to kill Bill and Ted??

 

[SonOfScray]

This is getting pretty deep! All these different theories and ideas are running around but its difficult to express.

Take Bill and Ted. They took the historical figures from the past into present time San Dimas, wouldn't the present day view of these figure have been altered by removing the people from their era of significance? All the test books would say that Napolean was 'a short, fat, dead dude who disappeared mysteriously' instead of acknowledging what would've been his actual past before Bill and Ted tampered with it!