Science Is "time travel" possible?

[Grover]

well, i watched a cool film last night (cant remember what it was called), and it made me think about if time travel was possible...

first of all: no. i dont think its possible. one reason alone makes me certaqin:

Paradox

creating a paradox could do al sorts of things:
break the laws of physics
cause the universe to stop
any other sci-fi Armageddon imaginable

imagine:

i fall over and break my arm, obviously i will want to prevent it from happening. so i go back in time and move what i fell over, so that i wouldnt have ended up with a broken arm.

but then why would i have gone back in time to move it?

another example:
i open a portal to a minute ago, looking at myself. if i shoot myself through the portal, who pulled the trigger? i couldn't have, because i died a minute before the trigger was pulled

well, thats my view, but what do you guys think?

 

[Urwumpe]

I gave you the only answer that I can give you: A loud "I don't know".

What we can exclude is time travel from the future to the past - if it would be possible on just a single day in the future, we would already observe people messing with our time line.

Possible that you could enter parallel universes by time travel that are in your present, but by the time line in the past (eg, a medieval world that is maybe even in our future, because it started later or developed slower).

There are not many physical phenomena that could possibly rely on time travel, making such claims likely. We can observe some aspects, that could have a form of time travel as explanation on a particle level.

Practically speaking, it is not impossible for us to perform a physical phenomena, that doesn't exist in nature. But it would be very hard to achieve something that doesn't happen randomly in much more energetic situations.

It is for example not impossible to explode a bomb in a forest and find a galleon afterwards. Just very very very very unlikely.

 

[RisingFury]

Time travel is most certainly possible. You're doing it right now. As you read this, you're moving slowly into the future.

 

[Pinguinboy]

I have my doubts about it.

I think travelling to the future is impossible, because there is no future yet (except 1 second ago), but I think its possible to travel back in time, but not travel back to the future. Why? Because if you are in the past, there won't be a future when you are there. So it's likely just a one-way trip.

 

[N_Molson]

"yes, but with limitations", because we are all doing that.

Now, about "jumping" forward or backwards... I'd think that backwards is going to be very difficult ; forward can probably be achieved by moving at near-relativistic velocities (take a super-spaceship, accelerate to 0.99c or so, go anywhere, stop and come back). Of course the acceleration and deceleration phases are going to take time.

 

[APDAF]

All you need for time travel is a blue phone box

 

[Artlav]

The very idea of time travel is an anthropomorphic fantasy.
Time is a product of our perception, so there is nowhere to travel to or in.

 

[garyw]

Time travel is possible. We are travelling in time right now as time marches on for all of us.

 

[Mister Mxyzptlk]

Artlav is absolutely correct.

 

[Fabri91]

Suppose time travel would be possible in a very hollywood-esque fashion.

If one moves a month into the future or the past, for example, the Earth would have moved in this time around it's orbit, and so would have the sun, and so forth.
Even moving in time for one second would see oneself "displaced" by about 30km. How comes nearly no-one thought about this?

 

[RichWall]

Time Travel and sleep connected?:zzz:

Everytime I go to sleep, then wake up and it's 8 hrs in the future.:shrug:

 

[Hlynkacg]

Of course time travel is possible. As I type this I am traveling forward in time at a rate of 1 second per second.

---------- Post added at 04:32 PM ---------- Previous post was at 04:28 PM ----------

Damn Ninja'd by Rich Wall.


The following is also a possibility...

 

[RichWall]

The short answer I think is.." Not in this universe".

If you could go back in time (Time Line Jump), it would begin a whole new reality.

The paradox is solved when one shoots himself in the past if the infinite universe theory is real.

The infinite universe theory would also accommodate causality loops.

The idea then is, if one did travel to another universe that was a Representative of ours in the past, you would still be traveling to another Place.



http://en.wikipedia.org/wiki/Schrödinger's_cat

http://images2.wikia.nocookie.net/__cb20070115103040/bttf/images/e/ea/Bttf.png

[ame]http://en.wikipedia.org/wiki/Time_paradox[/ame]

An interesting mind puzzle to play around with.

 

[Rtyh-12]

I think it can be done, but travelling to the past and killing yourself would just create a new universe where you were killed.

But that's just what I like to believe. I actually haven't got the slightest idea.

 

[Quick_Nick]

Time dilation is certainly possible, and decent for travel to the future.

 

[PeriapsisPrograde]

People tell me that time is the fourth dimension. Apparently we have a velocity and inertia in that dimension. We aren't slowing down, either. That means that no other forces are acting on us in the 4th dimension, even though the smallest of objects would cause a slight gravitational pull. Therefore, nothing else exists in the 4th dimension.

Nothing to see here...

 

[RichWall]

People tell me that time is the fourth dimension. Apparently we have a velocity and inertia in that dimension. We aren't slowing down, either. That means that no other forces are acting on us in the 4th dimension, even though the smallest of objects would cause a slight gravitational pull. Therefore, nothing else exists in the 4th dimension.

Nothing to see here...

The 4th dimension is a mathematical construct and does play apart in representing the real universe.

Just like the 5 variations of string theory converging into M theory, the math construct could lead to a more usable and insightful understanding of our reality.

There is very much a lot to see here.:thumbup:

 

[luki1997a]

Time travel is possible and arleady done.
But one thing: if you travel to the future the time will be still the same but you will be older:lol:
One of astronauts(don't remember who) has travelled few minutes(or seconds?) into the future. Why? Because of speed. Light speed(c) is ~299 792 km/s and there's no higher speed allowed in space. It's like a absolute zero in temperature: you can't get lower temp. than -272*C, in this case you can't get speed greater than ~300 000 km/s(light speed). If faster you are, then your mass is getting bigger. Also time dilation is growing up. No material body can't get light speed because:
light speed = infinite mass = infinite power needed
But! Like in thread:
speed = time dilation
Greater speed = greater time dilation
0 m/s = 1x time dilation
gravity = time dilation
greater gravity acc = lower time dilation
g=100 m/s2 = time dilation= lower than 1

Image is in polish but I'll explain it:
dylatacja = time dilation
prędkość światła c = light speed c
prędkość(tys. km/s) = velocity thousands of km/s(mega meters/s)
If you look at ship moving at 90% of light speed you will see it at 2x slowmotion. Everything inside and outside will be 2x slower, but the view of movement of ship will still be the same.
I remember I was calculating time dilation in a ship moving 5 km/s: after year it will be few minutes in future.

But read wikipedia about it I won't be explaining it here.
It's possible and arleady done and confirmed.

 

[T.Neo]

Time is a product of our perception, so there is nowhere to travel to or in.

Time merely a fantasy of human perception? What do you propose then, as the reason why things aren't all happening at once? :facepalm:

 

[luki1997a]

Time merely a fantasy of human perception? What do you propose then, as the reason why things aren't all happening at once? :facepalm:

If you travel in time at ~3x time dilation, the things on earth are not changing and the Earth's date is still the same. Only your time will change, so if you have a friend which is as old as you after time travel he will be still e.g. 20 years old, but you will be 30 years old. So, you can't travel into the future, but you can spend the time faster e.g. spend 30 years in 30 seconds(for earth observer). So, you can tell, that time is everywhere the same. For you at 4x time dilation the time will be going as fast as the earth's one, but for the observer you will be doing something 4x slower and for you the observer will be doing something 4x slower too. Why faster mean slower? That's because of:
e.g.
time dilation=2x
one second for observer on earth = 1
one second for you = 0.5
You and observer see everything in 1x motion so:
observer looking at you will see one second of your life in 0.5 seconds, because it's stretching into an one second(it's very difficult to explain it):
0.5 sec <==stretching==> 1 sec = illusion of slow motion: 0.5 seconds showed in one second(2 times slower)

So, time travel has no sense thought, because you only will get older and nothing on earth will change