Is time travel possible?

Question

can you help me be enlightened on this one

Answer 1

I am by no means an expert on the subject. Time travel and space is just a hobby of mine. But according to current theories and speculations time travel *is* in fact possible. Let me try to explain how. I know it's long but I've tried to keep it as interesting as possible so do read on. And btw, my carpal tunnel syndrome thanks you for its existence.

Please check out this excellent article for more detail: http://science.howstuffworks.com/time-tr...

Okay, first of all you need to understand what space and time are. Space is what we move through. It is what matter exists in. The x-y-z axes are all part of space. Time is, according to the theories, *another* dimension to space. It is like the 4th dimension, kinda like x-y-z + something extra.

Now because we consider time as another dimension, it is therefore linked with space. So, if you move an object from say, in front of your face to on top of your head, you are moving that object through space AND time. Thus space and time are linked and hence we get the "spacetime continuum". The spacetime continuum... oooo.... sounds fancy and complicated! It's not that complicated really :D

Anyway, back to time travel. So... now we know time is another dimension - the question is *how* can we travel through time. There are currently 3 different primary theories:

1. Travel at light speed

2. Wormholes

3. Cosmic strings.

1. Travel at light speed:

According to our buddy Mr. Einstein, when an object comes close to or moves at the speed of light, it *slows down*. Pretty cool huh? In other words, it is moving through *time* at a slower rate than the rest of the non-light-speed-moving objects around it are. Therefore, it would age slower. So, if we could put, say... um... you or a dog or something into some container and whiz it at the speed of light for say 20 mins, it would have (i.e. you would have) aged slower than the rest of us. Therefore, for example, you age only 20 minutes while the rest of age 20 years (just an example). So, in effect, you have travelled into the future by almost 20 years.

2. Wormholes: Okay, let me try to sum up what a worm hole is. Mr. Einstein (again) said that when an object just exists in space it puts a dent in it, so much so that it affects objects close to it too. To visualise this, imagine 2 people holding a bed-sheet by the corners very tautly. The sheet represents space. Now take a tennis ball and gently place it on the sheet. After it's rolled around a while, it settles somewhere and puts a dent in the sheet. Now imagine a 2nd ball placed on the sheet. If its smaller than the 1st ball, it will roll around and eventually reach the 1st ball (btw, this explains gravity too and why mother earth rotates around the sun and *not* vice versa).

So, we've established this theory (forgot the bugger's name though - sorry). Now, worm holes are basically like tunnels that are like shortcuts through space. Visualise a sheet of A4 paper. Now bend it into 2 *without* creasing the center - see the link at the start of this for a visual explanation. Now imagine a hole on the top (representing earth) and a hole directly below - this represents somewhere else in the universe - a place far.. far.. away. Anyway, the worm hole is basically the tunnel in between the 2 holes - instead of conventional space travel, where we'd have to go all the way across the paper (i.e. space) to get to the other point, we just jump in one end of the hole and appear on the other. Pretty nifty huh?

Anyway, back to time travel. Imagine if we could make a worm hole. Then we keep one end here on earth with say Mr. A and put the other end on a space ship and fire it up into space and make it travel at the speed of light with Mr. B. Now while B's end is travelling at speed of light, A's end is not. Therefore, B's end will be aging *slower* than A's end. So, after say 20 mins (in B's time), Mr. A would have aged 20 years while Mr. B only 20 mins.

Now let's say Mr. A jumped into his end. He would end up in the spaceship with Mr. B and would have travelled into the future. But CHECK THIS OUT: if Mr. *B* jumped into his end, he would end up back on earth with Mr. A and he would have travelled back into the *past*. Freaking amazing (in theory)!

3. Cosmic strings: Just think of these things as pure gravity. Enough gravity to suck anything into them. MUCH more powerful than black holes even. The theory is, take 2 of these babies and tie them together - the centrifugal force created would be enough to propel anything close by to or even faster than the speed of light. If you don't know centrifugal force, think of a merry-go-round. It's just the force that you feel when you're moving fast on the thing. Try it and see - doesn't it feel like you will be thrown from the go-round if you let go? Now imagine something almost a trillion x billion times more powerful - imagine how fast you can fly then! Fast enough to make you slow time and travel into the future.

Answer 2

No and never will be.

Answer 3

dude, haven't you ever seen Back to the Future?  Of course it's possible.

Answer 4

yeah totally. I do it all the time :)

Hope this helped!

Answer 5

Potentially, yes. In the event that some sort of slipstream-esqu travel is discovered, it would be possible to travel faster than the speed of light relative to our (4) dimensions (while still going at sub-lightspeed across all dimensions) this would allow for time travel. However, it is doubtful that such a method is possible.

Answer 6

no

.

Answer 7

not currently.  Furthermore, I assume that in the future it will not be possible to travel to the past.  If it were possible, then someone from the future would already have gone to his past (our present) and we would know the answer.  

Answer 8

No,never.  Time travel includes going back in time which in its turn is only possible if we can travel greater than d speed of light which is impossible since speed of light is d maximum speed anything can achieve in this universe

Answer 9

yes

you are traveling through time right now.

Answer 10

Einstein's theory of Special Relativity states that at any given moment (if "moment" is the right word to use here) an object is travelling in all four dimensions at the speed of light. So when we are stationary, time elapses the fastest, and as our velocity increases in space, time is slower for us.

So in a way, yes. By travelling at a velocity close to the speed of light, time slows down for you, so were you to live on a spaceship travelling close to the speed of light for, let's say, thirty years, by the time you get back on Earth, everyone will seem to have been older by more than thirty years.

Note that this only allows travelling into the future. Travelling back in time, obviously, would require a negative velocity in the dimension of time, or a velocity in the dimension of time higher than the speed of light. And according to known physics, this is impossible, because as you approach the speed of light, you require exponential amounts of energy for acceleration (since your mass increases).

Answer 11

Not at the moment.  There seems to be no record of anyone appearing from another time to visit us in our time so I imagine that in reality the whole thing is unlikely to happen.