Time travel - is it possible ?

ublinia2

What are the theorys about time travel ? is it theoritically possible ? If you travel faster than the speed of light , are you travelling into the future ?

DublinWriter

ublinia2 wrote:

What are the theorys about time travel ? is it theoritically possible ? If you travel faster than the speed of light , are you travelling into the future ?

The faster you mover, the slower time becomes relative to someone static on the ground, according to Einstein.

They tested this theory using nuclear-clocks and the Concorde in the late 80's.

If you travel faster than the speed of light, then time is supposed to reverse, but Einstein stated that nothing but electromagnetic forces can travel at the speed of light.

aidan_walsh

ublinia2 wrote:

What are the theorys about time travel ? is it theoritically possible ? If you travel faster than the speed of light , are you travelling into the future ?

Only forwards.

In fact, you're doing it right now.

Alfasudcrazy

So what does this mean? If I travel at the speed of light for lets say a week - when I come back will it be 1975 again?

In theory then I will be the same age but everyone else would be younger again.

It would be great for such things as putting the odd bet and stockmarket investing.

thedaveg

One theory of time travel involves the concept of wormholes. Imagine you have a sheet of paper which represents space-time. Draw 2 x's (X1 & X2) on either side of the page to represent 2 points in space. Imagine that it takes light 10 years to travel from X1 to X2 by travelling across the page (points are 10 light years apart). Imagine it is the year 2006 at both X1 & X2. Someone at X1 waves at someone at X2. Person at X2 will not see the wave until 2016.

Now imagine that a wormhole exists that connects X1 & X2.... can be represented by folding the page over backwards and punching a hole through the sheet so that the 2 x's touch. If someone could travel through the wormhole (BIG IF!!!!!), then they could travel from X1 to X2 in less than 10 years and see themselves waving at X2 when 2016 came around. That is time travel!!!

Wormholes are still a bit of an unknown as far as I am aware..... you'll need to speak to someone like Stephen Hawling for the latest gossip on this subject....

If you want to know more about the plausibility of time travel, I recommend a book called "How To Build A Time Machine" by Paul Davies.
For more info on wormholes, "A Brief History Of Time" by Stephen Hawling is a good start.

Chucky

I cannot but see that time travel would be IMPOSSIBLE. It is only science fiction that taints people into believing that travelling faster than light will do so.


It's funny, but the more I get into science the more I begin to reject it.

Gegerty

If man can live long enough then I think it will be possible. Maybe thousands of years in the future. Some people say it will never be possible otherwise we'd have people from the future coming back to visit us. Some wackos believe Jesus was a time traveller. There's a new theory that says it is physically impossible to change anything that would alter the future. "what if i went back and killed my grandfather, then I would never exist so how did I go back and kill him in the first place?" This paradox is sorted by saying its just physically impossible to do it. Some, as yet, unknown force would stop you.

Son Goku

Chucky wrote:

It's funny, but the more I get into science the more I begin to reject it.

Based on what?

Chucky

Sorry, 'rejecting' is the wrong word and I shouldn't be posting in this thread for my views are skewed due to depression.

Science is very interesting but all I can see is that it will be no use to us once all of the stars have burnt out. In that sense, I can offer no productive input to this thread. Sorry

Unstoppable PoO

I think it is as it is merely another dimension in space like the other 11, perhaps though we have not mastered it because of chuck norris and I quote:

"Light's amplification in dark matter can easily cause a quick condensation of time."

End Quote

netwhizkid

Time Travel is possible (but not for humans for another few years) and it has me intrigued this afternoon. Yesterday evening I was watching Discovery Science and the was a programme on called "The Worlds first time machine" It will work in theory and all it is lacking is funding. Ronald Mallet was the guy on it and his theories will work providing Einstein was right. If he can get it built he will be able to send protons and I think neutrons back in time and equally into the future. If he can do this it will be the greatest change ever for humanity. All he would have to do is build it and let say he grandson or some other genius in the future send back the instructions on how to build a better version.

It sounds mad and Tin-foily but if it is achieved it will be the impetus that will change peoples outlook on life forever. I lay in bed this morning at 6am struggling to breathe with an Asthma attack and then the programme almost sent a message to me if achieved it could possibly cure my asthma using technology invented maybe eons from now. All we would have to do when building the machine is leave instructions on what we want sent back. The grandfather paradox would not apply either as there are infinite universes. I am probably somewhere else now having a shower or playing golf. Growing up on a diet of Superman, Sliders and Back to the Future. I feel like a kid in a candy shop at the prospects. It undoubtedly would cure Aids, Global Warming, Cancer etc. People could probably live forever as a result of it. The machine that he plans to build would be more like a telephone line to the future rather than a Delorean. And cannot access the past i.e. if it was built today he could not visit last week. But with the technology being sent from the future all that would be possible.

I for one will be following this closely.

Dathai

netwhizkid wrote:

All he would have to do is build it and let say he grandson or some other genius in the future send back the instructions on how to build a better version.

I for one will be following this closely.

If time travel was possible, wouldnt you think someone would have come back and said that it was possible?And given instructions on how to build it?

Son Goku

Dathai wrote:

If time travel was possible, wouldnt you think someone would have come back and said that it was possible?And given instructions on how to build it?

Is that how a time machine would work?
GR suggests that if you can build one it can only take you to moments where the machine existed.

Gegerty

netwhizkid wrote:

Time Travel is possible (but not for humans for another few years) and it has me intrigued this afternoon. Yesterday evening I was watching Discovery Science and the was a programme on called "The Worlds first time machine" It will work in theory and all it is lacking is funding. Ronald Mallet was the guy on it and his theories will work providing Einstein was right. If he can get it built he will be able to send protons and I think neutrons back in time and equally into the future. If he can do this it will be the greatest change ever for humanity. All he would have to do is build it and let say he grandson or some other genius in the future send back the instructions on how to build a better version.

It sounds mad and Tin-foily but if it is achieved it will be the impetus that will change peoples outlook on life forever. I lay in bed this morning at 6am struggling to breathe with an Asthma attack and then the programme almost sent a message to me if achieved it could possibly cure my asthma using technology invented maybe eons from now. All we would have to do when building the machine is leave instructions on what we want sent back. The grandfather paradox would not apply either as there are infinite universes. I am probably somewhere else now having a shower or playing golf. Growing up on a diet of Superman, Sliders and Back to the Future. I feel like a kid in a candy shop at the prospects. It undoubtedly would cure Aids, Global Warming, Cancer etc. People could probably live forever as a result of it. The machine that he plans to build would be more like a telephone line to the future rather than a Delorean. And cannot access the past i.e. if it was built today he could not visit last week. But with the technology being sent from the future all that would be possible.

I for one will be following this closely.

Checking the date of your post....yes you were indeed watching this program on April fools day

Gegerty

Dathai wrote:

If time travel was possible, wouldnt you think someone would have come back and said that it was possible?And given instructions on how to build it?

Some scientists believe there is a force that prevents time travellers from doing anything to alter the course of the future. You can observe but not interact, it will be physically impossible.

If they did come back and tell us how to build it then it would never get invented in the first place and hence they could not go back in time and tell us how to invent it.....it would be physically impossible to do.

Raiser

I'm actually posting this from the year 2009.

I can now inform you all that the threat of Avian flu was eventually surpassed by mixing large quantities of Lemsip with even larger quantities of Trill bird food and dropping it all over the earths surface via multiple space shuttles.

If you have any questions please forward them on, I'll answer them when I can.

Edit 16/12/2009

*** Please stop sending personal messages requesting for Lotto/Euromillions winning numbers ***

Talliesin

netwhizkid wrote:

Time Travel is possible (but not for humans for another few years)

Pfft. A few years. I built one next thursday.

Tar.Aldarion

I had a nice meal next thursday.

Is that how a time machine would work?
GR suggests that if you can build one it can only take you to moments where the machine existed.

I have wondered about that a lot.
Also, about a possible Stephen King's - The Langoliers past.
Time travel is one of my favourite things to think and read about, well that, quantum mechanics and black holes.
I'm not exactly making any breakthroughs though.

legologic

Well technically it could be possible. A fairly limited time-machine can be built but you need a couple of rather hard-to-find thingamybobs.

Ingredients:
1) A traversable stable macroscopic wormhole
2) Some method of moving the opening of said wormhole
3) A very very VERY fast spaceship (99.9999999999999% of the speed of light would be preferable)
4) An incredible sense of self belief
5) A big cigar!

Instructions:
Jump into yer space ship and put the wormhole in the back. Now, take off and fly around at close to the speed of light for a few hours/days/seconds whatever takes yer fancy. Now stop. Take your wormhole outta the back and have a peek through. Time should've moved slower for you than for the people on the other side (i.e. they're in the future). Get them to throw tomorrows lottery numbers through on a piece of paper. Light your cigar... you've just built a time machine!

Gegerty

8.21 Gigawatts!!!!!

legologic

Gegarty wrote:

8.21 Gigawatts!!!!!

It's what makes time travel possible

vinks

if i remember right from my quantum mechanics and hepp classes, negative time (or rather going back in time as people seem to call it) is mathematically possible.

but the issue is, if you are to accept negative time, it gives rise to negative space and negative gravity (from the relativistic versions of equations of motion), i think the issue is how do you deal with complex numbers and how undecided it is. it becomes difficult to prove soundly and to top it all off there is almost no physical evidence that its possible to have negative gravity.

when was the last time you saw gravity repel instead of attract? have there been physical observations of gravity repelling?