Time Travel..... Is it possible?
By friendship
@friendship (2084)
Canada
May 28, 2008 10:54pm CST
I don't think so. Do you think we can travel back to the first century? It is non-sense, anyway. I don't think we can go back to the past. Otherwise, God never said about the end of time. If we can turn time back and forward, when will we reach the end of time?
However, if we go to the other planet or galaxy, time will be different. Then, I think it is possible. What is your opinion?
3 people like this
9 responses
@redyellowblackdog (10629)
• United States
29 Jul 08
I have studied the special and general theories of relativity, to include a book Einstien wrote for laymen. The short version answer to your question is that if Einstien is even close to correct with his theories, time travel backwards is impossible.
To move backward in time requires moving FASTER than the speed of light. However, as the speed of light is approached, the mass of the moving object increases toward infinity, requiring an amount of energy approaching infinity to further accelerate the object. Moving faster than the speed of light and hence moving backward in time would require more than an infinite amount of energy moving an object that had more than infinite mass. This can't be done. So, the only possible time travel is forward at the normal rate we all are aging.
1 person likes this
@redyellowblackdog (10629)
• United States
30 Jul 08
The key to what you are saying is 'massless'. I do recall not that many years ago some physicists had discovered how to apparently make some special form of light travel faster than ordinary light. This would allow the transfer of information to the past, but not any objects. There is a great idea here for a science fiction story. How about faster than light, (light) reprogramming DNA as the cause of evolution's beneficial adaptations? The possiblilities are endless.
@Uroborus (908)
• Canada
30 Jul 08
Thank you for responding, but the key to what I said was not massless. That was just one example. The other two I gave are of currently working theories where objects with mass can travel faster than light. Many physicists are working on the problem and publishing possible solution. The idea of faster-then-light travel, and therefore traveling back in time cannot just be dismissed as impossible.
1 person likes this
@Uroborus (908)
• Canada
30 Jul 08
You are absolutely correct that something with mass would require infinite energy to move at the speed of light. But relativity, either special or general, doesn't limit massless objects to move faster than light. Although it's existence hasn't been proven, the tachyon particle, does not violate relativity. It is a massless particle that in theory can travel faster than light. It hasn't been proven to exist yet, but my point is that it isn't dissalowed by any theory.
There are also some other novel possibilities for faster-than-light travel. Miguel Alcubierre, a Mexican physicist, now located at the University of Wales, has proposed a model that is remeniscent of Star Trek's 'warp drive'. His method is to alter the fabric of space, stretching it so that space contracts ahead of the ship and expands behind it. The forward effect is the opposite of the effect behind the ship, so that conservation laws are not violated. This effect has been explained using sound mathematics. The peer reviwed paper reference is "The warp drive:Hyper-fast travel within General Relativity", Class. Quant. Grav. 11: L73–L77. The journal Classical and Quantum Gravity is a well respected Journal in physics. The space contraction ahead of the ship, and expansion behind create a bubble in the middle in which the ship rides. While the distortion wave travels through space at faster than light, the ship does not move within the bubble, and so conventional time dilation does not apply. The ship essentially 'surfs' the wave.
Other theories also exist for faster than light travel. One other is the 'traversable wormhole'. These theories may not have been oproven yet, but my point is that they do not violate Relativity, so time-travel cannot just be dismissed offhand. Who knows what the future may bring.
1 person likes this
@Uroborus (908)
• Canada
29 Jul 08
It's interesting that when people talk about time travel, the assumption is always made that time travel only involves travel into the past. Travelling into the future is also a form of time travel, and is not only theoretically possible, but has been demostrated on the subatomic level. Theoretically , it can be done at our level as well. If we travel close to the speed of light, time slows down for the traveler, compared to that of the stationary observer. The effect is more pronounced the closer to the speed of light we get, but the effect is there even at modest speeds. If we travelled at 99% the speed of light, we could travel to a star 100 light years away and back to earth in just hours. When returning to earth we would only be a few hours older, but the earth will be the earth of 200 years in our future. This isn't science fiction, it comes from the theory of relativity and has been confirmed.
Now, travel into the past. No current theory allows for this type of time travel, but there is also no theory that says it's impossible. As far fetched as it may seem, we can't just dismiss it based on common sense ideas or notions about what God 'said'. That's hardly a scientific argument. The best that we could say at the moment is, no , it is not currently allowed, but such a restriction cannot be proclaimed for all time to come.
1 person likes this
@sisco100 (2338)
• United States
3 Aug 08
nope i dont its possible or will ever be. time is a man made thing to keep tack of things. if u take away time how would u know when anything happens. the universe is not bound by time and isnt govearned by it. the only time travel we can do is into the future and its one way, but its not in the way most people would thing its done. if u were to place a person in suspended animation where their body function at a slow rate then normal the u could go the future but u wouldnt be able to go back.
even if u could travel through time and change things in ur past do u really thing tht would be a smart thing to so. its like tht movie butterfly effect. if u change one thing in the past u change ur whole future like dominos all lined up. there are things tht every one would change but think about where u could be if u change tht one thing, it could have a bigger effect on ur life then u would think. for me i wish i could change things but i wouldnt want to unless it wouldnt change my future. all i can do is take those mistakes and learn form them, so i'm not repeating my past.
@jenthsenth (16)
• United States
13 Jul 08
First of all, if you are speaking in a scientific discussion, the use of God as evidence for or against something is useless. A God has not been proven under the scientific laws. Also, I believe that time travel is indeed possible. As to whether humans will attain the ability to harness it is in question by me. If the laws of relativity to indeed apply to the universe, and quite possibly if quantum laws can fit with them (into a "Theory of Everything"), all math and scientific evidence would be in favor of time travel. Also, scientists have also gained the ability via certain technologies to shoot subatomic particles into the past. Also, the end of time you are talking about.....I don't know if there is an end of time, and we have no evidence of one. However, if there is one, this does not rule out time travel, as traveling back in time would not actually extend time into the future more. You would literally be traveling back in the time of the universe. If you believe in black holes, which I am not certain of yet due to quantum physics, time travel is undeniably happening. Everything is relative outside of quantum physics, so time would be as well. If we go to another planet or galaxy, time would not be different. That makes no sense.
@jenthsenth (16)
• United States
13 Jul 08
I'm sorry, I also forgot to mention, if time is a dimension, time travel would be no different than space travel. We should indeed be able to move into the past, unless the paradox of ourselves existing at 2 points in space at one point in time would eliminate that possibility.
@friendship (2084)
• Canada
13 Jul 08
Really?? Wow! Hmmmmm..... why do we, humans, always want to exceed God? By the way, I just found this article http://www.livescience.com/technology/070307_time_travel.html -- "You Can't Travel Back in Time, Scientists Say"
@janjalanex (86)
• Philippines
13 Sep 08
Yes we can and in fact it has already been done before. If you see time as a linear model then you might be having trouble with time travel. Its simply not possible with that paradigm. Fortunately time is not linear its four dimensional. Time travel is nothing more than shifting the vibrational frequency of matter in phase with the target 'time' period.
@Destiny007 (5805)
• United States
30 May 08
I consider time to be a concept invented by man.
If God is timeless, then of what use would time be for God?
If time is merely a concept and a perceived reality instead of a physical manifestation, then it is not possible to manipulate something that does not really exist.
Therefore I don't think time travel is possible as time does not really exist outside of our perception of it's passage.
@stephcjh (38473)
• United States
29 May 08
I really don't think time travel is possible either. There is no way to actually go back in time. I think we can make things happen that used to happen back then though. I think it possible to speed time up also or change it a little bit. All countries have their own time zone, so it is very possible to spend time in one country and go to another country and spend the time there also because of the time zone difference.
@canggihadiyasa (175)
• Indonesia
29 May 08
on the theory it is possible. Einstein ever explain that theory. All you need if you want to doing time travel is speed of light. if you can reach the speed of light, you can doing time travel. on this century, I don't believe they can make it, but on the future, who knows?
You know, 500 years ago, people doesn't believe that they possible to fly and reach moon. now?
Keep dream, because without dream there's no science.
