Can a time machine be REALISTICALLY built by humans?
138504
not technically in the way we know it. According to Einstein time as the measure of distance in the figurative Universe can be turned back by exceeding a speed of the speed of light squared times the mass of the components at this speed. Read steven Hawking a history of time to learn further on the subject. Time in terms of the chemical equation, namely reactants to products can be reversed by this step. However, in respect to redoing certain moments in life, no. The only force which can do that is God.
70282
No.  You'd need to have a wormhole.  Current theory predicts that transversable wormholes exist but would not allow time travel.  See reference for details.
1027001
I do not believe that a world as beautiful and ordered as we have could possibly come about by chance. If you take all the pieces of a watch, stick them in your pocket, and jump around for a few billion years, I can guarantee you you won't have a spontaneous explosion in your pocket and pull out a running watch. And creation is so much more complex than a watch.
609407
Well i don't think it is possible....but if it is created it will be great...but the cost will be very high...many unsolved mysteries would be solved...hope someone invents it.. ;)
507453
Yes.  The human mind is just an incredibly complex computer which can manufacture it's own connections.  All we need to do is get the software and hardware sides of our current technology up to the level of our brains and beyond...  Easier said than done, I know.
186287
Under Einstein's General and special theories of relativity, time travel is considered possible. Stephen Hawking has speculated that it must not have been discovered to be practical as we have not seen tourists coming from the future to visit us.
969010
What a debatable query! Very much suited to my interests. :)\n\n            First things first. Doorman proposed a fabrication that amused me. My beloved, time can bear itself in energy, yet memory hold itself solitary in such consideration. Memory is another term one is to consider in terms of biological structures, not energy. Were time to store itself in such energy one to explode by the time they get old XP. Yet your proposition holds itself true in one aspect. We forget. Like we lose energy. Yet memory holds itself in alliance to life, an indescribable, unphysical term.\n\n            Now for my proposal. We bear to our knowledge the sphere of our vision. What we see, we believe. Yet we go on FORWARD in time. Like a fluid. Space-Time-Continuum...\n\n            In accordance to one of Einstein's theory, the time holds itself in a stretch of another dimension all together. We know so much of time, yet in reality we know N-O-T-H-I-N-G.\n\n           Ask me why? The answer bears itself in utmost simplicity. We can only conclude on matters we are able perceive in correct mannerism. We do not bear such a sense organ nor are we able to implement over 4% of our brain, so as to perceive the concept of time in proper ideology. Therefore we cannot forge a concept concrete enough to bear the yoke of your question.\n\n          Yet we can ALWAYS speculate! In such speculations, we can come to many ways to rewind time. Suppose time IS a fabric. A vast expanse of infinite non-molecular material. If we are to possess a way to make a cut in this fabric, we can gain access to two different periods in time.\n\n          Now here's the boomer. What if time DOES repeat itself? Now stick to me while I take you to a psycho flight. Seatbelts on? good.\n\n         So far we have considered time to be a concept in whose relation we all exist. Now imagine this. WHAT if time is relative to every individual? No-one has been able to explain the term 'life'. Maybe this is because life IS time? What we consider time is the fabruication of us mortals. What if time exists independently for everyone? When one perishes, he is actually going to REPEAT his so called 'life'. Perhaps he period from the Big Bang to the collapse of the universe has repeated itself millions of times already!\n\n             Now thats a speculation. No-one can state it correct or incorrect, for one doesnot bear such perception. Perhaps we are just the play-stuff of a larger colossal existence. Then again, what is existence?
474378
Ahh an inventor that wants to become rich... Definatley a time machine so I could go back and fix my mistakes, or a "beam me up scotty teleporter". That most probabley wont help you, but thats what I think would be cool. Heidi
885178
Research suggests that within the next century not only will we completely understand the human brain but computer processing power will far exceed it. Therefore we should not only be able to replicate the brain but should be able to create a far superior machine or human version 2. Depending on how we as humans merge with this new technology will determine whether we are part of this superior race or seen in the future as a lesser being. Either way endless and exciting possibilities are around the corner I don't think we will be waiting 1000's or even 100's of years.
1105020
Possibly although Stephen Hawking once said that if time travel existed, we would see plenty of tourists from the future already and we would have historic accounts of them. There are plenty of theories of how it could work but no definitive solution has been developed.
1156662
No we cannot. The time travel stories are our over enthusiastic mind's work. It just cannot be possible. Unless we attain speed of light. Do u believe in relativity? think about it... maybe u will find answers there.
386834
Well in all simplicity, if that were fact then yes it would be conclusive proof.  But can you state that we have never encountered a time traveler with any margin of accuracy?  I think not.  If technology ever reached the point of time travel, there is good reason to believe that philosophy and laws of that time period would dictate how our future friends would carefully act in their past (our present).  The same laws (along with technology) would also, most likely, prevent folks from misusing time-travel technology.\nAlso, I don't think we can accurately predict what sort of effects it would have on non-time travelers.  (I mean, you and me, the people who don't "go anywhere" in time)  Who knows weather we time-bound folk would have any way of perceiving the effects a time-traveler would have on the time line?
1042619
Well, it is a fantastic concept! Also, even if this could happen, it would take billions, if not billions of years!\nAnother way is that who and why do we accept the time direction as we do now? Because it fits, us! Well, sometimes this concept is reversed! SO, time could go the other way or go faster or slower, but this only in certain moments, yet!
1128700
My first answer is probably not, because we would see future people by now.\n\nHowever, what if UFO's are time machines from the future?
218567
There is no "close." You either have perpetual motion or you don't. Because any device you can come up with will have energy loss due to heat lost by the work done, you can never have a physical device that will keep going without additional energy. There is a theoretical particle that can never go slower than the speed of light, which I guess would be a form of perpetual motion, but it is not man-made.
48034
Of the three, I would say a dream viewer would be the most tangible.  Science is constantly making advances in neurology.  Time machines and teleportation devices would both defy laws of science.  Time travel itself would be a form of teleportation.  Would you want to trust a machine to reassemble your atomic/molecular structure?  I also would consider impossible for a machine to transport the human soul.
303837
Time travel is possible when we travel forward not backward. IF you look to the history books there are no such thing of human come form the future. So that is the proof that has defined the theory that we can't go to the past. There are theory that we can move forward by using the method of speed. Once you increase the speed of travelling the time will change very fast, and you might be in the future. But to have that kind of machine to bring you forward needs a lot of discovery especially about the strenght of metal, fuel, speed, and a lots more. You can get the theory about speed from einstein. Whatever you want to know about it, you can get it there, BUT eventhough you learn about time travel, you won't get that technology while you still alive. Maybe you can use that information just for you knowledge. Not more than that.