Cover Image: September 2002 Scientific American Magazine See Inside

How to Build a Time Machine [Preview]

It wouldn't be easy, but it might be possible















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WORMHOLE GENERATOR/TOWING MACHINE is imagined by futurist artist Peter Bollinger.

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WORMHOLE GENERATOR/TOWING MACHINE is imagined by futurist artist Peter Bollinger. This painting depicts a gigantic space-based particle accelerator that is capable of creating, enlarging and moving wormholes for use as time machines.

OVERVIEW
  • Traveling forward in time is easy enough. If you move close to the speed of light or sit in a strong gravitational field, you experience time more slowly than other people do--another way of saying that you travel into their future.


  • Traveling into the past is rather trickier. Relativity theory allows it in certain spacetime configurations: a rotating universe, a rotating cylinder and, most famously, a wormhole--a tunnel through space and time.
  • Image: PETER BOLLINGER

    Time travel has been a popular science-fiction theme since H. G. Wells wrote his celebrated novel The Time Machine in 1895. But can it really be done? Is it possible to build a machine that would transport a human being into the past or future?

    For decades, time travel lay beyond the fringe of respectable science. In recent years, however, the topic has become something of a cottage industry among theoretical physicists. The motivation has been partly recreational--time travel is fun to think about. But this research has a serious side, too. Understanding the relation between cause and effect is a key part of attempts to construct a unified theory of physics. If unrestricted time travel were possible, even in principle, the nature of such a unified theory could be drastically affected.


    This article was originally published with the title How to Build a Time Machine.



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    1. 1. manoj sharma 05:11 AM 11/19/07

      the theory of time machine is quit interesting but i see there are some loop holes in it as time travel to past and future can have amazing consequences .

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    2. 2. sagar123 04:59 PM 12/5/07

      how can we create the twisting of the space. so we can place an object on it and make it exceed the speed of light

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    3. 3. ninjasurfer 02:19 PM 12/6/07

      If I had a time machine I would marry Edgar Allen Poe. Or Jesus.

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    4. 4. astroguru 05:11 PM 12/8/07

      Time machine is very much possible.

      That time is very much near when people will travel back in time and forward in time.

      I know when this could be possible,

      Just wait and watch.....
      ..... astroman

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    5. 5. kshitij shravan 03:44 PM 12/11/07

      yes i belive that time traveling is possible since i was a child,but the relation between intial mass and mass at some velocity, simiarly time, and length contradicts my mind.due to atmospheric friction it is not possible to achieve such a great speed.

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    6. 6. lebedkat 08:59 PM 12/12/07

      I would travel in the past to save my daughter!!!!!

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    7. 7. Neibaangami 04:14 PM 12/15/07

      i believe light is the only source for time travel!!!

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    8. 8. smuthu2004 07:20 AM 12/16/07

      in the article it is mentioned if i go bac ten years in the past my mom willbe ten yrs younger..in that case even i should b younger right...by selva

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    9. 9. shivkumar 09:33 AM 12/18/07

      it is possible only if we change the time period as per our requirement. is it posssible?

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    10. 10. GURUPRASAD 01:00 PM 12/31/07

      to built a time machine one has to modify second law of thermodynamics.because we know that as entropy of universe is always increase;

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    11. 11. mr.epoch 03:28 PM 1/1/08

      i am a 39 yr old man, who has been fascinate by time tral since i was 12. by my calculations only traveling forward in time is possible. as you cannot travel back to what is no longer there.

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    12. 12. SeanDeneau 12:48 AM 1/2/08

      I am trying to figure out how to build a time machine who wants to help me and become rich or Famous Contact me SeanDeneau@Yahoo.com I am in MN Email me ASAP It is Possible to do it so lets do this together lets be rich and famous together I am so serious we could be scientists of the Year, or a Lifetime I am not crazy I am Serious

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    13. 13. Gkeys55 06:45 PM 1/2/08

      I Wish I knew!Would love to help!
      Gkeys55@aol.com

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    14. 14. Gkeys55 06:58 PM 1/2/08

      I would love to be a traveler like you see on TV with the show journey man.I wish there were such A JOB!

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    15. 15. Louisemab 07:56 PM 1/2/08

      One question: Even if you succeed in departing successfully, what is going to 'receive' you on the other side?
      Another question: Is te past 'stable', i.e. is it really a 'place' that you can travel to. And what about the future?

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    16. 16. gagankhaira 05:14 AM 1/10/08

      althogh it seems 2 b possible 2 build a time machine. yet it hav some loop holes.what if i travel in the past and kill the man who build that machine.in that case will i b able 2 travel back in past

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    17. 17. thefuture 12:28 PM 1/13/08

      I beliveve time travel is possible so why not make it happen...... 4 words.......
      "Back To The Future".... Possible......Very Possible.....

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    18. 18. RAJESH 09:04 AM 1/24/08

      as far as i know, time travel is very much possible after knowing time is not absolute. But i thing v can b able to c d events but not able to interept them

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    19. 19. forgotten 02:12 PM 1/27/08

      time travel is just confusing..
      pls note time is created by humans...a wormhole..
      u already r travelling...
      wake up...

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    20. 20. RAJESH 05:56 AM 1/28/08

      i also think time machine is no more impossible,

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    21. 21. izxuwon 09:21 PM 1/30/08

      maybe if u chang the wind like wich direction its going in it will turn the way earth is spinning and it will make a worm hole going back in time and yul be able to stop it where you want to stop

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    22. 22. Quantumystic 08:04 PM 1/31/08

      Interesting...scientists have always scorned the theory of time travel but recently it has become plausible that sometime in the future, such a machine will be constructed.

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    23. 23. Soroush 02:12 PM 2/26/08

      In my opinion to travel through the time is possible.As far as time is human thought.For us it has begining point but no ending.But if we look at it higher then human's mind (for e.g as a creator or the God),time practically does not exist.Just imagine if we could go to the past and change something and return to the peresent time,evry thing we had done befor our journey will be subtitute by the new thing we did and atually we do not have access to the last information in our memories.I belive that the past and the future is always in the progress and maybe some one could have an experience to go to the past or future and change some thing,but the probmlem is that no one is not able to remember it.Because our mind and generally we are time limited.

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    24. 24. C.J. Hall 03:18 AM 3/5/08

      Question.
      If one were to event a working Time Machine would they follow the Earth forward or backward through space?
      Or would they remain fixed in space and watch the Earth and other celestial bodies simply drift away?
      C.J.

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    25. 25. azharkhan 10:31 PM 3/20/08

      Ok we would one day...travel with the speed of light. And go say 500 years forth. The Question z...Would there be living if not the generation of those people living today....Hey not 500...say A week into future..would we be present...there and the one watching his own future. which are actually living 7 days back...it meanz we have got duplicates...like in The Matrix....thats something unusual. say if u finish a living thing in those forth 7 dayz might vanish 7 dayz back....u return back and say that i have killed u 7 days ahead...funny...

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    26. 26. chandan sinha 01:50 PM 5/20/08

      i will make the time machine

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    27. 27. ankit29 08:35 AM 6/1/08

      time travel is ok as long as you are continuing to move with the speed of light..what will happen when stop doing so?
      you will fall into the same time frame again..only your age with respect to the outer world will differ...how can THIS be called time-travelling..isnt it just an illusion??

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    28. 28. agent0 07:59 PM 7/9/08

      I have traveled in time. I was able to alter the course of my familys loss in the 1929 stock market crash by warning my grandfather. Money from that endevor has been used to further research time travel. Recent trips included altering the course of the second world war making it possible for the allies to win. In real time Japan and Germany conquered the world which then resulted in a third conflict between Japan and Germany which included the atom bomb and millions dead. I have wrestled with my thoughts and returning to reverse the course of the Bush presidency. Other than those incidents...I have used time travel more as a way of looking back in time.

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    29. 29. kwin 11:04 PM 7/10/08

      We should design a hydrogen car or a magnetic motor that can vault us into the future, then we could dream of time travel.

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    30. 30. hallwills 04:09 AM 7/21/08

      i think time machine is possible only for machine not for humans,once when the time is gone there is no way to regain it .we can travel to future but it is impossible to comming back to past.

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    31. 31. hallwills 04:15 AM 7/21/08

      When we are speaking about time machine, it is attainable , there is a possiblity for traveling to future.from my point of view there is no way to travel back to future.Because each and every time the time is running. there is no way to stop the time.

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    32. 32. TimeMan=wormhole in reply to agent0 05:11 PM 7/23/08

      Is time travel possible or just a fantasy we want to believe in? I think it could be possible all the basic aquirements is a termal generater,flux capacity,.... These are the things that may be the parts to make a Tme -machine the rest i need more reseach on... I need help to build 1, so can ou help me assemble such an ark? I need a crew and funding please email me back. My intentions are for the greater good and i believe that says it all.

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    33. 33. TimeMan=wormhole 05:13 PM 7/23/08

      Email is ajalecmunoz@hotmail.com

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    34. 34. sandybiet 02:44 AM 7/25/08

      in my view the space-time doesnt curve its the presence of ether or dark energy which is compressed by gravity and causes the curve pah of light

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    35. 35. CorbinzRize 04:51 AM 7/28/08

      Time travel is very possible, but not with light ,but as the speed of light is the key. If one could create a vibration that vibrates at or faster than the speed of light and control the time that it is allowed to vibrate and make a measurement, we would in a sense be able to control it. If you use a car alternator and hook it up to a pizo electric crystal and then controlled the vibration that the crystal was making you would be able to slow down time and even reverse it.. You could use a tuner for example to control the vibration. The problem then comes in is how big of an area is affected by this disruption of time. The easy fix would to use a stronger power source, creating a bigger magnetic field in which will create the bubble for which anthing in that bubble will be affected by the action. All of this would have to be measured as to get a good measurement so to go to and from the times one would select. A welding machine has similar capabilities as they create an emensce ,agnetic field and also can control the pulse at which the electric current is fuxuating. Ad a pizo electric crystal of sizable means and bam you have a time machine.

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    36. 36. Joshy333 in reply to CorbinzRize 05:14 PM 7/28/08

      Yes and it would have to be one BIG crystal at that. You would have to cause a large enough vibration to travel as fast as you needed to, then also you run into the problem of matter destabilization, more than likely, you'd just dissintegrate. Sorry, but good theory.

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    37. 37. CorbinzRize in reply to Joshy333 10:16 PM 7/28/08

      Awesome response . My Name is Josh as well. You have some insight on the very possible ideas that i have thought about. It would be nice to talk more on this and more subjects as it is a very wonderful and interesting field of study. I plan to be a Quantum Physist, in the years to come , but for now I am working my way up to that point.
      The vibration would be contained in the crystal as it has it's own containment, but the crystal may not be able to contain the vibration so it would be the one that would decinergrate, but there could be a crystal that could be made to withstand the abuse and be used in it's place with extra precautions such as containment fields and chambers.

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    38. 38. bluray93 05:17 AM 8/9/08

      2 build 1-either figure out da 6th dimension
      Be an amazin intentor and travel faster than light(impossible 2n extent as mass increases)
      Another option is black hole it may b on earth on bermuda tirangle or on space
      Take risks or think hard 2build1
      Wen u succeed don 4get 2 go bak in past in 1954 and get einstein n accomplish his dreams (1yr before he died:)
      Explain him string theory and b his friend
      If u have doubts email me on bluray93@gmail.com
      M plannin 2 intent 1
      Remember impossible's nothing!

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    39. 39. dale 01:50 PM 8/16/08

      i have travelled back into the past,couldnt tell you what year but it seemed like between 1930s and 1940s.thats what the cars looked like to me and the clothes it was only for a split 10 seconds but it was amazing told a few people but they thought it was a joke so i kept it queit.it happened when i was 15 im now 38.

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    40. 40. dale 01:56 PM 8/16/08

      i travelled back in time when i was sixteen im now 38,it was for a split 10seconds but it was amazing,i need to speak to someone about my experience to see if they understand what happened to me,i think it was in the 1930s 0r 40s judging by the cars and clothes but i couldnt move but i could here and see.

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    41. 41. bobbers 10:54 PM 8/20/08

      i think that it can be possibleif you knowwhat to do.

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    42. 42. bobbers 11:07 PM 8/20/08

      the main thing you need to make a time machine is the speed of light and lots and lots of energy.

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    43. 43. shaggadelic 03:55 PM 10/5/08

      i would travel back to bust my step-brother!!!!!!!!!!!!!!!!

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    44. 44. blu 07:20 AM 12/18/08

      1ce its invented make sure u get einstein back2da future he can also help us on da hadron collider experiment...mak him also meet hawking 4discussions.....
      accordin2theory of relatvity if ur near som black hole in space or @som place were time slows down 4 somdays and u go bak2earth ull be in da future
      simple physics -wen time is slow4u and normal speed@earth ;days 4u ll becum yrs4earth.............so wottu waitin4..........

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    45. 45. phayez 12:27 AM 12/27/08

      Before the blogs were canceled here on Sci Am I had a blog under the username "PHAYEZ" which dealt with, among other things, time and measurement. I put forward that time only exists as a feature of three dimensional existence. Time is the "velocity/distance of 3D matter relative to the velocity/distance of other 3D matter". Outside of three dimensions "TIME" as such does not exist and infinity is equal to zero "time". Also outside of three dimensions measurements cannot be made of anything which makes mathematics, with all due respect, irrelevant since the language of mathematics has, as a syntax, products of measurement. The existence and non-existence of time is a spatial relationship oxymoron which is difficult to grasp when you are an entity who is wholly dependent on being made up of atoms which are moving through space.
      One final comment, if I may, on the speed limit of light and the fact that even information cannot exceed the speed of light. At the speed of light time is zero, in other words for the light there is no time that passes so that regardless of where it arrives, it arrives instantaneously. Nothing can move faster than instantaneously, even information...
      Pierre
      username: PHAYEZ (Edmonton,Alberta,Canada)

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    46. 46. voicecapsule 02:38 PM 1/30/09

      I just created my own time machine, it just goes one way for now. please see it at http://voicecapsule.com

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    47. 47. voicecapsule 02:39 PM 1/30/09

      I just built my own time machine, for now it just goes on way. check it out at http://voicecapsule.com

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    48. 48. Derk13 12:02 PM 2/11/09

      But does it really work to go from the current to the future or past By: Derk13

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    49. 49. tufast1112 11:33 AM 4/28/09

      It's about time? who would want to do that time travel any ways? i know how to make time travel, how? throw a clock.

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    50. 50. tufast1112 11:35 AM 4/28/09

      So were going to manupulate the molecules? to reverse time? umm? even tho time is an illiution how can you receve an answer to something thats not there?

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    51. 51. tufast1112 in reply to tufast1112 11:39 AM 4/28/09

      you guys? i can manupulate time!

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    52. 52. tylerangel666 02:28 AM 9/12/09


      I would like to bring up some issues I have with the current fiction of Time-travel. Im not doing this out of some sort of Hum-bug mentality. There are just certain details that have not been taken into account.

      First is the idea that you can go back in time a single day and end up in the exact same place you traveled from. The Earth isnt stationary. Whether youre talking about its rotational spin on its own axis, or its rotation around the Sun, its never in the same place day to day, or hour to hour.

      My theory on that is, you can only travel back in time, or forward in time, in 365.25 day increments. 365.25 days to take into account the leap year. If you want go back in time to a certain date, youll have to go back a full year plus .25 days, and wait for that date to arrive. The only other alternative would be to travel day to day in an orbiting vehicle and go through a re-entry scenario. For anything around a six month period, you would need a true space craft and travel from the other side of the Sun. That seems like the reality of it to me.

      Second, when we think of Time Machines, we should be thinking of something on the scale of the Space Shuttle, not a small capsule. A Shuttle-size spacecraft with a detachable module for re-entry. But then once we get there, how do we get back? We would need the same amount of energy on the other end, in order to get back. We would have to first time-shift an energy supply. The best way to do this would be to send it back far enough in time, and to put it in a place where no one would know it was there. It would sit there until we needed it. Unless of course the theoretical concept that we wouldnt be effecting our own time-line is correct . Then we could just place it anywhere not caring if our other Quantum possibilities knew about it was there.

      I realize that Time-travel is far off. I also realize that if it is to ever come to fruition, there are many other factors to take into consideration. We cant just push a button and go back a bit to tell ourselves to take a right instead of a left. Or go up instead of down. So if anything, all Ive done is figure out that Time-travel is going to be far more expensive than we thought.

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    53. 53. SREEKANTHMS 09:36 AM 10/29/09

      i need to TT

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    54. 54. terrybob 06:21 AM 11/17/09

      if i had a time machine i would go back in time and fix all the bad things I've done to people.

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    55. 55. terrybob 06:22 AM 11/17/09

      if i had a time machine i would go back in time and fix all the bad things I've done to people.

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    56. 56. levcoleman 09:58 PM 11/17/09

      it has already happen you know when you have dejavu well that is the effects of time traving. and when you have dreams then they come true it is the effects of time traving. the govenment has tried covering things like that to prevent time worp warm hole.

      JLC

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    57. 57. Phoenix85 07:35 PM 3/9/10

      Building a time machine is very easy and may have already been done. Inside the human brain is a tiny gland, called the pineal gland, which is a gate way for hyper dimensional travel (the ability to access time space). When the Pineal gland is reverse engineered into mechanical form (surprisingly easy), a time machine is created. I would suggest watching the films 'Contact' or 'The Minority Report', if you want to rough idea of how this machine would work, or research 'Project Looking Glass'.

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    58. 58. Phoenix85 07:36 PM 3/9/10

      Building a time machine is very easy and may have already been done. Inside the human brain is a tiny gland, called the pineal gland, which is a gate way for hyper dimensional travel (the ability to access time space). When the Pineal gland is reverse engineered into mechanical form (surprisingly easy), a time machine is created. I would suggest watching the films 'Contact' or 'The Minority Report', if you want to rough idea of how this machine would work, or research 'Project Looking Glass'.

      Reply | Report Abuse | Link to this
    59. 59. Phoenix85 07:36 PM 3/9/10

      Building a time machine is very easy and may have already been done. Inside the human brain is a tiny gland, called the pineal gland, which is a gate way for hyper dimensional travel (the ability to access time space). When the Pineal gland is reverse engineered into mechanical form (surprisingly easy), a time machine is created. I would suggest watching the films 'Contact' or 'The Minority Report', if you want to rough idea of how this machine would work, or research 'Project Looking Glass'.

      Reply | Report Abuse | Link to this
    60. 60. timetravel800 11:15 AM 4/18/10

      If I were to build a time machine (which is my goal), I would marry Albert Einstein (who is my favorite physicist of all time).

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    61. 61. timetravel800 in reply to smuthu2004 11:18 AM 4/18/10

      No, smuthu2004, you would not be ten years younger because the time traveler would not be affected by going through time. Only the world around him/her would be affected, the time traveler would not be part of the time stream during the split second it would take to travel back in time.

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    62. 62. jake01 09:01 AM 5/28/10

      Time viewing is the only possibility. Humans would not be able to withstand the multiple effects and survive. The Human race doesn't have the wisdom to even view other time periods because of the massive effects it could cause. Just knowing one micro second of the future could be sufficient to change it entirely for the worse. Micro changes could cause the birth of hundreds of Stalin's and forever alter the way this world would continue to exist. There are infinite branching possibilities that could occur and how could anyone know what is the best way to proceed. One person could change everything for everyone instantly. Unless every possible event is already happening anyway, could it be feasible to attempt to deliberately make intentional changes.

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    63. 63. sunny3552 03:19 AM 8/14/10

      this is a interesting topic about is it possible in our world that anyone can built this in future.why i ask this because now a days science is in upper level,thats what.

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    64. 64. sunny3552 03:20 AM 8/14/10

      this is a interesting topic about is it possible in our world that anyone can built this in future.why i ask this because now a days science is in upper level,thats what.

      Reply | Report Abuse | Link to this
    65. 65. sunny3552 03:23 AM 8/14/10

      this is a interesting topic about is it possible in our world that anyone can built this in future.why i ask this because now a days science is in upper level,thats what.

      Reply | Report Abuse | Link to this
    66. 66. jake01 01:07 PM 12/22/10

      We are all time travelers moving into the future every micro second. Imagine the horror if a democrat were to be able to use a time machine for their own agenda. It cannot be permitted, because no one on this Earth has the intelligence to do the right thing with such a power.

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    67. 67. Prasibaba in reply to astroguru 06:12 AM 9/10/11

      Great news. I would appreciate if you could please let us know more

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    68. 68. Prasibaba in reply to SeanDeneau 09:12 AM 9/10/11

      I would love to contact u, my email is psingh888@yahoo.com

      Reply | Report Abuse | Link to this
    69. 69. Prasibaba in reply to CorbinzRize 09:14 AM 9/10/11

      Good

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    70. 70. Prasibaba in reply to Phoenix85 09:30 AM 9/10/11

      I am surprised, can u explain me more about it

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    71. 71. XxsoulkillerxX 12:02 AM 11/15/11

      Wait if time machines can be built, if u stop something(EX 9-11-01 or stop someone from killing Kennedy) wouldnt the world change dramatically or if u change ur childhood?

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    72. 72. XxsoulkillerxX in reply to timetravel800 12:04 AM 11/15/11

      so ur saying if u want to change something u did like when you are in 10th grade and now your 26 years old you would be 24 years old at that time?

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    73. 73. thekingofzakariya 10:44 PM 4/11/12

      i am interested in its construction.please send me emails about it so i would be able to build such an amazing invwntion

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    74. 74. RickBeers 08:36 AM 6/9/12

      There is a pathway also explained at http://qesdunn.pbworks.com for being able to control time and space.

      It's based in string theory, but it also unifies gravity and instantaneous entanglement.

      If I could travel in time, I would go forward 10 year, where our current technology is still compatible. Use a flash drive and download every current development I could off the internet. Come back and give those developments to the original authors so they could carry forward more quickly in their developments.

      Then, do it again...

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    75. 75. RickBeers 09:01 AM 6/9/12

      XXXsoulkillerxX:

      According to QES we are able to clone our universe, causally move it forward or backwards, stop it at some point, change what we want, then let it move forward.

      So two universes would have two different timelines. Parallel universes.

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