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Time travel

  1. Nov 18, 2003 #1
    hello all!

    here is my question.
    Is it theoretically possible to time travel to the earth's future and it's past???

  2. jcsd
  3. Nov 18, 2003 #2


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    As far as present-day understanding goes, no.

    And the earth's past is far away behind us in space. The whole solar system is travelling through space at hundreds of miles per second. To go back to yesterday you'd need a spaceship.
  4. Dec 5, 2003 #3
    To follow some error events. travel in time was right past time

    to travel in time. that is happen as some past event perhaps , but the secret and rule is not clearn now. to move a particle is complex very in time dimension. so to move earth it is very hard now. very hard.
  5. Dec 6, 2003 #4
    Time Travel ? No Way

    Time Travel? is a popular theme in Sci-Fi movies and books
    but unless you are a comic book character, I think it will never happen. Dr.
    Kaku thinks the same thing I believe. I listen to the late night talk show on
    AM radio :Coast to Coast AM and am constantly amazed at the stupid people
    who call in to George Noory with their goofy stories about paranormal sightings
    and their observations of "Mysterious events" which are probably made up
    stories or mistaken observations of common events. The latest thing reported
    by the Monday thru Friday talk host :George Noory is that he will try and take a
    TIME TRAVEL trip via a "Inventor he has contacted. Many people send him Email
    and call him to advise him NOT to do this as if this is entirely POSSIBLE ! George
    who seems to have only movie adventures as any scientific experience and
    shows his lack of any real paranormal background by the questions he asks his
    radio guests is replaced by ART BELL on the weekends who does have a fair
    amout of smarts in this field.

    I admit that I have only my opinions and no experience to say the above and
    feel that Time Travel will remain only in Science fiction stories but then they said
    that we would never travel to the Moon or if you traveled faster than 30 miles an
    hour in a motorcar you would die because you could not breathe with the air
    moving so fast past you.....so perhaps I am wrong about Time Travel.

    Another topic : The Star trek matter Transmitter???? Now is that possible???
  6. Dec 6, 2003 #5
    The problem is that you can't say, 'Hey, what would happen if you could go faster than the speed of light?' because that's totally physically impossible. It's not possible to go faster than the speed of light, so the laws of physics can't possibly say what would happen if you imagine things that way in some hypothetical universe. Physics is a complete package: once you decide to ignore one physical law, you're ignoring them all.

    You run into a similar problem when you ask 'What if I could divide by zero?' or 'What if I could build a perpetual motion machine?' or 'What if I went back in time and killed my grandfather before I was born?' There's no answer, because the question doesn't make any sense.

    Of course, this doesn't bother the writers of Star Trek. They go faster than the speed of light every show and travel into the past like it's a trip to Disneyland. This brings up an interesting point, however: The idea of a space-warping engine is NOT entirely a bad one! Warping space would allow you to travel as if you were moving faster than light by changing the structure of the universe, at least temporarily. You would end up in a certain location much faster than if you travelled there the 'normal way,' kind of like a secret passage. Happily for relativity, you would STILL not actually be travelling faster than the speed of light in local space, so Einstein's 'speed limit' still holds.

    The point is that though it's fun to think about and enjoy in science fiction, truly going faster than the speed of light is a violation of the laws of physics and therefore can not really be discussed by physics. I can't say time would reverse itself or not exist or anything because those aren't even options. It's like if I invited you out to dinner and you told me you absolutely couldn't come, but then I asked you whether you were going to have the soup or the salad!

    Today, we know that time travel need not be confined to myths, science fiction, Hollywood movies, or even speculation by theoretical physicists. Time travel is possible. For example, an object traveling at high speeds ages more slowly than a stationary object. This means that if you were to travel into outer space and return, moving close to light speed, you could travel thousands of years into the Earth's future.

    Angelus Silesius, a sixth-century philosopher and poet, thought the flow of time could be suspended by mental powers:

    Time is of your own making;
    its clock ticks in your head.
    The moment you stop thought
    time too stops dead.

    If you can imagine, I think you can accomplish. That's my motto.
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