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Thread: Time Travel Today

  1. #1 Time Travel Today 
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    There are many theories on time travel, and I was wondering, does anyone have any really practical ideas for a time machine. I mean blackholes and wormhole ideas aren't going to happen overnight or anytime soon are they? Which theory do you think would fit time travel easiest, personally I think relativity, but others may disagree and choose string theory or quantum mechanics. Is there anyway that we can create a time machine anytime soon, like today and not in the future?


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  3. #2  
    Administrator KALSTER's Avatar
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    I have no idea, but I expect you will get a reply from streamsystems as soon as she reads your post!


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  4. #3  
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    If you switch on a time machine, would reality be destroyed? Because if you physically move back or forth in time, you might cause everything to become one, making reality crash and destroy itself into oblivion. That is if time travel was possible. Is that a strange thought? Does that make sence at all?
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  5. #4  
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    well how about an observation trip back in time.
    like being able to see 2 years back into the past, by putting a mirror 1 lightyear away from earth.
    or how about bending spacetime, placing you 1 lightyear away from earth.
    you'd see earth as it was 1 year ago from your position.
    when you have eliminated the impossible, whatever remains, however improbable, must be the truth
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  6. #5  
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    Quote Originally Posted by dejawolf
    well how about an observation trip back in time.
    like being able to see 2 years back into the past, by putting a mirror 1 lightyear away from earth.
    or how about bending spacetime, placing you 1 lightyear away from earth.
    you'd see earth as it was 1 year ago from your position.
    That might get a little difficult though.
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  7. #6  
    Forum Freshman Kosta's Avatar
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    I was gonna post this in a new thread, but this will do. This guy has a theory for time travel. I just spotted it on cnn.com

    What do you all think about its practicality?

    http://www.cnn.com/video/#/video/tec...ime.travel.cnn
    In order to make an apple pie from scratch, you must first create the Universe. - Carl Sagan
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  8. #7  
    Forum Junior Twaaannnggg's Avatar
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    Who cares about time machines??
    I invented a space machine. But instead of entering the year you wanna visit you just punch in the ZIP-code. That'll teach 'em!!

    And btt......I can't tell you which theory might be the cornerstone of time travel but I know which is the tombstone: That goddam 2nd Law of Thermodynamics. Damn you, Entropy!!
    Build a man a fire and he will be warm for a day, set a man on fire and he will be warm for the rest of his life.
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  9. #8  
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    LOL!
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  10. #9  
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    Not that this is realistic, but I think your best bet for time travel would be to travel away from the earth at near-light speed, hang out for awhile, and come back. Little time has passed for you, but much has passed for the folks back on Earth, and when you come back, you'll be in the Earth's "future." As for travelling back in time, you'd have to travel at greater-than light speed, but that's a bit more out-there and I don't feel like thinking it through right now.
    "There is a kind of lazy pleasure in useless and out-of-the-way erudition." -Jorge Luis Borges
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  11. #10  
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    Although it is true that time and space are linked, it is however, that the speed of light must be the end result of the sum of the speed of space and time. As the physicist explained, the "string of time" is really what's called a light cone where the center is the present, the lower half is the past, and the upper half is the future. Any massive bodies would be allowed inside the future light cone as a projection from the present while these bodies cannot exist beyond the cone - meaning that their speed is confined to the speed of light. However, then on might ask what happens to those particles that are massless? What seems today is that they best they can do, (the most stable) is travel AT speed of light and RELATIVE to us, it's time seem stopped. However, sending partials such as Neutron back through time would really have to be broken down into Quarks; and neutrons are really just made out of two down Quarks, and one down Quark. These partials, given enough energy from space-time, (mostly kinetic) would then force them transform into anti-matter. However, the energy required to do this transformation is so great, that I don't think ANYONE on Earth can hope to do so. Which then therefore, really have no meaning to travel back in time - given that speed of light is the limit of all speeds.

    However, no scientific theory has ever proven the impossibility of time travel despite many attempts to put forth a contradictory argument for it. One of many is that the "Grandfather Paradox". Suppose one were to travel back in time and meets his father's father. Then we suppose that he killed him. Obviously then the question becomes: What would happen that guy who traveled in time? One reasonable answer is that the guy simply disappears. However, there is a mathematic model that's been developed to show that the probability of that guy killing his grand father is really zero, which then therefore, the time would be consistent with the one you travel back on. In this case it seems perfectly fine given enough math as support. However, one might then wonder the consequence of one going back in time and trying to save someone from death. According to our math model mentioned above, the person would find who ever he is trying to save would die in many different ways. Another word, no matter how hard he tries, he still fails to save the person from death. Specifically, one can change the course of time, but not the RESULT of time. It is like potential energy, which only cares for the initial position, and the final position. What is in between and what happened, is disregarded. From a glance, this makes perfect logical sense. That is because if one were to actually save that person, you wouldn't even be back in that time anymore! Therefore, that person have to KEEP dying IN ORDER to keep you going back in time; else the entire story wouldn't exist if you saved that person. This, interestingly, then lead one to question: What if I simply went back in time for no reason? And then it happens that by chance, I saved who ever I didn't mean to save? Now this is a bit of a problem. Usually this result is given that it is an alternative universe we've enter through time. Therefore, time in this case, really acted as space (remember that they are really the same time), which means we've really just traveled through a wormhole!

    Finally, all these are just suggestions made by humble scientists who look forth to new arguments and new theories. Therefore, your belief is yours.
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  12. #11  
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    I tend to think that there's simply a limit to time travel. If you look at time the same way as you look at space, then being in two different places at the same time is not very different from being in two different times at the same place.

    The second thing is very possible for us right now. You'd think that the first thing would be possible too, but how to do it? I don't know.

    I know one thing. Our mind is only programmed to be able to handle time going in one direction and at one apparent speed (from our perspective, anyway). I don't know how a person's sanity would hold up if that constant started to become more of a variable.
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  13. #12  
    Forum Freshman Tony John C's Avatar
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    Quote Originally Posted by Obviously
    If you switch on a time machine, would reality be destroyed? Because if you physically move back or forth in time, you might cause everything to become one, making reality crash and destroy itself into oblivion. That is if time travel was possible. Is that a strange thought? Does that make sence at all?

    Thats called the 5th dimension if i'm correct. Where all time becomes one thing.

    Edit: this is the link, its pretty interesting. http://www.tenthdimension.com/medialinks.php
    Why is hate so ingrained in humans? For the supposed enlightened species we are very limited to such primitive behaviors. Peace is a fleeting in our society.
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  14. #13  
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    Quote Originally Posted by Tony John C
    Quote Originally Posted by Obviously
    If you switch on a time machine, would reality be destroyed? Because if you physically move back or forth in time, you might cause everything to become one, making reality crash and destroy itself into oblivion. That is if time travel was possible. Is that a strange thought? Does that make sence at all?

    Thats called the 5th dimension if i'm correct. Where all time becomes one thing.

    Edit: this is the link, its pretty interesting. http://www.tenthdimension.com/medialinks.php
    Thanks, I'll sure check it out.
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  15. #14  
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    Very interesting video! Thank you for the enlightenment! It it, however, sounded like in the video that, fairly easy to "fold" higher dimension together and create a short cut. It is actually quite difficult! As you see that if we further analysis time line, we can deduct three major "Arrow of Time" (Steven W. Hawking). The first is the arrow of thermodynamic time. That is the arrow of entropy. Another word, things always tend to increase in entropy but not decrease. Imagine that a cup is now broken from the motion which it dropped or fall from a table. This would increase the entropy of the cup because it'd be in a higher disordered state. However, if we were to imagine that the arrow part of this time line is pointing in the opposite direction, we'd then see the cup getting up and assemble into the original cup from all its broken pieces! This is never seen in our daily lives! Given that our universe has the tendency of following the arrow of thermodynamic towards increase in entropy, it is relatively safe to suggest that the arrow will always point in that direction. The second arrow of time would be discribed as the psychological arrow of time. The reason we always advance from an infant to adult and then elders and finally death is because our arrow of time always points forward. Imagining we were to reverse this direction. We'd then be remembering things from the future! and not the past! Of course, we'd then some how rise from death and slowly grow backwards and become an infant and finally into embryo and finally disappear (or simply becomes parts of DNA condons). However, if the world would truly be like this, it'd violate the increase of entropy! Since when ever we move, we spent energy which would increase the entropy of our surroundings and therefore have done work. However, if this were to be reversed, we'd then decrease our surroundings' entropy and have things such as heat that land on us and magically make themselves into ordered forms and give us energy while we reverse our motion! Therefore, given the first arrow of time, our psychological arrow of time would also go in the direction of the first arrow. Lastly, the final arrow of time is the arrow which points in the direction such that our universe is expanding and not contracting. Theories have suggested that different rules would be applied to contracting universes than expanding universes. Simply we've observed that our universe is expanding and not contracting, we can relatively safe to say that it is pointing that way and it will not change direction for a long time.

    Therefore, given these description of time, it would be extremely difficult work to "bend" time and force it to change in direction. Many problems would arise such as "Grandfather Paradox" I mentioned before.

    However, as we work out the math in General Relativity, we are some what "forced" to treat time into something called "Imaginary Time" like we'd treat square root of negative numbers into imaginary numbers. In this sense, time does not have any difference compared to space. Therefore, it is still an open argument about going back in time - simply bend space around us.
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