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Movie: K-PAX, makes sence?

  1. Apr 14, 2003 #1
    I have recently seen the movie K-PAX starring Kevin Spacey. In it he is supposedly from the planet K-PAX and goes onto explain how it is a few thousand lightyears away.

    The doctor questioning him wants to know how he got here and he said he harnessed his energy onto a beam of light or something to this effect. He then said that they would travel and many times the speed of light and when told that Einstein said that nothing can exceed to the speed of light he told the doctor he was wrong.

    That what Einstein really said is that nothing could exceed up to the speed of light because its mass would become infinite but that Einstein said nothing about entities already travelling at or above the speed of light.

    Anyway, does this hold any water? What do you think about this? And to anybody who has seen the movie also, can you point out some interesting physics about the movie?
  2. jcsd
  3. Apr 14, 2003 #2

    the movie is correct. einstein never said that nothing can travel faster than the speed of light.

    he does say that something that is traveling slower than light is slower than light in all reference frames, and cannot accelerate to a speed above the speed of light.

    since kevin spacey is standing in that office at rest, it seems that he would have to have accelerated from below the speed of light, to above the speed of light, and that is not possible.

    however, they didn t go into many details about what mechanisms he used, it was very vague, so it is hard to comment.

    however, at the end oof the movie, you are left with the impression that the physical human body that he is inhabiting is not him, so perhaps they are implying that some "essence" of his person travelled faster than light, and then inhabited the massive human body when it arrived on earth. sketchy though.
  4. Apr 14, 2003 #3
    I am wondering then, how fast is it possible to go? Do we know of anything that is currently zipping through the universe at multiple speeds of light?
  5. Apr 14, 2003 #4
    Theoretical entities termed 'tachyons' have the potential to travel at any multiple of c greater than 1. They remain inviolate of the laws of special relativity due to their imaginary rest mass; that is, a mass modified by the imaginary unit i = sqrt(-1). Although there does seem to be preliminary evidence for their existence as a type of quasi-particle within laser-like mediums.
  6. Apr 17, 2003 #5


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    It is my understanding that there may indeed be particles that travel faster than the speed of light "tachyons" and that they can travel at any multiple of c. However it is also my understanding that as we exist in the universe as <=c we cannot detect anything that is >c. We will therefore never know if Tachyons exist as we will never be able to detect them.

    However it was a good film.
  7. Apr 17, 2003 #6
    Oh, I thought that movie was scary (at least the part when the K-pax dude is recalling the death of his wife or something).

    Anyway, Joao [something] has been working on a Varying Speed of Light theory since 1997. His theory is excellent. It permits superluminal travel to occur, theoretically. this is a good article:
    http://education.guardian.co.uk/Print/0,3858,4617019,00.html [Broken]
    Last edited by a moderator: May 1, 2017
  8. Apr 18, 2003 #7
    The only problem with 'tachyons' is that they usually wind up having negative or imaginary probability waves associated with them, which does not make any physical sense, hence why most theorists working on various TOE's tend to dismiss any theory that includes them.
  9. Apr 18, 2003 #8
    No, Ploegman. I don't think that that part of K-Pax made any sense. Here is why. He said that, even after harnessing the movement of something that was going faster than the speed of light, it took him a long time to get here. Special Relativity shows that, if something were to go faster than c, time would be backward for that object. "Prot" would have had to have arrived on Earth before he departed K-PAX, because time would be backward.
  10. Apr 18, 2003 #9
    I just read the article. While I applaud this Scientist's "pushing the envelope" there are many things that are either obviously wrong, or obviously misrepresented in the article.

    For example:
    Prof. Magueijo appears to be postulating that reality came from a "Sea of Nothingness". As I've already shown repeatedly, on the Philosophy Forum, "nothingness" has no meaning, because that implies the "essence of that which isn't something". There cannot be something that isn't something.

    Prof. Magueijo also appears to be postulating something that people have known for a very long time, and that Einstein himself allowed for. He appears to just be saying that the speed of light isn't constant under extreme heat or extreme gravitational pull. Einstein's General Relativity already covers this. All that Einstein was saying was that the speed of light in vacuo is constant.

    Anyway, someone should probably start a thread about this, so that I don't side-track this one (I hope I haven't already).
    Last edited by a moderator: May 1, 2017
  11. May 21, 2003 #10


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    Right, that was my first impression when hearing that...BUT...it still takes him 7 years or whatever he said to travel..I mean if ure traveling back in time, you dont do it infinitely fast right? Im saying that it took him a certain amount of time(7 years i think he said) to travel whatever amount of time backwards...wierd..yeah..

    I have to write a paper that brings together evidence that he really is an alien and not a nutcase..I guess Ill be doing it more in the sense of his knowledge rather than the physical possibility that he is travelled faster than the speed of light
  12. May 22, 2003 #11
    Well, for one, traveling infinitely fast is impossible, theoretically.
    Prot traveled at the speed of light from K-pax. How long did it take him? no time at all. Time doesn't effect things that travel faster than light, therefore, it really didn't take him any time. Ah, another paradox of movies!
  13. May 22, 2003 #12


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    ok I know THAT it wouldnt take any time if he were traveling the speed of light. However he even said it himself, that its impossible to accelerate to the speed of light, and that its impossible to travel at the speed of light.

    What he said is that its possible for something to travel faster than the speed of light if it never has to accelerate to and past c.

    So what I'm saying is that it would still take him time to get to earth, but it would be negative time.

    On another note, does time dialation occur at speeds >c?
  14. May 22, 2003 #13
    Backwards??? I've never heard this, how could time reverse, I always thought it stayed the same, he would age normally, while it slowed down all around him and everybody else would age much faster.
  15. May 22, 2003 #14
    No, you missed my point slightly, I think. Relativity dictates that anything going at a speed faster than that of light will travel backward in time. This is not some simple phenomenon to discuss, as it implies arriving at Earth before ever leaving K-Pax. Think about it.
  16. May 22, 2003 #15
    It's a simple postulate of Relativity. If one reaches the speed of light (which one cannot do, but if they did) one stands absolutely still in time. If they exceed the speed of light (which they also cannot do...) they move backward in time.

    An analogy, to help explain:

    Let's say you are driving a racecar from one end of a field to the other. Let's say that you can travel at exactly constant velocity for the entire ride. Let's also say that it takes you exactly 1 minute to make it their, when you travel at constant velocity (meaning that your speed and direction remain exactly the same). Now, try traveling to the end, but at a slight angle. It would, logically, take you longer to do so, because your speed is distributed over more than one dimension now (instead of just being straight, you now have to go forward, and a little side-ways).

    Now, according to Relativity, our movement is always exactly equal to "c" (the speed of light). However, it is distributed between spacial movements and your movement through time. Meaning that if you speed up in space, you slow down in time (just as when I give more of my speed to going "left" I have less for going "forward").

    Does this make more sense?
  17. May 22, 2003 #16

    Yes, he said that, but he was wrong. He would be right to say that there are things already traveling at c, but not beyond it.

    Listen to yourself. You are saying it would take him "negative time"! That's like saying there is a negative amount of space between you and me. (Please see my response to your previous post).

    (See response to kyle_soule).
  18. May 22, 2003 #17

    Worse, actually, he said that he traveled many times faster than light!

  19. May 22, 2003 #18
    i have a question that runs on a similar line. i don't think that the movie has any good points but how about this: if e=mc2 then the mass of our bodies, a ship, ect. could theoritically be converted into a higher form of energy-such as light- and there for travel at the speed of light. somehow (i know-a very vauge word) one could also reverse the process and returt from a state of energy to a state of matter-again SOMEHOW collected back into your human form. if the matter of our bodies IS energy, couldn't this be theoretically possible.
    of course i reilize that even if one could travel at the speed of light be removing, or converting any mass into energy, it would still take hundreds of years to travel to any star of other planet but hey this is the theortical forum.
    ohhh, also... if one reads einsteins works, one gets the empression that he said that if an object accelerated to the speed of light one would in a sence slow time down through a process i'm not going to type out, but anyways: wouldn't this mean that to a photon of light, its travel is instantanious from one point to another...
    sorry i threw a lot out...
  20. May 22, 2003 #19
    All of this would be possible, but, in the process of transforming all of your matter into pure energy, you "die", obviously. You cannot live, if there are no material/chemical reactions happening.

    Besides, it'd still take a really long time!

    Well, yes, if you were looking from the photon's point of view, your travel would "feel" instantaneous, but I don't think the photon really thinks about this kind of thing anyway :wink:.
  21. May 22, 2003 #20
    Yes, very much, thank you. You didn't have to spell it out quite so much

    My mistake came due to the idea that you cannot travel faster than C, which is correct, but I forgot we were assuming you could for the movie's sake.
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