K-PAX: A Scientific Analysis of Interstellar Travel and the Speed of Light

  • Thread starter Ploegman
  • Start date
  • Tags
    Movie
In summary, the movie K-PAX portrays the idea that faster-than-light travel is possible and that it is not limited by Einstein's theory of relativity. However, the concept of tachyons, particles that can travel faster than light, is still theoretical and not yet proven. Some scientists are working on theories that could potentially allow for superluminal travel, but these theories are still in the early stages and have not been widely accepted in the scientific community. While the movie is entertaining, it should not be taken as a factual representation of physics.
  • #1
Ploegman
14
0
I have recently seen the movie K-PAX staring 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 traveling 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?
 
Physics news on Phys.org
  • #2
Originally posted by Ploegman
I have recently seen the movie K-PAX staring 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 traveling 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?


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 traveled faster than light, and then inhabited the massive human body when it arrived on earth. sketchy though.
 
  • #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?
 
  • #4
Originally posted by Ploegman
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?

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.
 
  • #5
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.
 
  • #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:
  • #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.
 
  • #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.
 
  • #9
Originally posted by MajinVegeta
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]

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:
  • #10
Originally posted by Mentat
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.
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 don't do it infinitely fast right? I am 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 traveled faster than the speed of light
 
  • #11
Originally posted by dav2008
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 don't do it infinitely fast right? I am 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..

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!
 
  • #12
Originally posted by MajinVegeta
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!
ok I know THAT it wouldn't 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 dilation occur at speeds >c?
 
  • #13
Originally posted by Mentat
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.

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.
 
  • #14
Originally posted by dav2008
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 don't do it infinitely fast right? I am 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 traveled faster than the speed of light

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.
 
  • #15
Originally posted by kyle_soule
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.

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 spatial 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?
 
  • #16
Originally posted by dav2008
ok I know THAT it wouldn't 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.


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.

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

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).

On another note, does time dilation occur at speeds >c?

(See response to kyle_soule).
 
  • #17
Originally posted by MajinVegeta
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!

Exactly.

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

LOL
 
  • #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 sense 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...
 
  • #19
Originally posted by maximus
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.

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!

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 sense 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...

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:.
 
  • #20
Originally posted by Mentat
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 spatial 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?

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.
 
  • #21
Originally posted by kyle_soule
Yes, very much, thank you. You didn't have to spell it out quite so much

Yeah, I didn't assume I had to, if I were just explaining it to you, but others will read it, so I wanted to make sure it was perfectly understandable.

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.

An honest mistake. When I first watched the movie, it was before I posted against the existence of tachyons (in one of MajinVegeta's old threads), and so I wasn't positive about whether Prot was right or not.
 
  • #22
just to clear up

i don't know anything about light speed but here's what i wanted to add to this post...

the body that "prot" was in wasnt an alien. it was a disabbled man.The movie was suggesting that Prot traveled on beams of light and when he got to Earth he had to inhabit something that was already living on earth. so he landed in the disabbled mans body.he didnt have complete mental control over it though.he was basicaly sharing the body with the disabbled man mentaly but not physicly. that's why he had the thoughts of his wife drowning and those other weird thoughts that would suggest he wasnt an alien. those thoughts belonged to the disabled man. At the end of the movie prot left Earth on a beam of light(some how). when he left he left the body of that guy as he was originaly...disabled
 
  • #23


Originally posted by monkeysk8er
i don't know anything about light speed but here's what i wanted to add to this post...

the body that "prot" was in wasnt an alien. it was a disabbled man.The movie was suggesting that Prot traveled on beams of light and when he got to Earth he had to inhabit something that was already living on earth. so he landed in the disabbled mans body.he didnt have complete mental control over it though.he was basicaly sharing the body with the disabbled man mentaly but not physicly. that's why he had the thoughts of his wife drowning and those other weird thoughts that would suggest he wasnt an alien. those thoughts belonged to the disabled man. At the end of the movie prot left Earth on a beam of light(some how). when he left he left the body of that guy as he was originaly...disabled

the dude prot inhabited was schizophernic, right?

Anyway, you can't travel on light beams, can you?
 
  • #24
well the movie was implying prot could travel on light beams. but obviously we don't know how to.
 
  • #25
i guess what prot/e was saying when he said you could go the speed of light as long as you don't have to accelerate that fast was that...you could travel on something like light because you would never have to accelerate that fast.your going that fast as soon as you would get on it. its like...lets say it was impossible to reach 50mph unless you didnt have to accelerate. you could jump on a bus that is moving 50mph but you couldn't get on the bus at o mph and then accelerate to 50mph
 
  • #26
Originally posted by monkeysk8er
i guess what prot/e was saying when he said you could go the speed of light as long as you don't have to accelerate that fast was that...you could travel on something like light because you would never have to accelerate that fast.your going that fast as soon as you would get on it. its like...lets say it was impossible to reach 50mph unless you didnt have to accelerate. you could jump on a bus that is moving 50mph but you couldn't get on the bus at o mph and then accelerate to 50mph

There is a large difference though, in that, when one reaches the speed of light, time begins to run backward. This is not true of traveling 50 m.p.h.
 
  • #27
Mentat, I thought that when you're traveling at c, time doesn't flow at all. Of course, I think this doesn't quite make sense...
 
  • #28
Originally posted by MajinVegeta
Mentat, I thought that when you're traveling at c, time doesn't flow at all. Of course, I think this doesn't quite make sense...

Yes, as I pointed out in my analogy, we are always traveling at c. But if we use all of that speed on spatial movement, we have none left for time, and we thus do not move in time at all.
 
  • #29
Hi. Just a quick rundown of what i think

Since prot said that nothing can accelerate to the speed of light or more than the speed of light;and whatever tachyons are,they have to first start traveling at some speed before reaching speeds of many multiples of c,so,how is it that tachyons can exist in the first place since they must initially startout from some small speed way below c?

I'd like to know the answer. Can someone enlighten me on this please?i'd appreciate that.

It's self-contradicting what prot had said.
 
  • #30
Sorry about raising the dead but I was searching for k-pax quotes and came across this so i registered.

Tachyons began their existence traveling at a multiple of c so they don't have to accelerate. Also to all you thinking time is linear, I don't believe its possible to go backwards in time at all. You can distort space/time (for eg time delation) but I believe that time can't go backwards. it comes to a point when time relatively stops (or passes infinitly slow) but doesn't really ever stop or reverse otherwise it would seem that the thing in question would not exist. .02. If anyone even reads this anymore post some more interesting things. I like to read them. thanks
 
  • #31
Mentat said:
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 spatial 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").

people, people, people.

Calculate the time required to travel using Mentat's racecar example (above) and the Phythagorean Theorem and you shall get that the time is not "negative time" but it is an imaginary number:

c = speed of light, n = speed of Prot (n > c), t = time

c^2 = n^2 + t^2

t^2 = c^2 - n^2
c^2 < n^2
t^2 < 0

you get that t^2 is a negative number.
t is an imaginary number
 
Last edited:
  • #32
Say, a movie I've actually seen!

Forget the math, was the man insane or not is all I care to know.
 
  • #33
mentat, please, tell me where you got that racecar example, please, I need to know.

boulderhead, i would say that he was not insane. seeing that he can detect UV rays, communicate with animals, and he explains how he got here really good. and unless anywhere in the movie it says that the disabled man knows einstein's special theory of relativity really well, i would say that he is not crazy.

NOT CRAZY
 
Last edited:
  • #34


no but u 2 are.

lol
 
  • #35
if it takes an infinite amount of energy to accelerate to the speed of light does it take something traveling above c an infinite amount of energy to slow down to the speed of light
 
<h2>1. What is the premise of "K-PAX" and how does it relate to interstellar travel?</h2><p>The premise of "K-PAX" is that a man named Prot claims to be an extraterrestrial from the planet K-PAX, which is located in a distant galaxy. He also claims to have traveled to Earth using advanced interstellar travel technology. This relates to interstellar travel because it raises questions about the feasibility and limitations of such travel.</p><h2>2. How does the concept of "K-PAX" challenge our current understanding of the speed of light?</h2><p>In the movie, Prot claims to have traveled faster than the speed of light to reach Earth. This challenges our current understanding of the speed of light, which is believed to be the maximum speed at which anything can travel in the universe. It raises questions about the possibility of breaking this speed limit and the potential consequences of doing so.</p><h2>3. Is there any scientific evidence to support the existence of a planet like K-PAX?</h2><p>As of now, there is no scientific evidence to support the existence of a planet like K-PAX. However, with the advancement of technology and space exploration, there is always a possibility of discovering new planets and civilizations in the future.</p><h2>4. Can the technology used for interstellar travel in "K-PAX" be achieved in real life?</h2><p>Currently, the technology used for interstellar travel in "K-PAX" is purely fictional and not achievable in real life. However, scientists are continuously researching and developing new technologies that could potentially make interstellar travel a reality in the future.</p><h2>5. What are some challenges and limitations of interstellar travel, as portrayed in "K-PAX"?</h2><p>In "K-PAX", Prot mentions the challenges of navigating through space and avoiding collisions with objects. He also mentions the physical and psychological toll of traveling at high speeds. Additionally, the concept of time dilation, where time passes differently for travelers and those on Earth, is also portrayed as a limitation of interstellar travel.</p>

1. What is the premise of "K-PAX" and how does it relate to interstellar travel?

The premise of "K-PAX" is that a man named Prot claims to be an extraterrestrial from the planet K-PAX, which is located in a distant galaxy. He also claims to have traveled to Earth using advanced interstellar travel technology. This relates to interstellar travel because it raises questions about the feasibility and limitations of such travel.

2. How does the concept of "K-PAX" challenge our current understanding of the speed of light?

In the movie, Prot claims to have traveled faster than the speed of light to reach Earth. This challenges our current understanding of the speed of light, which is believed to be the maximum speed at which anything can travel in the universe. It raises questions about the possibility of breaking this speed limit and the potential consequences of doing so.

3. Is there any scientific evidence to support the existence of a planet like K-PAX?

As of now, there is no scientific evidence to support the existence of a planet like K-PAX. However, with the advancement of technology and space exploration, there is always a possibility of discovering new planets and civilizations in the future.

4. Can the technology used for interstellar travel in "K-PAX" be achieved in real life?

Currently, the technology used for interstellar travel in "K-PAX" is purely fictional and not achievable in real life. However, scientists are continuously researching and developing new technologies that could potentially make interstellar travel a reality in the future.

5. What are some challenges and limitations of interstellar travel, as portrayed in "K-PAX"?

In "K-PAX", Prot mentions the challenges of navigating through space and avoiding collisions with objects. He also mentions the physical and psychological toll of traveling at high speeds. Additionally, the concept of time dilation, where time passes differently for travelers and those on Earth, is also portrayed as a limitation of interstellar travel.

Similar threads

  • Other Physics Topics
Replies
9
Views
1K
  • Special and General Relativity
2
Replies
45
Views
3K
  • Aerospace Engineering
Replies
5
Views
1K
  • Special and General Relativity
Replies
8
Views
1K
  • Special and General Relativity
Replies
3
Views
1K
  • Special and General Relativity
Replies
27
Views
3K
  • Special and General Relativity
Replies
13
Views
1K
  • Special and General Relativity
Replies
28
Views
4K
Replies
7
Views
1K
Replies
8
Views
2K
Back
Top