Faster than the speed of light...

[mreddie1611]

I have a different way of looking at Einstein than most, that makes faster than light travel possible, without bending any rules. At least, I think I do. Special Relativity says that space-time dilates at near light speed velocities, and that the time slows down for the traveler. As the old story goes, 100 years pass on earth, while only a few years pass for the traveler on the near light speed ship. This is not merely a matter of perception on the part of the either the traveler or the earthbound observer. This is the reality of the space that both parties inhabit. Relativity says that time doesn't just seem to slow down for the traveler, time actually does move slower.

 

As a thought experiment, lets have our traveler make a 100 light year journey from earth to a distant star in our galaxy, at speeds very close to the speed of light. Space-time shortens, or dilates, but only for the traveler, not for us earthbound observers. From our point of view the traveler's journey takes over 100 years to complete. From his point of view, though, only 50 years have passed, and when he comes to his journey's end, he has traveled over 100 light years in 50 years of his time... or, to put it another way, he has traveled, from his point of view, at NEARLY TWICE THE SPEED OF LIGHT.

 

Our thought experiment is not an extreme one. Near light speeds might result in only 10 years passing for the traveler on a 100 light year journey. The scale if infinite, with time coming to a complete stop if actual light speed were possible to obtain. Our traveler looked out the window of his ship and saw the asteroid that marked the halfway point of his trip pass by in just a little over 25 years. The only real question, in my mind, is whether this is a matter of perception on the part of the traveler, or if it is a matter of reality. For those of us on earth to insist that the trip actually took over 100 years is to insist that our reality is correct, and that his is false. Or, to put it another way, he was being effected by Special Relativity, whereas we were... not? Doesn't Special Relativity effect any object that moves through space, even those of us at our computers right now, though at an infinitesimal scale until near light speeds are attained? Can you really say that time is passing for you right now in the exact same way as it is for me?

 

Why is our perception "real" and the traveler's only an illusion? Time, space, and velocity are all relative, aren't they? Is the near light speed traveler actually exceeding the speed of light, at the cost of the dimension of time?

Edited February 5, 2011 by mreddie1611

[Janus]

I have a different way of looking at Einstein than most, that makes faster than light travel possible, without bending any rules. At least, I think I do. Special Relativity says that space-time dilates at near light speed velocities, and that the time slows down for the traveler. As the old story goes, 100 years pass on earth, while only a few years pass for the traveler on the near light speed ship. This is not merely a matter of perception on the part of the either the traveler or the earthbound observer. This is the reality of the space that both parties inhabit. Relativity says that time doesn't just seem to slow down for the traveler, time actually does move slower.

 

As a thought experiment, lets have our traveler make a 100 light year journey from earth to a distant star in our galaxy, at speeds very close to the speed of light. Space-time shortens, or dilates, but only for the traveler, not for us earthbound observers. From our point of view the traveler's journey takes over 100 years to complete. From his point of view, though, only 50 years have passed, and when he comes to his journey's end, he has traveled over 100 light years in 50 years of his time... or, to put it another way, he has traveled, from his point of view, at NEARLY TWICE THE SPEED OF LIGHT.

No, because by his measurement, the distance has contracted to 50 ly.(this not exactly right because the time dilation ratio in this example is not correct. For example, at 99% of c the factor would be 7.)

 

Our thought experiment is not an extreme one. Near light speeds might result in only 10 years passing for the traveler on a 100 light year journey. The scale if infinite, with time coming to a complete stop if actual light speed were possible to obtain. Our traveler looked out the window of his ship and saw the asteroid that marked the halfway point of his trip pass by in just a little over 25 years. The only real question, in my mind, is whether this is a matter of perception on the part of the traveler, or if it is a matter of reality. For those of us on earth to insist that the trip actually took over 100 years is to insist that our reality is correct, and that his is false. Or, to put it another way, he was being effected by Special Relativity, whereas we were... not? Doesn't Special Relativity effect any object that moves through space, even those of us at our computers right now, though at an infinitesimal scale until near light speeds are attained? Can you really say that time is passing for you right now in the exact same way as it is for me?

 

Why is our perception "real" and the traveler's only an illusion? Time, space, and velocity are all relative, aren't they? Is the near light speed traveler actually exceeding the speed of light, at the cost of the dimension of time?

Space and time are relative. Because of this there is no "who's perception is 'real'". If you and are are passing it other at 87% of the speed of light we each will see the other's clock as running half as slow as ours, and see each others length contracted in half, and each of our perceptions is equally 'real'.

 

With the example of the space traveler, the only way to compare who aged less is to bring them back together, and to do this the space traveler has to turn around and return to Earth, and this turn around is what decides who's clock accumulated less time during the trip.(basically due to something called the "Relativity of Simultaneity")

[lemur]

As a thought experiment, lets have our traveler make a 100 light year journey from earth to a distant star in our galaxy, at speeds very close to the speed of light. Space-time shortens, or dilates, but only for the traveler, not for us earthbound observers. From our point of view the traveler's journey takes over 100 years to complete. From his point of view, though, only 50 years have passed, and when he comes to his journey's end, he has traveled over 100 light years in 50 years of his time... or, to put it another way, he has traveled, from his point of view, at NEARLY TWICE THE SPEED OF LIGHT.

I doubt your numbers are correct, but I can't do the math either so I'll just go by the numbers you gave anyway. The interesting part of your story, imo, is that the 100 light years are experienced as taking only 50 years to the traveller. So if the 100 light years for Earth's perspective is a true distance, then how could it only take 50 years for the traveller if nothing can exceed the speed of light?

 

Also, it's a good point about assuming that Earth is not already traveling close to the speed of light relative to some slower moving entity. There may be some distant planet where a month on Earth takes a year. Humans living their could live out their lives from childhood to old age in 6 Earth years!

 

Doesn't Special Relativity effect any object that moves through space, even those of us at our computers right now, though at an infinitesimal scale until near light speeds are attained? Can you really say that time is passing for you right now in the exact same way as it is for me?

Just think that intellectuals just a few decades ago would have to have discussions like this via post where each letter could take days or weeks to arrive and the response just as long. Compared to them, we have years worth of discussions every week.

Edited February 6, 2011 by lemur

[phyti]

The only real question, in my mind, is whether this is a matter of perception on the part of the traveler, or if it is a matter of reality.

It's altered perception. All processes that involve light

propagation occur at a slower rate for moving objects, because light

has one speed in space. This would include the mind. If you give

someone a hallucinogen, the images in their mind are real, yet those

who do not participate do not share the experience.

For those of us on earth to insist that the trip actually took over 100 years is to insist that our reality is correct, and that his is false.

His is not false, just different.

Can you really say that time is passing for you right now in the exact same way as it is for me?

Time doesn't pass. Events happen at different rates depending on

your motion through space. I can set my clock to run fast or slow

for a week, yet the number of sunsets remains the same, i.e., my

clock is not relevant to events in the world, it's only a convenient

tool to count and order those events.

Why is our perception "real" and the traveler's only an illusion?

If everyone is moving, then all perception is 'real' or 'illusion'.

The choice is whatever makes you feel secure.

[swansont]

It's altered perception. All processes that involve light

propagation occur at a slower rate for moving objects, because light

has one speed in space. This would include the mind. If you give

someone a hallucinogen, the images in their mind are real, yet those

who do not participate do not share the experience.

 

"Altered perception" is a term that can be easily misinterpreted. Relativity isn't a trick of the mind, like an optical illusion is. All inertial frames are equally valid, and what you measure in your frame is reality.

 

You can get people to agree to use a particular frame for convenience, but that's politics, not physics.

[phyti]

"Altered perception" is a term that can be easily misinterpreted. Relativity isn't a trick of the mind, like an optical illusion is. All inertial frames are equally valid, and what you measure in your frame is reality.

 

You can get people to agree to use a particular frame for convenience, but that's politics, not physics.

 

I prefer 'altered perception' over 'magic' anytime.

There should be no misinterpretation. In the hallucinogenic case there is nothing in the outside world corresponding to the mental images. In the a-naut case there is.

 

No, it's not a trick, just physics. The a-nauts' perception of time and space are real to him. Why doesn't the moving a-naut not question his slower rate clock, because his slower rate mind can't detect any difference, thus you have 'proper time'.

I raise this point because some people think only the clocks run slower.

 

What else is there besides images in the mind? That's all you have through sensory input from the 'outside' world.

 

As for optical illusions, are things 'really solid', is the moon 'really a sphere'? We use abstract images/concepts/notions to model the physical world.

So it seems the illusion is in our mind and the corresponding reality is external.

[md65536]

Personally, one of the biggest challenges I've had with relativity involves keeping all the different frames of reference straight.

 

 

As a thought experiment, lets have our traveler make a 100 light year journey from earth to a distant star in our galaxy, at speeds very close to the speed of light. Space-time shortens, or dilates, but only for the traveler, not for us earthbound observers. From our point of view the traveler's journey takes over 100 years to complete. From his point of view, though, only 50 years have passed, and when he comes to his journey's end, he has traveled over 100 light years in 50 years of his time... or, to put it another way, he has traveled, from his point of view, at NEARLY TWICE THE SPEED OF LIGHT.

You're using time from one frame (50 years have passed according to the moving traveler's clocks) and distance from another frame of reference (rest distance from basically anyone's point of view while at rest).

 

Think of it this way: You can either determine the traveler's velocity using a rest frame, or using the traveler's moving frame.

In the former, just over 100 years have passed, and 100 light years have been traveled, and v is near c.

In the traveler's frame, 50 years have passed, but he has only traveled just under 50 light years (due to length contraction), and v is the same value: near c.

 

The key mistake to avoid is this: If I'm traveling relative to other locations, the time at those locations relative to me will be passing at different rates relative to my own time (that is, clocks on my rocket ship can appear to pass "normally"). If you're measuring change in relative distance, you must use relative time (not traveler's local time) to measure speed.

 

 

 

Yes, if I can move at near-c speeds, I can cover great rest distances in what appears to be a short amount of time to me, but relative to anywhere I travel, great amounts of time must also pass.

[mreddie1611]

I appreciate everyones input, and I can't say that I disagree with the generally accepted interpretation of Special Relativity. It took me several months just to wrap my head around how Einstein came to his conclusions and what they mean (it really kind of grabs you and doesn't let go, doesn't it?), so I don't really feel qualified to disagree. I just have this itch in the back of my mind that says that there may be room somewhere for a different idea. If you'll indulge me just once more, I'd like to go just a little further and get some feedback on what's really bugging me. I'm not changing the question, I'm just following the idea, right or wrong, to a conclusion...

 

It's impossible for our traveler to attain the speed of light, of course, but lets say for sake of argument that he could. Relativity says that that time for the traveler would come to a complete stop and that space for the traveler would be an infinitely flat plain, because the space-time dilation would be what I'll just call Zero, for lack of a better term. (come to think of it, there probably is a better term out there somewhere)

 

An infinite amount of energy is required to attain and maintain this speed. Not just big, incredible, unknowable amount of energy, an infinite amount of energy. I assume that this conclusion is due to my old nemesis, the math, which I don't understand but can accept that others have correctly worked out.

 

The traveler begins his 100 light year journey now at light speed, and maintains it throughout the journey until he reaches his destination. Einstein says, to best of my understanding, that our traveler experiences his journey as an instantaneous event. Furthermore, he does not really experience it as a journey. Space dilation for our traveler means he has not traveled any distance whatsoever. Our traveler is not really a traveler now at all. He was simply in one place, and then he was in another.

 

Except that's not completely accurate either, is it? He was simultaneously at the starting flag and at the finish line, and every point in between. If his ship were a light source and earth was the destination, we would observe exactly that, in a way: The light from his ship at the beginning of his journey would reach earth 100 years years latter, at the same time that the ship arrived. At every point of his journey, the light from his ship would arrive at the same local time for the observer on earth. Perhaps we would see a luminescent line 100 light years long across the sky. (I know I'm ignoring planetary movement, expansion, and a dozen other factors, but that's all beside the point that I'm getting to)

 

So my question is this: What if what we interpret as light speed is not really a velocity at all? Is there any possibility that what we observe as light speed is actually just the only way we can observe infinite velocity; An instantaneous event that we observe as 186000 miles per second because of our own moving position in time-space? So yes, what if time does "pass" in a way, because we pass through time-space, restricting us to observe a simultaneous event of a single particle existing at all points between point A and point B in the dimension of "space" as a journey of c, because of our moving position through the dimension of "time"?

 

I realize that my argument holds about as much water as a Zeno's paradox, and I also understand that it isn't really an argument as much as a thought. So I'm not really asking if this idea is correct. What I'm asking is could there be a scenario where this interpretation would work, and what would it mean about the nature of the universe? Is the idea any more crazy than what we know about quantum mechanics? Truth be told, I see a few similarities.

 

Let me leave you with this: Why does infinite space-time dilation with an infinite amount of energy occur at at c? Why at the speed of light, in particular? Can someone really give me a good reason? I'm not saying that there isn't one, perhaps I just haven't run into it yet. Or more likely I just don't understand it. But either way, I do think that there is more to c than just how fast a light particle happens to travel. And once light speed is surpassed, and our ship begins to travel into the past, doesn't it cease to exist in our local space-time? And when we describe what happens to our traveler as he surpasses light speed, isn't that the same exact way we would try and describe an event that occurred at a speed faster than "instantaneous"?

[md65536]

I'm no expert on relativity but I have spent a lot of time thinking about ideas that sounded eerily similar to your questions, starting about 7 months ago.

Yes there are alternative interpretations that work. I'm trying to write a paper on it, and it's too complicated to try to explain here, and anyway it would belong in the speculations forum. I wrote about it here -- http://www.sciencefo...nce-relativity/ -- but what I wrote is old and too vague and mostly incorrect.

 

The traveler begins his 100 light year journey now at light speed, and maintains it throughout the journey until he reaches his destination. Einstein says, to best of my understanding, that our traveler experiences his journey as an instantaneous event. Furthermore, he does not really experience it as a journey. Space dilation for our traveler means he has not traveled any distance whatsoever. Our traveler is not really a traveler now at all. He was simply in one place, and then he was in another.

 

Except that's not completely accurate either, is it? He was simultaneously at the starting flag and at the finish line, and every point in between.

In the traveler's frame (which isn't really a possible one), the universe is flat, and every point on his journey is the same point. So yes, he's at all those points (ie. at that one single point) at the same time (according to his frame).

 

 

If his ship were a light source and earth was the destination, we would observe exactly that, in a way: The light from his ship at the beginning of his journey would reach earth 100 years years latter, at the same time that the ship arrived. At every point of his journey, the light from his ship would arrive at the same local time for the observer on earth. Perhaps we would see a luminescent line 100 light years long across the sky.

No... if we see light from the start of his journey take 100 years, that means the start of his journey is 100 light years away from us. This can pretty much only happen if he is in a straight line away from us, so we would not see any lateral movement at all. What we might see is something like:

1. We observe that he is 100 light years away. Perhaps we are watching someone wave a flag that tells him to go.

2. Something happens that is a physical impossibility but it doesn't really matter, because it only takes an instant, so we can't describe what we'd see, anyway.

3. He is now here at Earth.

 

It is like saying "Imagine you are watching someone on the moon turn on a flashlight, and at that same instant, you see the light arrive from the flashlight." The moon is about a light-second away, but the flashlight's light (aka the Traveler) arrives at the same time that observations of the start of its journey arrive. But observations travel at the same speed as light (in this case they are light), so you would see the same thing if light traveled instantly, or if it traveled at c, or at any other speed.

 

But other observers would not see the same thing nor the same timing (observation of arrival at the same time as observation of departure). To make it consistent for all observers is a bit more complicated than "light travels instantly".

 

Specifically, an observer who sees the Traveller's journey at all "from the side", eg. so that the path of the journey looks like a line across the sky, will not see the start and end of the journey appearing simultaneous.

 

So my question is this: What if what we interpret as light speed is not really a velocity at all?

If you interpret things so that velocity doesn't apply to light, then what does it apply to?

How do you change things so that velocity still makes sense when speaking of moving matter? How is moving matter so different from light?

 

I realize that my argument holds about as much water as a Zeno's paradox, and I also understand that it isn't really an argument as much as a thought. So I'm not really asking if this idea is correct. What I'm asking is could there be a scenario where this interpretation would work, and what would it mean about the nature of the universe?

If you figure out the math and the logic to make it work, and then figure out what it means, it might tell you some truly fascinating things...

Edited February 7, 2011 by md65536

[alpha2cen]

I have a different way of looking at Einstein than most, that makes faster than light travel possible, without bending any rules. At least, I think I do. Special Relativity says that space-time dilates at near light speed velocities, and that the time slows down for the traveler. As the old story goes, 100 years pass on earth, while only a few years pass for the traveler on the near light speed ship. This is not merely a matter of perception on the part of the either the traveler or the earthbound observer. This is the reality of the space that both parties inhabit. Relativity says that time doesn't just seem to slow down for the traveler, time actually does move slower.

 

As a thought experiment, lets have our traveler make a 100 light year journey from earth to a distant star in our galaxy, at speeds very close to the speed of light. Space-time shortens, or dilates, but only for the traveler, not for us earthbound observers. From our point of view the traveler's journey takes over 100 years to complete. From his point of view, though, only 50 years have passed, and when he comes to his journey's end, he has traveled over 100 light years in 50 years of his time... or, to put it another way, he has traveled, from his point of view, at NEARLY TWICE THE SPEED OF LIGHT.

 

Our thought experiment is not an extreme one. Near light speeds might result in only 10 years passing for the traveler on a 100 light year journey. The scale if infinite, with time coming to a complete stop if actual light speed were possible to obtain. Our traveler looked out the window of his ship and saw the asteroid that marked the halfway point of his trip pass by in just a little over 25 years. The only real question, in my mind, is whether this is a matter of perception on the part of the traveler, or if it is a matter of reality. For those of us on earth to insist that the trip actually took over 100 years is to insist that our reality is correct, and that his is false. Or, to put it another way, he was being effected by Special Relativity, whereas we were... not? Doesn't Special Relativity effect any object that moves through space, even those of us at our computers right now, though at an infinitesimal scale until near light speeds are attained? Can you really say that time is passing for you right now in the exact same way as it is for me?

 

Why is our perception "real" and the traveler's only an illusion? Time, space, and velocity are all relative, aren't they? Is the near light speed traveler actually exceeding the speed of light, at the cost of the dimension of time?

Closed to the light speed the mass becomes infinite. One good thing is we do not worry about the fuel problem, we can go anywhere by using very small amount of fuel. But bad thing is the space craft mass becomes infinite. We have to solve strange infinite problems.

Edited February 17, 2011 by alpha2cen

[Aakash Pandita]

Hello! I am a minor.I did not read all that which is written above.I just wanted to clarify my doubts.I had read that the speed of light is not relative to the observer .I would like to clarify this by stating an example.If a truck is travelling towards me at 10m /sec. and I am running towards it at 1m/sec,I would feel that the truck is running towards me at 9m/sec.But according to the first postulate of relativity,the speed of light is the same for all freely moving observers.Whether I am running towards the light source or running away from it, the speed of light would be the same for me...But I did not understand that how it could be,how the speed of light is different from the truck?

[swansont]

Hello! I am a minor.I did not read all that which is written above.I just wanted to clarify my doubts.I had read that the speed of light is not relative to the observer .I would like to clarify this by stating an example.If a truck is travelling towards me at 10m /sec. and I am running towards it at 1m/sec,I would feel that the truck is running towards me at 9m/sec.But according to the first postulate of relativity,the speed of light is the same for all freely moving observers.Whether I am running towards the light source or running away from it, the speed of light would be the same for me...But I did not understand that how it could be,how the speed of light is different from the truck?

 

It would be 11 m/s, but that's beside the point.

 

It's how electromagnetic waves behave. Maxwell's equations predict this, and relativity explores the ramifications of it.

[IM Egdall]

Hello! I am a minor.I did not read all that which is written above.I just wanted to clarify my doubts.I had read that the speed of light is not relative to the observer .I would like to clarify this by stating an example.If a truck is travelling towards me at 10m /sec. and I am running towards it at 1m/sec,I would feel that the truck is running towards me at 9m/sec.But according to the first postulate of relativity,the speed of light is the same for all freely moving observers.Whether I am running towards the light source or running away from it, the speed of light would be the same for me...But I did not understand that how it could be,how the speed of light is different from the truck?

 

Einstein came up with a formula that works for the truck and the beam of light. It is that speed do not simply add or subtract as Newton thought. Take two speeds, the observer's speed is v. The thing the observer is looking at (whether a truck or beam of light or anything else) is w. The combined speed, W is:

 

W = (v +w) / (1 + vw/c^^2) where c is the speed of light.

 

So if a truck is traveling toward you at v= 10m/sec and you are running towards it at w = 1m/sec; then you do not see the truck moving towards you at W = 9m/sec. If you plug in these values for v and w into the formula above, you get a value of W which is very very slightly less than 9 m/sec. (My calculator doe not have anouhg decimal places to do the actual calculation). So the real answer is something like 8.999999999999 m/sec.

 

And for the light beam, v = 300 million m/sec or c and w = 1m/sec. Then W = 300 million m/sec or c . So it all works out!

Edited March 19, 2011 by I ME