# Speed Of Light Vs. Time Dilation.

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### #1 ikester7579

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Posted 13 January 2010 - 02:40 AM

Time dilation is where the faster you travel, the slower time passes. There have been several experiments done where one clock or watch is sync to another. And one person gets on a plane and travels around the world. While the other stays on the ground. Upon the two meeting up again, they find that the clock or watch from the person on the plane is no longer in sync with the time of the person on the ground. The time from the person on the plane has moved slower, because of the travel speed (time dilation).

It is also believed that there is a speed to where when reached, time just stops (A infinity or eternal time situation).

Being that the speed of light is 299 792 458 m / s. If one could put a time device on a light photon. What would be the time difference between the light photon travelling that fast? And us on a planet not travelling that fast?

So not factoring in time dilation at the speed of light, are we really measuring the correct speed of light? Because if time moves more slowly for the photon, but faster for us, how could we actually claim that light travels at a certain speed?

Example:

Based on what time dilation does to time...

If a runner runs around a track and is timed by a slower and faster stop watch. He will have 2 different times. And if his speed is determined by time to travel the distance he ran, he will have two different speeds.

1) Now apply that to how the light photon speed slows down time and measure by that clock.
2) Measure speed by our time where we are not moving, and measure by that clock.

What we will have is two different times, which works out to two different speeds for light travel. So because of time dilation, speed becomes a preception of how it's measured according to how fast you are travelling.

Example 2:

Light takes 8.3 minutes to reach the earth from the sun. But would the prospective of how fast light travels be the same for the light photon if a time device was placed upon it measuring it's time dilation that existed at that speed of travel?

1) Our time measure 8.3 minutes.
2) Time dilation at the speed of the photon may measure 50% or less of the time we measure.

So which would be correct?
1) Our preception of light speed without time dilation?
2) Or light speed with time dilation factored in?

And a theory to ponder.

Since there is proof of time dilation. What if speed in space has dimension barriers of time? Kinda like breaking the sound barrier here on earth. What if there are time barriers that reveal different time dimensions?

So instead of mach one with sound. We would have time dimension one at a certain speed. Double that and you would have time dimension 2. If doubling it works like the sound barrier does.

### #2 skeptic

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Posted 13 January 2010 - 05:02 AM

Time dilation is where the faster you travel, the slower time passes. There have been several experiments done where one clock or watch is sync to another. And one person gets on a plane and travels around the world. While the other stays on the ground. Upon the two meeting up again, they find that the clock or watch from the person on the plane is no longer in sync with the time of the person on the ground. The time from the person on the plane has moved slower, because of the travel speed (time dilation).

For example the Hafele-Keating-Experiment showed this.

It is also believed that there is a speed to where when reached, time just stops (A infinity or eternal time situation).
Being that the speed of light is 299 792 458 m / s. If one could put a time device on a light photon. What would be the time difference between the light photon travelling that fast? And us on a planet not travelling that fast?

For the photon there is no time progression. The time a photon needs to travel a certain distance is FOR THE PHOTON zero.

So not factoring in time dilation at the speed of light, are we really measuring the correct speed of light? Because if time moves more slowly for the photon, but faster for us, how could we actually claim that light travels at a certain speed?

In all frames of reference the speed of light is always the same and we can measure it to be the same. The exception would be if we could measure it in the reference frame of the photon itself. There the SPEED of light would be meaningless since there is no time.

Example:

Based on what time dilation does to time...

If a runner runs around a track and is timed by a slower and faster stop watch. He will have 2 different times. And if his speed is determined by time to travel the distance he ran, he will have two different speeds.

1) Now apply that to how the light photon speed slows down time and measure by that clock.
2) Measure speed by our time where we are not moving, and measure by that clock.

What we will have is two different times, which works out to two different speeds for light travel. So because of time dilation, speed becomes a preception of how it's measured according to how fast you are travelling.

Ok, understanding your example correctly: you have two clocks or stop watches. To measure time differently (to be faster or slower) they have to be moving at different speeds. Now both clocks measure the time a photon travels a distinct distance. Both measure the speed of light to be the same but they measure a different distance for the light to travel between the two points and for both the photon to reach the goal is not simultaneously.

Example 2:

Light takes 8.3 minutes to reach the earth from the sun. But would the prospective of how fast light travels be the same for the light photon if a time device was placed upon it measuring it's time dilation that existed at that speed of travel?

1) Our time measure 8.3 minutes.
2) Time dilation at the speed of the photon may measure 50% or less of the time we measure.

So which would be correct?
1) Our preception of light speed without time dilation?
2) Or light speed with time dilation factored in?

the time for the photon would be non-existent. Both would be correct. To understand relativity you have to rethink the common concept of simultaneity

And a theory to ponder.

Since there is proof of time dilation. What if speed in space has dimension barriers of time? Kinda like breaking the sound barrier here on earth. What if there are time barriers that reveal different time dimensions?

So instead of mack one with sound. We would have time dimension one at a certain speed. Double that and you would have time dimension 2. If doubling it works like the sound barrier does.

The speed of light could really be considered a barrier but a barrier which is not possible to break because you get into really big paradoxons like arriving before leaving and hindering yourself leaving. What would be then? Would you exist twice? You run into really big problems when you consider to break the speed of light barrier.

### #3 ikester7579

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Posted 13 January 2010 - 05:15 AM

For example the Hafele-Keating-Experiment showed this.
For the photon there is no time progression. The time a photon needs to travel a certain distance is FOR THE PHOTON zero.
In all frames of reference the speed of light is always the same and we can measure it to be the same. The exception would be if we could measure it in the reference frame of the photon itself. There the SPEED of light would be meaningless since there is no time.
Ok, understanding your example correctly: you have two clocks or stop watches. To measure time differently (to be faster or slower) they have to be moving at different speeds. Now both clocks measure the time a photon travels a distinct distance. Both measure the speed of light to be the same but they measure a different distance for the light to travel between the two points and for both the photon to reach the goal is not simultaneously.
the time for the photon would be non-existent. Both would be correct. To understand relativity you have to rethink the common concept of simultaneity

The barrier to break may do something totally different to time then what you think. If time becomes infinite at some point, then one part of the time equation maybe eliminated.

Past-present-future. Are the there parts of time. But when time becomes infinite, then you are no longer present in time because there is no way to measure present time in infinite time.

So infinite time would be: Past-future. No present. This would solve you problem mentioned here:

The speed of light could really be considered a barrier but a barrier which is not possible to break because you get into really big paradoxons like arriving before leaving and hindering yourself leaving. What would be then? Would you exist twice? You run into really big problems when you consider to break the speed of light barrier.

Because when you eliminate present time, you cannot hinder yourself. There cannot be two of you. Because you are everywhere in time, the problems of time are no longer a factor. That is what would make it infinite.

### #4 skeptic

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Posted 13 January 2010 - 05:45 AM

The barrier to break may do something totally different to time then what you think. If time becomes infinite at some point, then one part of the time equation maybe eliminated.

Where and how does time become infinite? Time for photons is zero and that is very finite.

Past-present-future. Are the there parts of time. But when time becomes infinite, then you are no longer present in time because there is no way to measure present time in infinite time.

I dont understand what you mean by infinite time. What makes it infinite?

So infinite time would be: Past-future. No present. This would solve you problem mentioned here:
Because when you eliminate present time, you cannot hinder yourself. There cannot be two of you. Because you are everywhere in time, the problems of time are no longer a factor. That is what would make it infinite.

Sorry, you have to rephrase it because i dont get it. How could you get rid of "present"? You ARE everywhere in time, maybe at some time only in particles and maybe ghostlike floating somewhere but you are always as long as always lasts.

### #5 ikester7579

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Posted 13 January 2010 - 05:56 AM

Where and how does time become infinite? Time for photons is zero and that is very finite.
I dont understand what you mean by infinite time. What makes it infinite?

Sorry, you have to rephrase it because i dont get it. How could you get rid of "present"? You ARE everywhere in time, maybe at some time only in particles and maybe ghostlike floating somewhere but you are always as long as always lasts.

If time stops to where one can see it "all" from beginning to end (past-future), where in time would you exist if that happened?

### #6 skeptic

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Posted 13 January 2010 - 06:08 AM

If time stops to where one can see it "all" from beginning to end (past-future), where in time would you exist if that happened?

If time would stop this very moment, there would be no progress any more since progress needs time. You existed in the time you lived and maybe before in some way from the beginning of time. How could you see "all" from beginning to end? since when time stops you only exists at that very moment.
The only concept to see "all" is to exist outside of space and time in some other form of dimension or something and there has to be some mechanisms to "watch" the things inside space and time. If something like that is possible but this is highly speculative.
If you like these concepts with multiple dimensions and our universe being a "brane" you have to look into string theory especially M-theory.
I struggle sometimes enough with our 4 space-time dimensions.

### #7 Guest_Darkness45_*

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Posted 13 January 2010 - 06:36 AM

Time dilation...

Are you suggesting that due to time dilation (that is proven), light moves at an infinity speed, and not a finite speed?

And a theory to ponder.

Since there is proof of time dilation. What if speed in space has dimension barriers of time? Kinda like breaking the sound barrier here on earth. What if there are time barriers that reveal different time dimensions?

So instead of mach one with sound. We would have time dimension one at a certain speed. Double that and you would have time dimension 2. If doubling it works like the sound barrier does.

That is a very interesting question. I know you don't agree with the big bang theory, but if it is correct, then the inflation model is a valid explanation for what we see, which also means that objects can break the speed of light barrier.

### #8 skeptic

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Posted 13 January 2010 - 07:04 AM

Are you suggesting that due to time dilation (that is proven), light moves at an infinity speed, and not a finite speed?
That is a very interesting question. I know you don't agree with the big bang theory, but if it is correct, then the inflation model is a valid explanation for what we see, which also means that objects can break the speed of light barrier.

How could an object break the speed of light barrier? Thats not possible except maybe for some exotic particles about which where some speculation but were never detected.
A photon in itÃƒâ€šÃ‚Â´s own reference frame is moving at an infinite speed since time is non-existent for it.

### #9 Guest_Darkness45_*

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Posted 13 January 2010 - 07:38 AM

How could an object break the speed of light barrier? Thats not possible except maybe for some exotic particles about which where some speculation but were never detected.
A photon in itÃƒâ€šÃ‚Â´s own reference frame is moving at an infinite speed since time is non-existent for it.

It is not so much the object itself, but that space itself is expanding so rapidly that, relative to us (as all motion is relative), the object is going faster than the speed of light. The inflation theory predicts this, which is based on the homology of the universe as well as it being relatively flat.

### #10 skeptic

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Posted 13 January 2010 - 08:00 AM

It is not so much the object itself, but that space itself is expanding so rapidly that, relative to us (as all motion is relative), the object is going faster than the speed of light. The inflation theory predicts this, which is based on the homology of the universe as well as it being relatively flat.

I know, i know, I took several classes in astrophysics. Space expanding is something completely different than the in space embedded objects moving themselves, I just misunderstood you.

### #11 Scanman

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Posted 13 January 2010 - 11:40 AM

Time dilation is where the faster you travel, the slower time passes. There have been several experiments done where one clock or watch is sync to another. And one person gets on a plane and travels around the world. While the other stays on the ground. Upon the two meeting up again, they find that the clock or watch from the person on the plane is no longer in sync with the time of the person on the ground. The time from the person on the plane has moved slower, because of the travel speed (time dilation).

It is also believed that there is a speed to where when reached, time just stops (A infinity or eternal time situation).

Being that the speed of light is 299 792 458 m / s. If one could put a time device on a light photon. What would be the time difference between the light photon travelling that fast? And us on a planet not travelling that fast?

So not factoring in time dilation at the speed of light, are we really measuring the correct speed of light? Because if time moves more slowly for the photon, but faster for us, how could we actually claim that light travels at a certain speed?

Example:

Based on what time dilation does to time...

If a runner runs around a track and is timed by a slower and faster stop watch. He will have 2 different times. And if his speed is determined by time to travel the distance he ran, he will have two different speeds.

1) Now apply that to how the light photon speed slows down time and measure by that clock.
2) Measure speed by our time where we are not moving, and measure by that clock.

What we will have is two different times, which works out to two different speeds for light travel. So because of time dilation, speed becomes a preception of how it's measured according to how fast you are travelling.

Example 2:

Light takes 8.3 minutes to reach the earth from the sun. But would the prospective of how fast light travels be the same for the light photon if a time device was placed upon it measuring it's time dilation that existed at that speed of travel?

1) Our time measure 8.3 minutes.
2) Time dilation at the speed of the photon may measure 50% or less of the time we measure.

So which would be correct?
1) Our preception of light speed without time dilation?
2) Or light speed with time dilation factored in?

And a theory to ponder.

Since there is proof of time dilation. What if speed in space has dimension barriers of time? Kinda like breaking the sound barrier here on earth. What if there are time barriers that reveal different time dimensions?

So instead of mach one with sound. We would have time dimension one at a certain speed. Double that and you would have time dimension 2. If doubling it works like the sound barrier does.

A photon under any and all circumstances, only travels at one speed 'c'.

TR and light speed is a very complicated subject, and has to be contemplated in terms of spacetime.

It is not as simple as going in a straight line from A to B...there is an angular vector of time that changes based on relative speed.

Think of space and time as sharing a common set resource of 'speed' (the speed of light).

An object at rest is only moving through time, as it begins to accelerate, speed is diverted from movement through time to movememnt through space...time slows down. As the objects speed approaches and reaches the speed of light, movement through time comes to a halt.

The combined speed of an object's motion through space and it's motion through time is alwasy precisely equal to the speed of light.

Here's a few words from Brian Greene's latest, The Fabric of the Cosmos.

From page 46 on relativity:

...These assumptions about space and time comport with our daily experiences and for that reason are the basis of our commonsense conclusion that light should appear to travel more slowly if we run after it. To see this, imagine that Bart, who's just received a new nuclear-powered skateboard, decides to take on the ultimate challenge and race a beam of light. Although he is a bit disappointed to see that the skateboard's top speed is only 500 million miles per hour, he is determined to give it his best shot. His sisterLisa stands ready with a laser; she counts down from 11 (her hero Schopenhauer's favorite number) and when she reaches 0, Bart and the laser light streak off into the distance. What does Lisa see? Well, for every hour that passes, Lisa sees the light travel 670 million miles while Bart travels only 500 million miles, so Lisa rightly concludes that the light is speeding away from Bart at 170 million miles per hour. Now let's bring Newton into the story. His ideas dictate that Lisa's observations about space and time are absolute and universal in the sense that anyone else performeing these measurements would get the same answers. To Newton, such facts about motion through space and time were as objective as two plus two equaling four. According to Newton, then, Bart will agree with Lisa and will report that the light beam was speeding away from him at 170 million miles per hour.

But when Bart returns, he doesn't agree at all. he dejectedly claims that no matter what he did--he saw the light speed away at 670 million miles per hour, not a bit less. And if for some reason you don't trust Bart, bear in mind that thousands of meticulous experiments carried out during the last hundred years, which have measured the speed of light using moving sources and receivers, support his observations with precision.

From page 48 on relativity:

"We are used to the fact that objects can move through space, but there is another kind of motion that is equally important: objects also move through time. Right now, the watch on your wrist and the clock on the wall are ticking away, showing that you and everything around you are relentlessly moving through time, relentlessly moving from one second to the next and the next. Newton thought that motion through time was totally separate from motion through space - he thought these two kinds of motion had nothing to do with each other. But Einstein found that they are intimately linked. In fact, the revolutionary discovery of special relativity is this: When you look at something like a parked car, which from your viewpoint is stationary - not moving through space, that is - all off its motion is through time. The car, its driver, the street, you, your clothes are all moving through time in perfect synch: second followed by second, ticking away uniformly. But if the car speeds away, some of its motion through time is diverted into motion through space. And just as Bart's speed in the northward direction slowed down when he diverted some of his northward motion into eastward motion, the speed of the car through time slows down when it diverts some of its motion through time into motion through space. This means that the car's progress through time slows down and therefore time elapses more slowly for the moving car and its driver than it elapses for you and everything else that remains stationary.

That, in a nutshell, is special relativity."

Peace

### #12 Otto13

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Posted 13 January 2010 - 12:09 PM

Are you suggesting that due to time dilation (that is proven), light moves at an infinity speed, and not a finite speed?
That is a very interesting question. I know you don't agree with the big bang theory, but if it is correct, then the inflation model is a valid explanation for what we see, which also means that objects can break the speed of light barrier.

I think inflation suggests that space itself expanded faster than light. Somehow this is supposed to be possible although the theory does not allow anything with mass to go faster than the speed of light.

Easy, right?

### #13 ikester7579

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Posted 13 January 2010 - 12:13 PM

I'm not trying to say that light speed is different from "our prospective". I'm trying to relay that there maybe more than one prospective to look at it from because of time dilation.

Example:
The earth's orbit speed around the sun is: 107218 km/h.
Rotation or spin speed is around 1,674.4 km/h.

Since we are orbiting the sun and spinning, does not that effect our preception of the speed of light because of time dilation compared to maybe the preception if it were taken on another planet that orbits and rotates at a different speed?

If time dilation is true, and there is evidence for this. Then our orbit and spin effects everything we measure and see. If it don't, as I know some here will imply, then time dilation does not work because it has to apply to "everything" that moves. Denial of this does not make it work. And one cannot choose which objects moving this will effect. And we are moving and spining through space, are we not?

Another theory to ponder....

We are moving through space (orbiting the sun). And we are also spinning (rotating). I wonder if the travel through space is like one form of time dilation, while spinning in a certain direction may add or take away from the time dilation of our current orbit speed?

1) Our movement through space = this amount of time dilation.
2) Rotation in one direction may = adding to it.
3) While rotation in the other direction may = taking away from it.

In fact, our planet movement and spin may create it's own time dimension for all life that lives upon it. And the conbination of our speed around the sun, and our rotation may just determine this.

### #14 Scanman

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Posted 13 January 2010 - 12:25 PM

I think inflation suggests that space itself expanded faster than light.

Otto,

Do you have a source for this?

Thanks

Peace

### #15 Otto13

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Posted 13 January 2010 - 01:06 PM

Otto,

Do you have a source for this?

Thanks

Peace

No, I do not, sorry. It is something I recall reading/hearing with respect to the inflationary phase of the universe very early on.

Perhaps someone else can direct you better than I can on this issue.

### #16 Guest_Darkness45_*

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Posted 13 January 2010 - 02:00 PM

Otto,

Do you have a source for this?

Thanks

Peace

While I don't have an in-depth source or anything (that's the problem with school these days, you get a lot of random knowledge but have no idea where to find it on the internet or in a book), here is an expert from the wiki page Metric expansion of space, just so you know were not just making the whole thing up.

"While special relativity constrains objects in the universe from moving faster than the speed of light with respect to each other, there is no such theoretical constraint when space itself is expanding. It is thus possible for two very distant objects to be moving away from each other at a speed greater than the speed of light (meaning that one cannot be observed from the other). The size of the observable universe could thus be smaller than the entire universe.

It is also possible for a distance to exceed the speed of light times the age of the universe, which means that light from one part of space generated near the beginning of the Universe might still be arriving at distant locations (hence the cosmic microwave background radiation). These details are a frequent source of confusion among amateurs and even professional physicists."

This is a real possibility with the inflation theory, as it solves problems related to the homology of the universe and it's flatness along with magnetic monopoles. As the universe continues to expand exponentially, eventually we will see nothing outside of our own galaxy, because the space is expanding so rapidly that the object's light is not fast enough to reach us.

### #17 skeptic

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Posted 14 January 2010 - 03:41 AM

[...]
We are moving through space (orbiting the sun). And we are also spinning (rotating). I wonder if the travel through space is like one form of time dilation, while spinning in a certain direction may add or take away from the time dilation of our current orbit speed?

First you have to understand the concept of "Inertial frames of reference". Time dilation could only happen if you compare the "Inertial frame of reference" of a spinning, moving etc body to some other "Inertial frame of reference" of maybe another body. Say somebody on the moon is on another Inertial frame of reference than somebody here on earth, because of different gravitation and different moving speeds. Both have different time frames compared to each other but in all and every reference frame the speed of light in vacuum is always the same.

1) Our movement through space = this amount of time dilation.
2) Rotation in one direction may = adding to it.
3) While rotation in the other direction may = taking away from it.

In fact, our planet movement and spin may create it's own time dimension for all life that lives upon it. And the conbination of our speed around the sun, and our rotation may just determine this.

What you call another "time dimension" is in physics another "Inertial frame of reference". Everything you do causing you to accelerate or deccelerate or move at another speed changes your Inertial frame of reference. Also climbing up a mountain or flying up on a plane or whatever. The time dilation effects are miniscule for these actions at our speeds but measurable. We only would recognize them at very fast speeds but always compared to an object slower or even more faster.

### #18 AFJ

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Posted 14 January 2010 - 07:15 PM

First you have to understand the concept of "Inertial frames of reference". Time dilation could only happen if you compare the "Inertial frame of reference" of a spinning, moving etc body to some other "Inertial frame of reference" of maybe another body. Say somebody on the moon is on another Inertial frame of reference than somebody here on earth, because of different gravitation and different moving speeds. Both have different time frames compared to each other but in all and every reference frame the speed of light in vacuum is always the same.
What you call another "time dimension" is in physics another "Inertial frame of reference". Everything you do causing you to accelerate or deccelerate or move at another speed changes your Inertial frame of reference. Also climbing up a mountain or flying up on a plane or whatever. The time dilation effects are miniscule for these actions at our speeds but measurable. We only would recognize them at very fast speeds but always compared to an object slower or even more faster.

Just an example of this. If there are any "trekies" out there, did you see the episode where several of the Enterprise crew became very fast? So fast it appeared everyone else was almost standing still. They could see the "slow crew"--meanwhile the slow crew thought the "fast crew" had disappeared.

Point being--for a fast crew member to watch a "slowie" move his arm an inch it would take a half an hour. But to a slowie it only took a half a second!

This then raises the question "Is time a just a mental perception?" A perception of the one who is in his "inertial frame of reference".

In other words, is there absolute time, despite relativity? Does light travel a certain absolute distance in the while I blink my eye? Or does the distance change according to what IFOR I am in?

### #19 skeptic

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Posted 15 January 2010 - 03:36 AM

Yes, what is time. Thats one of the biggest questions in physics. Since Einstein time is just another dimension added to the three space dimensions. But why is it only possible to go in one direction?
A good way to visualize the concept of spacetime is to think it as one four dimensional space where EVERYTHING is moving at the speed of light. Photons move only through space but not through time (in their "perception") and everything else goes in a fraction through the normal space and through time.
We go through time at the speed of light and when we move a fraction of this speed is not through time but through space.
All relatively compared to others.

Well, in modern physics there is nothing like absolute time. I would define time as the measurable "distance" between two events. You measure the distance with recurring events of equal distances like the oscillation of a quartz. but all these distances are relative between objects of different speed.

Light is a very big exception. The speed is the same in all IFOR but the distances change depending on your speed compared to somebody elses speed.

Just an example of this.  If there are any "trekies" out there, did you see the episode where several of the Enterprise crew became very fast?  So fast it appeared everyone else was almost standing still.  They could see the "slow crew"--meanwhile the slow crew thought the "fast crew" had disappeared.

Point being--for a fast crew member to watch a "slowie" move his arm an inch it would take a half an hour.  But to a slowie it only took a half a second!

This then raises the question "Is time a just a mental perception?"  A perception of the one who is in his "inertial frame of reference".

In other words, is there absolute time, despite relativity?  Does light travel a certain absolute distance in the while I blink my eye?  Or does the distance change according to what IFOR I am in?

### #20 Guest_TeslaNick_*

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Posted 08 February 2010 - 10:21 PM

Or does the distance change according to what IFOR I am in?

It depends on what you mean by this.

Let's imagine that you split yourself into two people, telepathically linked by some sort of quantum entanglement. Any thought AFJ-A has, AFJ-B also has, instantaneously. In this way your two selves can be thought to be communicating.

Now let's imagine that AFJ-A hops on a train that promptly sets off from the station at a relative speed of 0.866c, while AFJ-B remains on the station. Your two selves are going to perform an experiment on how far light travels based on your frame of reference.

I picked 0.866c because it means your relative time dilation would be 2. Every second that passes for AFJ-A, two seconds pass for AFJ-B. Ignore for the moment the fact that AFJ-A's thoughts would become suddenly very comically slurred. When AFJ-A measures the speed of light travelling in the direction of the train's movement (i.e. from the rear of the train to the front of the train), he measures ~300 000 km/s. When AFJ-B measures the exact same photons he will measure... ~300 000 km/s. Intuitively this doesn't make sense: how can an object move two different speeds for two different observers? AFJ-A should have measured C as 150 000 km/s! The answer is in their differing perceptions of time.

Under relativity, there is no universal "now", and there is no universal speed at which a frame of reference moves "future-ward".

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