Trouble understanding Time Dilation

[nd]

First, before I get to my questions, I will explain the basics of time dilation as I understand it (should be pretty accurate given that I've recently been reading about it).

Time Dilation is commonly known as a phenomenon due to consequences of special relativity. The effect is that the time interval measured by an observer moving with respect to a clock is longer than the time interval measured by the observer at rest with respect to the clock. For example, if two people had a stop-watch and started them at the same time, with one being on a spaceship moving at velocities close to the speed of light and the other person at rest on earth, when they land the person's clock who was on the spaceship will show less time elapsed than the stationary observer.

The most common thought-experiment used to illustrate how this concept can be is a variation of the following. Consider a moving vehicle with a mirror mounted on the ceiling. Let d equal the distance from the floor to the ceiling. There is a person in the moving vehicle and an observer at rest outside the vehicle. The person in the vehicle sends a light pulse straight up toward the mirror and it reflects and hits the floor of the vehicle.

For the person in the moving vehicle, it takes time t' for this to happen. t' can easily be determined using the definition of speed (speed = distance/time), so t' = (2 * d) / c, where c is the speed of light.

However, for the observer outside the vehicle, things are different because the light pulse appears to take a different path. Since the vehicle is moving, the light pulse's path will appear triangular. See the following (primitive with formatting likely screwed up) ASCII illustration below.


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So even though the light appears to go straight up and back down to the person inside the moving vehicle, it appears to reflect at an angle to the outside observer. The consequence of this is that the light appears to have traveled a further distance to the outside observer than from inside, since what was a distance of only 2*d is now dependant on how far the vehicle traveled (to do the geometric calculation for the distance the pulse traveled).

Since the distance traveled to the observer is larger, and time = distance/speed, and the speed of light is constant, it is concluded that the time elapsed according to the observer is longer than the time elapsed by the person in the vehicle. That's time dilation. It's widely accepted and has been proven with a few types of experiments (I've read about the Muons experiment and also the ones with the atomic clocks flying in jets).

Now, on to my questions.

Although I've kinda-sorta understood time dilation and relativity for many years (initially learned in High School Physics, and went more in depth in College), and could do math/physics problems by simply accepting the concepts as truth, I have a hard time buying into it after looking back at it.

My source of disbelief half comes from the fact that it contradicts with what seems logical to me, and half comes from the "sketchy" nature of experiments that prove it (many variables involved, results that weren't perfect although did indicate that time dilation was likely the cause due to variations of ~60 nanoseconds or so).

When reading the thought-experiment from above, my personal inclination is to believe that the time elapsed is in fact the same for both observers. What seems logical to me, is that the speed of light to the person in the vehicle would appear slower, although it is actually the same speed of light as always. The reason it would appear slower is because, as noted by the observer, the light is not taking a path straight up and back down. Now, if we could say that the outside observer was in a absolute reference point of rest, the path he observes is the correct one (the preferred frame of reference), so the distance the light travels is absolute and the time it takes to get there is absolute. The speed of light is always the same. The only source of variation between the two observers is the perceived speed of light depending on their frame of reference. To the outside observer (if he were at an absolute reference point of rest), the speed of the light would be perceived as 1*c. Any other frame of reference would result in a perceved speed of k*c, where k < 1 (so a slightly slower speed).

This seems completely logical to me, although it does contradict what I've learned. The reason it seems logical to me is that I think of the universe in terms of quantifiable "points", like you would have in a computer 3D world. I assert that there is a specific and absolute number of "points" the light has moved in its path from the floor to the ceiling and back. This number of points does not change, and the speed of light is the maximum of 1 point per time unit. Given this, time dilation is non-existant.

So, that's my understanding of time dilation and why I'm having trouble understanding/accepting it. Most likely, I'm not some genius who has just proved time dilation invalid, but rather I'm making in an error in 1) my understanding of what time dilation is, or 2) my reasoning for the contradiction.

Thanks in advance to anyone who can help clear things up for me.

 

[mygumballs]

i used to have that same misconception that space is made up of a specific number of points. i believed space could be expressed as a type of 3d plot that never changed. but this way of thinking will greatly mislead you.

what i had to understand, and you do too, is that there is no absolute frame of reference in the universe. there is no absolute volume of points in space ( which is quite similar to the old notion of space being filled with an imaginary substance called ether). you can never exactly measure time, length, speed, charge, potential, energy, or anything. this is because everything is relative. i know you know this already, and so did i. but it wasn't untill i fully understood and just thought about it that i finally said "oh...i guess i was wrong...."

also, you have to think of the universe as a 4d space. that'll completely do away with teh "absolute points" theory since the density of these points will have to be taken into account.

...for some reason, i don't think i did a good job with getting my point across. oh well, just don't think i'm some kid talking out of his ass, please. i've read MOST of stephen hawkings "a brief history of time"...

 

[rgwalt]

Looking at the universe as being a 3D set of finite points is an incorrect viewpoint. There are an infinite number of points in the universe, with an an infinte number of points between two given locations. Furthermore, your arguement relies on the speed of light not being constant. You say that it is constant, and then say there is an "observable" speed of light that can be different between two reference frames. This is the flaw in your logic. The speed of light is uniform no matter what reference frame you are in. Get this... You are standing next to a set of train tracks. A train passes you going really fast (it doesn't matter how fast, but lets say 0.5c). The moment that you and the train are lined up both you and the train turn on laser beams heading forward. Now, even though the train is going 0.5c relative to you, the ends of the beams even with each other. Seems wrong, but it isn't. Whats even more strange is that both reference frames measure their own beams and the beams of the other reference frame as going at the speed of light. Thats some strange stuff, but it has been proven experimentally that the speed of light is constant no matter the reference frame. By talking about an observable speed of light you are violating the founding assumption of the moving photon clock proof.

So, yeah, there you go. Another way to look at the situation is that you can physically measure the distances, times, and the velocity of the moving photon clock. Something has to bend between the two reference frames... either distance, time, or the speed of light. Since the distances measured are all perpendicular to the direction of travel, and since the speed of light is constant no matter what reference system you are in, then time must be compressed.

Now, ready for length contraction?

Ryan

 

[heliomphalodon]

Special Relativity is based upon two postulates: (the following is a direct quote from Einstein)

1) The laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems of coordinates in uniform translatory motion.
2) Any ray of light moves in the "stationary" system of coordinates with determined velocity c, whether the ray be emitted by a stationary or by a moving body.

By "stationary" Einstein means simply "Newtonian" -- not absolute.

Why should we accept Einstein's postulates (and thereby reject your intuition that it is the speed of light that varies, not the time interval)?
Simple -- experimental results support Einstein's position. Time dilation is a measured fact. It's hard to get used to, as are the loss of "simultaneity" of events and contraction of lengths -- but that's only because we don't generally experience these effects in a noticable way.

Since light is postulated to move with velocity c, time intervals are defined in terms of the speed of light -- not the other way around. The evidence in Einstein's favor is very, very strong.

 

[rgwalt]

Nice post helio... OK, time to break out something really funky about length contraction. OK, here is the basic idea... objects that are moving at high velocities "shrink" in the direction of motion. For instance, a 20 ft pole appears to be 10 ft long by a non-moving observer when moving at 0.866c (not positive on this number). Seems weird, but straightforward, right? Now think about this... A person riding on said pole moving at 0.866c measures the pole as being 20 ft long. Afterall, he isn't moving with respect to the pole. Now, lets say this pole is heading for a carport (a garage without walls). Now, lets say this carport is 10 feet deep, so the 20 ft pole couldn't fit inside if it wasn't moving. Now, realize that the pole moving at 0.866c is only 10 ft long, so it should fit inside the carport perfectly for an instant. Now here is the problem... Since the pole is moving with constant velocity, you can also say that the carport is moving at the pole at 0.866c, and the guy riding the pole sees a garage that is only 5 ft deep. As far as the guy on the pole is concerned, there is no way that the 20 ft pole he is riding could fit in the 5ft deep carport coming at him.

Both reference frames are completely valid. What happens? Does the pole fit in the carport for an instant, or does at least 15ft of it stick out? Do two different reference frames observe different events occuring in the same time and place in space? What the dilly-o?

Ryan

 

[nd]

Originally posted by: rgwalt
Looking at the universe as being a 3D set of finite points is an incorrect viewpoint. There are an infinite number of points in the universe, with an an infinte number of points between two given locations.

Yes, I suspected that this assumption is where I went wrong.. but anything else is hard for my puny mind to imagine.

Furthermore, your arguement relies on the speed of light not being constant. You say that it is constant, and then say there is an "observable" speed of light that can be different between two reference frames. This is the flaw in your logic. The speed of light is uniform no matter what reference frame you are in.

There is no flaw here in my logic as far as I can tell. I said that the perceived speed of light varies, but the actual speed it traveled is constant... because to the person perceiving it to be slower, he didn't realize that it actually traveled more distance -- so the speed is still constant. No flaw here.

Get this... You are standing next to a set of train tracks. A train passes you going really fast (it doesn't matter how fast, but lets say 0.5c). The moment that you and the train are lined up both you and the train turn on laser beams heading forward. Now, even though the train is going 0.5c relative to you, the ends of the beams even with each other. Seems wrong, but it isn't.

Actually, I readily accept that the beams would be even with each other. This seems "right" to me (perhaps out of coincidence), since in terms of 3D points the maximum it can travel is always 1 point per unit time. They both are, and are as such even with each other. However, I don't yet accept that this implies Time Dilation (and length contraction for that matter).

By talking about an observable speed of light you are violating the founding assumption of the moving photon clock proof.

Hmm.. maybe you are right about this. But I think there's also the possibility that what I mean by observable speed of light is different from what you're thinking. I'm thinking of observable speed of light strictly in terms of the calculated speed based on distance and time. I'll try to read about that moving photon clock proof, haven't heard of it.

 

[nd]

I did some reading and found out that Michelson and Morley had the same idea I did. When they tried to prove it by measuring differences in their perceived speed of light (in a set of very complex experiments where they desperately tried to get the results they were expecting), they were unable to find any. So that proves my original thoughts to be wrong.

Along came Einstein, and his Theory of Special Relativity explains Michelson and Morley's results. His theories have been (as one of you has noted) tested and match well in explaining reality.

However, after thinking about it even more, I have managed to explain to myself why Michelson and Morley didn't measure a difference in the perceived speed of light, without any time dilation being necessary.

Once again, I'm going to think in terms of discrete points of space. Yes, I realize that perhaps this is a huge flaw.

In the thought-experiment mentioned in my original post, I asserted that because the actual (in relation to an absolute frame of reference) distance traveled by the light pulse was longer than d', the perceived speed of light would be slightly slower. However, this is only true if you think about the speed of light in terms of net distances between points. When I thought about this again, I considered it a flaw to look at it this way. Rather, remember that the speed of light is the maximum possible speed of 1 point per unit time. This means that for every unit time when the vehicle is moving, the light pulse will move one point up/down toward/away from the mirror. What is the consequence of this? Although the distance of the path between the points on the floor and ceiling are greater if the vehicle is moving, the number of points in the pulse's path is the same in both cases!

See this illustration for my explanation of why no difference in the speed of light was measured.

So yeah, now that I've thought about it more I'm more confused than ever. I don't see how time dilation would necessarily have to exist. To some of you who insist on just citing Einstein's postulates, although I appreciate the thought, that's not really what I'm interested in. I already understand what the theories are and what they imply. What I'm trying to understand here is how this can be.

 

[Haircut]

I really don't think you can make the assumption that space behaves that way.
One of the postualtes of special relativity is that all inertial reference frames are equivalent. Once you throw that away and assume that there is one 'superior' reference frame then you can't expect things such as time dilation to work.

Space could well be discrete (look up Planck Length), but at the level we would have lots of quantum effects coming into play, so I don't think it's as clean cut as you would like to believe.
There are some things that the human mind cannot comprehend and we have to come to terms with that and just accept that it works.
For an example try thinking of two planes intersecting at a single point (it's perfectly possible in 4-d space.)

 

[heliomphalodon]

Originally posted by: rgwalt
Nice post helio... OK, time to break out something really funky about length contraction. OK, here is the basic idea... objects that are moving at high velocities "shrink" in the direction of motion. For instance, a 20 ft pole appears to be 10 ft long by a non-moving observer when moving at 0.866c (not positive on this number). Seems weird, but straightforward, right? Now think about this... A person riding on said pole moving at 0.866c measures the pole as being 20 ft long. Afterall, he isn't moving with respect to the pole. Now, lets say this pole is heading for a carport (a garage without walls). Now, lets say this carport is 10 feet deep, so the 20 ft pole couldn't fit inside if it wasn't moving. Now, realize that the pole moving at 0.866c is only 10 ft long, so it should fit inside the carport perfectly for an instant. Now here is the problem... Since the pole is moving with constant velocity, you can also say that the carport is moving at the pole at 0.866c, and the guy riding the pole sees a garage that is only 5 ft deep. As far as the guy on the pole is concerned, there is no way that the 20 ft pole he is riding could fit in the 5ft deep carport coming at him.

Both reference frames are completely valid. What happens? Does the pole fit in the carport for an instant, or does at least 15ft of it stick out? Do two different reference frames observe different events occuring in the same time and place in space? What the dilly-o?

Ryan

I can't really deal with this apparent paradox in full, but I'll venture to say that the confusion arises because of lack of simultaneity. We're used to situations where the front end of the pole reaches the front end of the carport at the same time that the rear end of the pole reaches the rear end of the carport. That's not the case when relativistic velocities are involved.

 

[rgwalt]

But with the moving poll example, both reference frames are completely valid, so which event occurs? There has to be an instant where the front of the garage and the front of the poll are in the same plane.

Ryan

 

[bsobel]

Originally posted by: rgwalt
But with the moving poll example, both reference frames are completely valid, so which event occurs? There has to be an instant where the front of the garage and the front of the poll are in the same plane.

You mixed up some lengths in your post. From my understanding, you'd have two references. From the first (a person outside the garage), you would see a 20 foot pole in a 10 foot garage (10 feet sticking out). From the 'pole rider' view, you would see a 10 foot pole in a 5 foot garage with 5 feet sticking out.

Bill

 

[rgwalt]

No, the lengths are correct. The guy on the garage would see a 10 ft pole in a 10 ft garage, a perfect fit. The pole rider sees a garage coming at him and since both frames are at a constant velocity, both are completely valid frames. The problem is that the pole rider still measures his pole as being 20 ft long, and the garage is compressed to five feet long. So, when the end of the pole is even with the back end of the garage (ie as much of the pole is in the garage as possible) then the two different observes witness two different events. The guy on the garage sees a perfect fit. They guy on the pole thinks that there is 15 ft of pole sticking out of the garage.

Though I would like to claim credit for this problem, I didn't come up with it. It is a classical problem arising from the theory of special relativity. You can read about it here, including the solution to the paradox.

Pole in the barn.

Helio got it right by stating that events don't occur simultaneously in all reference frames. That means that if you are traveling with a high velocity wrt to another reference frame (frame B) and someone in frame B turns on two light bulbs at the same time, you may not necessarily view them as coming on at the same time.

In the barn and pole example, both doors do not shut simultaneously in the pole riders reference frame. As a result, the pole can be completely enclosed by the barn for a single instant from the point of view of the guy on the barn. Now, if the doors don't open and are stress-proof, the pole will stop and expand, shattering the pole.

Ryan

 

[RossGr]

Originally posted by: heliomphalodon
Special Relativity is based upon two postulates: (the following is a direct quote from Einstein)

1) The laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems of coordinates in uniform translatory motion.
2) Any ray of light moves in the "stationary" system of coordinates with determined velocity c, whether the ray be emitted by a stationary or by a moving body.

By "stationary" Einstein means simply "Newtonian" -- not absolute.

Why should we accept Einstein's postulates (and thereby reject your intuition that it is the speed of light that varies, not the time interval)?
Simple -- experimental results support Einstein's position. Time dilation is a measured fact. It's hard to get used to, as are the loss of "simultaneity" of events and contraction of lengths -- but that's only because we don't generally experience these effects in a noticable way.

Since light is postulated to move with velocity c, time intervals are defined in terms of the speed of light -- not the other way around. The evidence in Einstein's favor is very, very strong.

Seems that it all hangs on this question. Where did Einstein get this idea? Is it something that he dreamt up? Well since Michelson and Morely were running experiments to test the consantcy of the speed of light there must have been something driving that experiment. After all these quys were not working in a vacumn and did not simply perform random experiments.

It all started in the 1860s when James Clerk Maxwell derived, from the work of Faraday, Gauss, Coulmb, and Ampere, a set of equations which now bear the name Maxwells Equations, This set of 4
Equations can be cast in the form the wave equation. Maxwell did this and found that these waves, electromagnetic waves, would propagate at a constant velocity given by the expression 1/Sqrt(e0 mu0) where e0 is the permittivity of free space and mu0 is the permeability of free space. Both of these constants had been determined experimentaly long before. When he did this simple calculation he found the number to be equal to the experimentally determined speed of light. This was a surprising result, and was the first true fundamental evidence that light is an electromagnetic phenomena.

About 20 yrs after Maxwell predicted traveling electromagnetic waves Hertz was finally able to generate the waves, working of course from Maxwell's equations.

The predicted constansy of the speed of these waves created quite a stir, because up to that point all velocities were additve. This one appeared to be special, it did not depend on, nor was relative to, any existing motion. Insead it depends only on the fundamental properties of space. This caused a 50yr split between mechanical motion and electromagnetism/light which apparently could not be reconciled. That is until Enistein, he postulated the constancy of the speed of light because that was given by Maxwell's equations and the reasons why it is constant were not the topic of his work. His work was an exploration of the RESULTS of a constant speed of light.

 

[zephyrprime]

Originally posted by: rgwalt
Nice post helio... OK, time to break out something really funky about length contraction. OK, here is the basic idea... objects that are moving at high velocities "shrink" in the direction of motion. For instance, a 20 ft pole appears to be 10 ft long by a non-moving observer when moving at 0.866c (not positive on this number). Seems weird, but
...etc...etc...etc...
Both reference frames are completely valid. What happens? Does the pole fit in the carport for an instant, or does at least 15ft of it stick out? Do two different reference frames observe different events occuring in the same time and place in space? What the dilly-o?

Ryan
--------------------------------------------------------------------------------


I can't really deal with this apparent paradox in full, but I'll venture to say that the confusion arises because of lack of simultaneity. We're used to situations where the front end of the pole reaches the front end of the carport at the same time that the rear end of the pole reaches the rear end of the carport. That's not the case when relativistic velocities are involved.

Your instincts are correct. This problem is resolved by the lack of simultaneity. This is a classic problem and is solved by any student in a special relativity class. For the person by the road, the rod fits in the car port for a instant. For the person on the pole, the exit carport closes for an instant and then opens. The pole then progresses 15ft out the port. Now the entry door closes for and instant and opens.

I have my own explanation for special relativity which I'm too tired to type right now but I'll post again tomorrow.

 

[Peacekeeper100]

Originally posted by: Cuda13337
Wow, very interesting stuff guys. Im just curious, what courses do you take in colllege to learn about this type of stuff? Is it mainly physics and that sort of thing? Its very interesting, and in a year Ill be going to college (finally) So I'd like to know what I should look for to study this more.

My college had it as a third level physics. Just look for a modern physics class.

 

[Peacekeeper100]

One of my physics teachers was saying for the whole time travel thing the space ship would have to go to a planet and return to earth without changing it's velocity. Since this is impossible since the ship would have to slow down and reverse direction, then time travel in the Theory of Relativity would never happen.

Of course you have to remember that it is about relativity.

I got it planted into my head that of course you will travel back in time when going close to the speed of light. Example: If the sun exploded you would see it on earth very soon after it did so. But if right before that your ship left earth at 0.99c and traveled for lets say 20 days and stopped. You would then see the sun explode. This would mean that you would see an event that happened 20 days ago so you traveled back in time. This always made sense to me since it is "relative" to your position. I don't know if that is the whole theory of time travel or not, or if I even have it right, but I otherwise I can't see it. This especially made sense after the whole can't change velocity thing since velocity depends on direction.

 

[Peacekeeper100]

Another thing I would like to say is that all these are theory's. None of them have been proven to the point that they are not called theory's any longer. When I read all these theory's I just thing about what if everyone was missing something. Some phenomenon that no one was discovered yet that puts everything together. I think Maxwell's equations are about the only thing that was actually been proven. Especially in the time travel parts.

Anybody here majored in Solid-State Electronics? I am graduating with a BS in Dec in it, and am starting in the MS program in Dec with the same major. All the theory's they have for that are insane. They see what happens experimentally and then put an equation to it. Most of these people don't really understand it, they just happen to find an equation that fits the results, but if one thing changes the equation goes out the window and no one know why until the next theory is produced. I have a feeling it is the same with all these theory's. No one really understands it, they just find a result, put an equation to it, and then try to explain the equation and result. It sounds right, and can't be proven wrong, so that's how it is explained.

 

[sao123]

Back to the original question...

Mathematically, ND's theory is correct, all you have to do is understand component factoring.

The observer at the absolute point has the correct absolute measurement. The observer onboard the spaceship has only a net measurement.
Simple mechanical physics will solve this problem.

Consider the onboard viewer, the ship and the moving object as a system.
From the absolute posistion observer, use the projectile motion equation (X = Vi*T + 1/2*A*T^2), to find the velocity and acceleration. This vector can be broken down into its sin and cos components. (not going to go through how to do that, too easy, and would take too long.)

now to the onboard observer... only the sin component is observed. However the cos component is acting on the entire system.
When some given event happens to a system, it affects all internal parts of the system totaly & equally, yet this effect is undetectable to an observer within the system. (imagine the mathematic laws of distribution -> a*(b+c) = ab + ac ).
therefore the onboard observer sees a net effect, and not the entire one, even though it is not observed, it still takes place.

If you want another example of a similar concept, research the Earths Coriolis effect. Same concept, just applies to earth.

 

[BumJCRules]

I do not see where the "Earths Coriolis effect" fits into this. Do you mean an observer from space looking at the earth?

How does air that is pushed by the friction with the surface of the Earth work with "percieved" changes in sight or sound? (Both using electromagnetic waves.)

 

[sao123]

Because the Coriolis affect has nothing to do with weather, that is just the primary the place where the theory is observed in practice.

The coriolis effect basically states that due to the rotation of the earth, all motion on earth that is observed is only net displacement. The true displacement can only be seen from an absolute point in space. To an observer on earth an object in motion would appear to move in a striaght line. However to an observer in space, a curved path (and hence a larger displacement) would be the true measurement of the movement. Exact same question that ND had, just in different closed system.

 

[Belegost]

The true displacement can only be seen from an absolute point in space.

You'd have to assume there is some absolute point in space from which to define an absolute displacement.

However, it's just this assumption that relatively negates; if all reference frames are equal, then none of them are absolute, all points are relative, and there can be no definition of "true" displacement. You can only measure displacement, velocity, time, etc. relative to a given reference frame, and there is no absolute frame to compare to.

 

[zephyrprime]

ND, the problem is you are trying to understand time dilation but you do not accept the premises on which the time dilation argument rests. Namely:

1. Things are relative. There are no absolute reference frames. Law of physics same in all inertial reference frames.
2. The speed of light is a basic physical phenomena and is the same for all observers and all reference frames.

You stated that you don't believe either of these premises when you said:
"I think of the universe in terms of quantifiable "points"
That is to say, "I believe that there are absolute reference points."
"the speed of light is the maximum of 1 point per time unit"
That is to say, "I believe the speed of light is not the same for all observers."

So given these two premises, your mathmatatical argument is completely valid. So you see, your "1) understanding of what time dilation is" and your "2) reasoning for the contradiction." are perfectly valid. The reason why your understanding of time dilation is wrong is not becuase of your line of reasoning but because of your basic premises.

I was exposed to the "train and bouncing light" thought experiment and didn't really understand it for the same reason you don't understand time dilation. I've always thought that giving students the "train" scenario was stupid because the real problem students have with relativity is that they don't accept the two basic premises of relativity.

I don't know if anyone has ever figured out a reason why einstein's two special relativity postulates are true. But they are true. Everytime anyone ever uses a GPS he proves that general relativity works. Every GPS unit is programmed with equations derived from general relativity in order to compensate for the fact that sattellites in orbit observe the passage of time a little faster than you and me. Einstein himself first conceived of special relativity when he realized that Newtonian mechanics applied to Maxwell's Laws of electromagnatism yielded contradications. So either Maxwell's Laws were wrong or Newtonian mechanics where wrong. Most the physicists of the day believed that Maxwell's Laws must be wrong so they set about trying to modifiy Maxwell's equations to make them fit Newtonian mechanics. Einstein explored the possiblity the Newton might be wrong.

Anyway, I've developed my own little motivations and theories to explain postulates 1&2. Here they are:

1. First of all, try finding an absolute reference frame. Good luck. The earth is spinning around the sun and the sun is spinning around the center of the milky way. The milky way is locked in a slow dance with andromeda. The local group of galaxies is spinning around the local supercluster and beyond that motions are washed out by the expansion of the universe. And the universe's expansion has no center radiating point!

Here's a thought experiment. Pretend you were god and created your own little universe. The universe you create is infinite. There's also absolutely nothing in this universe. No features whatsoever. This universe could be called perfectly smooth. Now pretend that you placed a subatomic avatar of yourself in your universe you just created. Now here's the big question: How fast is your avatar moving?

Could you avatar move at all? What if you created a boot to give your subatomic particle a kick. Is it moving now?

2. What follows is my own hypothesis and I can't prove it. Reader beware.

I believe that the reason the speed of light is fixed is because the speed of light is time. Stated another way, we move through the dimension of time at the speed of light. This velocity was in some unknown way inbued onto everything in the universe at the moment of creation. This temporal kinetic energy is actually the only kinetic energy anything has. But this temporal kinetic energy has a perculiar property: it can be transformed into spatial kinetic energy. But because of the conservation of energy and momentum, translating temporal velocity into spatial velocity in an object reduces the temporal velocity of an object. This is actually just simple conservation of momemtum and energy (aka monenergy to people that know about S.R.). Now if temporal velocity is reduced and if temporal motion is time, than a reduction in temporal velocity is simply time moving slower. That is, time dilation. The reason why nothing can move faster than the speed of light is because everything only has as much monenergy as was imbued into it at the big bang and if an object's monenergy is completely allocated to spatial velocity then that object is moving at the speed of light. The reason why lack of simultaneuity occurs is because of relativity. All inertial reference frames are equally valid. Including inertial reference frames that include both a spatial and a temporal component. That is to say, all paths through time are valid inertial frames. There's no one direction of space-time vector that is "special" and that can be used to measure all others.

Now an interesting consequences of my crazy hypothesis is that the creation of the universe violates the conservation of momentum. Nothing in our universe seems to have negative temporal velocity to balance out the positive temporal velocity that we all have. So, I thought that one way to resolve this problem is to postulate the existance of a sister universe to our own. In that universe, everything has negative temporal velocity (of course, anyone in this other universe would perceive that it's actually *our* universe that has negative temporal velocity). Also, this universe would also have net spin that is the opposite of that in our universe in order to satisfy conservation of angular momentum.
given the conservation of momentum, it would seem

 

[sao123]

Just to be thorough, i still think it would be mathematically possible to calculate the exact total displcaement by adding up all the universal vectors. Let me see if I can prove it.

At every level, a closed set system could be defined, except at the universal level. Example... the set of all galaxies, a cluster of galaxies, 1 galaxy, a star cluster, a solar system...etcetc clear down to the rocket-observer-projectile closed system.

The universe cannot be considered a closed system, because it is an infinite & expanding. (although how it is both infinite and expanding is another discussion) The all largest closed system would contain every finite existing item in the universe. Leaving the universe to containe 2 sets. The galactic set (which contains all matter), and the null set.
now because the universe contains null space and is infinite and expanding, I can theorize that the universe is not full. (IE: there is still room to put more stuff in it.) Therefore I can hypothesize that there exists an empty point in space that is not in the set of galactic space forces and matter. Because the universe is not a closed system set and is infinite it is not subject to external forces. therefore I can conclude that an unaffected absolute point must exist somewhere in the universe.

 

[heliomphalodon]

Recent observations of the cosmic background radiation indicate that it is not isotropic. In fact, an apparent doppler shift bias is observed. This suggests that a universal preferred reference frame may be definable -- one in which the cosmic background radiation is isotropic and exhibits no doppler shift bias.

 

[fa28]

So what if light isn't a constant , read this: Einstein's relativity theory hits a speed bump