Gravity why reinvent it?

[jajrussel]

What exactly is wrong with gravity pulling two objects together? Isn't it normal for this pulling action to be from center mass to center mass? Isn't a geodesic nothing more than the path both objects have to take because the physics of motion won't allow any other path?

 

Time is always distorted when two, or more compared velocities differ, isn't it? It seems to me that we tend to measure time in a straight line as per our position, yet rarely are we or what we are measuring moving in a straight line. When the earth spins a person at the equator actually does move further through space than a person in New York. Still take 24 hours. It is perfectly normal. It is not time dilation because we don't view it as such. We are using a straight measure, and not caring about the curve, or difference in distance. Make the earth really, really big and we might reach a point where we actually have to care, but wouldn't that be because we would be so far apart that we would risk going back, or forward in time just going from New York, to Kenya, or from Kenya, to New York?

 

The one thing I really don't understand is why my car would be bigger in one place than in another, unless it has something to do with that fact of how far away I am from the car when I measure it, compared to how how far we have moved when I finish measuring it? A moving car does look smaller when I am some distance from it, as does the distance it seems to be moving, but that is also normal. What would be weird would be if the car looked small, but the distance it is moving looked really big. Actually when I am following a moving car with my eyes it looks smaller than it does when I stop following it, and let it continue on. That last second the image is just distorted enough to make it seem bigger.

 

It just seems to me that dilation, and distortion would only make a difference if you didn't allow for the difference of physical realities. Isn't that what we were doing before Einstein?

 

It seems to me that the only real difference between Newton, and Einstein is that Newton didn't allow that distance might cause a delay. Einstein presented that nothing moves faster than light, not even gravity. Gravity didn't suddenly start behaving any differently with general relativity. He didn't actually reinvent gravity.

 

Two objects in space are attracted to each other. When first viewed they may seem to be moving parallel to each other. If no other force interferes they will eventually get close, might even collide. Plot their different paths, eventually you will notice that their paths are curved. You might predict that if they are the only objects in the area their paths have always been curved, even if initially they seemed to be moving parallel to each other. The moon orbiting earth is nothing more than this taken to complexity. All it takes is gravity, and the physics of motion. Where exactly does warped space need to get involved.

 

It seems to me that time distortion comes about, because we think of time like Newton's view of gravity. There is a problem with the way we think about it. It is assumed that if we are moving really, really fast time will show down maybe even stop, but no matter how fast, or slow we are moving we are going to measure time at the same rate, just like no matter how fast, or slow we are moving we are going to measure c to be the same. I don't see how we could expect c to be invariant without our measure of time also being invariant.

 

The distorted way of viewing time is to think that if we could only live on Neptune, and somehow make Neptune keep pace with earth's orbit we would actually live longer than our twin on earth.

[Ophiolite]

There seems to be quite a lot you don't understand. I trust one or more other members will recommend suitable texts that would help remove that confusion. I do hope, though, that you aren't confusing your lack of understanding with identification of genuine weaknesses in current theory.

[jajrussel]

There seems to be quite a lot you don't understand. I trust one or more other members will recommend suitable texts that would help remove that confusion. I do hope, though, that you aren't confusing your lack of understanding with identification of genuine weaknesses in current theory.

I have books and I like to read, and I am always open to suggestion. I was specific about what I don't understand. Perhaps if you are specific about the lots of other things I don't understand that deal with the topic I might be more inlightened.

 

Isn't the idea of warped space simply a way of visually describing what is happening as the moon orbits earth? Kind Of like the bowling ball on the blanket, except that it sounds way cooler. It's not like I am saying gravity pushes, I am saying gravity pulls, and that things like velocity, and direction have all to do with the effect. The pull is straight, but they can't just stop then go straight, so they do what they can. We generally call it an orbit. There is no either, there is nothing to warp. The only physical force acting on the two is gravity, and it is pulling straight between the center masses, except there is also the sun, and other planets, and I am sure a lot of other things, also pulling straight, and if not for the fact of different masses, and different directions, and the weakness of gravity they might actually just move in a straight line until they slammed into each other. Except for the fact that there is no straight line connection with the type of acceleration necessary to bring them together. Every single one of their paths would have to curve. It is still a pull thing, and has nothing to actually to do with warped space, except as a visualization.

Edited December 18, 2015 by jajrussel

[Bill Angel]

In his 1915 paper, Einstein showed that the effects of gravity could be described, by supposing that space-time was warped or distorted, by the matter and energy in it. We can actually observe this warping of space-time, produced by the mass of the Sun, in the slight bending of light or radio waves, passing close to the Sun. This causes the apparent position of the star or radio source, to shift slightly, when the Sun is between the Earth and the source. The shift is very small, about a thousandth of a degree, equivalent to a movement of an inch, at a distance of a mile. Nevertheless, it can be measured with great accuracy, and it agrees with the predictions of General Relativity. We have experimental evidence, that space and time are warped.

See http://www.hawking.org.uk/space-and-time-warps.html

[geordief]

There was also an anomaly in the measurements of the orbit of the planet Mercury which was not predicted by Newtonian mechanics.

 

Einstein's Relativity Theory was able to predict it accurately.

 

http://physics.ucr.edu/~wudka/Physics7/Notes_www/node98.html

[MigL]

Over the centuries people have noticed that masses follow certain trajectories when acted on by other masses.

Newton was kind enough to put these actions in a general form which is still quite accurate today, but there were some anomalies.

Einstein realised that if we describe space-time by a generalised co-ordinate system, we can account for these trajectories by considering this co-ordinate system to be 'warped' or 'curved' by stress-energy.

This theory of gravity has been so successful because it correctly accounts for the trajectory of Mercury about the Sun, or even that of light around massively gravitating objects.

 

Again, it is the 'model', GR, which 'warps' or 'curves'. Whether or not space-time is ACTUALLY 'warped' or 'curved' is anybody's guess.

But the theory does a damn good job of 'modelling' reality.

( at least far enough away from inflection points such as singularities, and the quantum realm )

[jajrussel]

See http://www.hawking.org.uk/space-and-time-warps.html

Thanks for the Web direct, I will eventually read it when the place where I work allows me some me time.

 

But, doesn't this assume that a photons path is always straight,while disallowing that a photons relative mass might act like any other mass particle gravitationally. I know the assertion that a photons velocity is always c, but does it have to move through warped space in order to maintain the assertion?

[studiot]

 

But, doesn't this assume that a photons path is always straight,

 

The problem of defining what is meant by 'straight' is not as easy or straightforward { } as you might think.

 

Newton, of course, didn't actually say straight. His words were

 

"In its right line"

 

Edited December 19, 2015 by studiot

[Strange]

What exactly is wrong with gravity pulling two objects together? Isn't it normal for this pulling action to be from center mass to center mass?

 

I assume your question is "Why reinvent Newtonian gravity?" In other words, why do we need relativity to describe gravity?

 

If so, there are a number of problems with Newtonian gravity some of which Newton knew about and some which were discovered later. For example, Newton's "force" has to act instantaneously over any distance. He knew that was implausible. Since then more accurate astronomy found things like the precession of Mercury that couldn't be explained by Newtonian gravity.

 

 

When the earth spins a person at the equator actually does move further through space than a person in New York. Still take 24 hours. It is perfectly normal. It is not time dilation because we don't view it as such.

 

This is, as you say, not time dilation. It is just a difference in speed.

 

However, time dilation is a real thing even if we are not normally aware of it. But we now have clocks accurate enough that we have to take time dilation into account between moving objects (e.g. satellites orbiting the Earth, particles going round the LHC).

 

Also, a clock at the top of a mountain will tick slightly faster than one at the bottom because of gravitational time dilation. In fact, we can measure this difference over very small distances: between one step and the next on your staircase.

 

 

It seems to me that the only real difference between Newton, and Einstein is that Newton didn't allow that distance might cause a delay.

 

That is a key point. Newtonian gravity doesn't allow for a delay. Einstein then suggested that the light speed delay is the same for all observers. From this, it is straightforward to show that time and length must change depending on the observer.

 

 

Isn't the idea of warped space simply a way of visually describing what is happening as the moon orbits earth?

 

While that path is caused by the curvature of space-time, what you are seeing in that (nearly) circular orbit is not that curvature. For example, if something falls to Earth in a straight line, that is also due to the curvature of space-time, but you perceive it as the effects of a force, rather than a curved path.

[geordief]

I understand that we can appreciate(and measure) the curvedness of space-time by finding a group of 3 objects in space (stars ,perhaps or galaxies) and measuring their light distance from each other and noting that the triangle formed does not have angles that add up to 180 degrees .

 

If I am right here ,can I ask if this triangle can be said to represent** a "surface in space time" ?

 

If so what kind ? Are there different categories of such surfaces depending on whether (in the model) space is held constant or time is held constant?

 

If I am not right, where am I going wrong for the most part -or at the outset?

 

 

"enclose " rather than "represent" I think I should have written.

Edited December 19, 2015 by geordief

[jajrussel]

 

The problem of defining what is meant by 'straight' is not as easy or straightforward { } as you might think.

 

Newton, of course, didn't actually say straight. His words were

 

"In its right line"

 

Perhaps an old fashioned way of saying geodesic?

 

I tried to post the following as a separate post, but it would not allow me to, so the following contains thoughts that pertain to other post in the thread.

I kind of got lazy, and didn't want to quote a long post then figure it how to compose the thing. Sorry.

 

It seems to me that when people start using geodesics as the reason something is following a certain path it alludes that no force is evolved. Then people start trying to get creative. The allusion is that it isn't gravity, so then what is actually happening if there is no pull. I read one assertion that it wasn't pull it was all push? Then there is the everything is flowing toward another dimension? Saying that space is warped when no one can define what is warped except to say it is space, and it's warped doesn't seem to help. There have been test done it isn't eather,or is it aether,I can never remember the spelling, and my spell checker tends to dumb up on this word, but it doesn't matter because it is disallowed. Gravity waves seems interesting, especially if the intersecting waves are said to be a form of energy field that can change density due to the intersecting waves that would force something to follow a geodesic, but then that wouldn't be space, but something that occupies space, still makes more sense than space that can't be defined warping, but still maybe just a little to creative. Maybe.

 

Time dilation is real enough that different observers can get different results of the same event, but we tend to take it to dramatic possibilities. I do love a good Syfy book, well actually I tend to love the bad Syfy books also, but except for being aware of the possibilities what it actually does is explain why different observers get different results.

Edited December 19, 2015 by jajrussel

[Strange]

It seems to me that when people start using geodesics as the reason something is following a certain path it alludes that no force is evolved.

 

Things follow geodesics (the generalization of straight lines) in the absence of any force because that is the minimum energy path.

 

Then people start trying to get creative. The allusion is that it isn't gravity, so then what is actually happening if there is no pull. I read one assertion that it wasn't pull it was all push? Then there is the everything is flowing toward another dimension?

I don't know where all that comes from, but it isn't anything to do with GR. And doesn't even seem to have much to do with science.

 

Saying that space is warped when no one can define what is warped except to say it is space, and it's warped doesn't seem to help.

 

This is very precisely defined. It is the geometric relationship between events in space-time (note: not just space) that is curved. Unfortunately the definition requires some pretty advanced maths.

 

Gravity waves seems interesting, especially if the intersecting waves are said to be a form of energy field that can change density due to the intersecting waves that would force something to follow a geodesic, but then that wouldn't be space, but something that occupies space, still makes more sense than space that can't be defined warping, but still maybe just a little to creative. Maybe.

 

Gravitational waves are the dynamically changing curvature of space-time. They are not an "energy field" and they don't force things to follow geodesics.

 

Time dilation is real enough that different observers can get different results of the same event, but we tend to take it to dramatic possibilities. I do love a good Syfy book, well actually I tend to love the bad Syfy books also, but except for being aware of the possibilities what it actually does is explain why different observers get different results.

 

I don't know what you mean by "dramatic possibilities" of "syfy" (sci-fi) but time dilation is a real effect that is used in technology and engineering.

[jajrussel]

Time is always local for the observer. This allows us to derive just how far away something is, such as a nearby star. Dilation occurs to a degree within the local frame. Distance in this case doesn't mean global. As the observer time is local. It doesn't matter what our velocity is. Our calculations do not change, the math stays the same. The degree of dilation stays the same. C is invariant because time is always local to the observer. Two or more different observers, observing under different circumstances make time dilation apparent. The appearance varys. All to limited degrees. This limit is set by the condition of the observer, because for the observer time is local. Conditions set that because of time dilation different observers should have different results, but always to within a local degree. This is because what we can observe is limited. This means that anything beyond what we can observe is speculation. Math suggest possibilities, not probabilities when we try to explore beyond what is possible. C invariant sets all observations local. Locally time dilation stays within the limits of observation.

Edited December 20, 2015 by jajrussel

[studiot]

Time is always local for the observer. This allows us to derive just how far away something is, such as a nearby star. Dilation occurs to a degree within the local frame. Distance in this case doesn't mean global. As the observer time is local. It doesn't matter what our velocity is. Our calculations do not change, the math stays the same. The degree of dilation stays the same. C is invariant because time is always local to the observer. Two or more different observers, observing under different circumstances make time dilation apparent. The appearance varys. All to limited degrees. This limit is set by the condition of the observer, because for the observer time is local. Conditions set that because of time dilation different observers should have different results, but always to within a local degree. This is because what we can observe is limited. This means that anything beyond what we can observe is speculation. Math suggest possibilities, not probabilities when we try to explore beyond what is possible. C invariant sets all observations local. Locally time dilation stays within the limits of observation.

 

 

Have we changed the subject?

 

This bout of thinking by you is not perfect but it is much better than some (ofyour) other stuff so keep on questioning.

 

Edited December 20, 2015 by studiot

[Strange]

Time is always local for the observer. This allows us to derive just how far away something is, such as a nearby star.

 

How does that work?

 

Dilation occurs to a degree within the local frame.

 

No it doesn't, by definition.

 

Distance in this case doesn't mean global. As the observer time is local. It doesn't matter what our velocity is.

 

You seem to think time dilation is due to distance rather then relative velocity. This is incorrect.

 

What does any of this have to do with the subject of gravity?

[jajrussel]

 

 

Have we changed the subject?

 

This bout of thinking by you is not perfect but it is much better than some (ofyour) other stuff so keep on questioning.

 

I'm getting better? I do tend to worry about that kind of thing. I also worry about people getting an unchangeable impression due to my other stuff.

 

My impression based on some of what I have read is that it is thought that there is a relationship between time and gravity. In a black hole time stops? So, I mentioned both in the original post. It is also said that gravity is acceleration. I didn't see a problem talking about both.

 

Now I kind of have to in order to reply to Strange, but Strange is showing signs of wanting to get back to gravity, so I will answer Strange then move back to gravity.

 

I am glad my thinking is getting better. I hate to disappoint, but I probably will. Anyway, thanks for the

[studiot]

I also think Strange was misunderstanding your thinking, perhaps because you are unsure of some of the technical words / technicalities.

 

I am still pondering how to point it in the right direction, because there is something in your local v global idea, but it needs some revision / amplification.

Edited December 20, 2015 by studiot

[Strange]

I agree that some of jajrussel's ideas are correct; for example (proper) time is always local for an observer. And the invariant speed of light is always a local measurement as well. But there also seems to be some confusion, but it isn't clear what it is...

[studiot]

I think what jajrussel means by local is the horizon of influince of a phsyical phenomenon.

 

I can't seem to upload this animated gif from Caltech, but it shows how relativity affects the field of a charge when it moves.

 

Local would mean in the expanding circle.

 

http://www.tapir.caltech.edu/~teviet/Waves/empulse.html

[jajrussel]

 

How does that work?

 

 

No it doesn't, by definition.

 

 

You seem to think time dilation is due to distance rather then relative velocity. This is incorrect.

 

What does any of this have to do with the subject of gravity?

 

 

 

I have a habit of making assumptions, but haven't we created a correlation between seconds and meters with c?

[Strange]

I have a habit of making assumptions, but haven't we created a correlation between seconds and meters with c?

 

Not directly. Relative motion causes a decrease in length and slowing in time. You can think of this as a rotation where some of that length gets converted to time.

[jajrussel]

 

Not directly. Relative motion causes a decrease in length and slowing in time. You can think of this as a rotation where some of that length gets converted to time.

 

I have been trying to visualize this. Maybe I am doing it wrong. I drew a square. Labeled each corner counter clockwise A,B,C,D. Then overlay this square on an x,y axis so that B an D are on the x axis. A,B, and C are observers D is a light that flashes.

 

The light flashes. A and C record a simultaneous event. B does not than. B is more distant from D. This does not seem to be time dilation.

 

Now we do it again, accepting that time is invariant for each position the light flashes in one second intervals.

B moves toward D. At some point all record a simultaneous flash/event. I do not expect D to have reached the y axis when this happens, but I do expect the distance from B to D to be the same as the distance A is from D, and C is from D when they record the simultaneous event. This does not seem to be time dilation.

 

This is obviously a poor visualization. The truth is every time I make an adjustment in who is moving and who is not moving, or allow that everyone is moving. The only difference I can visualize between event recordings is the actual distance of the observer to the flashing light. I can do away with the box and nothing seems to change. The only thing that I do notice is that if I assume position A the other distant points don't seem to be moving around nearly as much as I am when I am moving, and when I am standing still the more distant points seem to be moving more slowly, and not nearly as far as the points closer to me, but this can not be time dilation, because they are distant, and everything about them should appear smaller to me.

 

Apparently for the moment I can not think of a physical way to visualize time dilation. So for now I will sit this aside, and read some more.

[studiot]

 

jajrussel

The truth is every time I make an adjustment in who is moving and who is not moving, or allow that everyone is moving.

 

Everyone is stationary relative to themselves or in their own frame.

It is possible for two 'someones' to be in the same frame, for example a railway train standing at a station and the track & station are in the same frame.

 

In order to observe someone moving the observer has to be in a different frame.

So the observer on the parked in his car by the station paltform sees himself stationary and the train moving (when it moves off)

 

But also an observer who sees both someones moving is in yet another frame.

So the observer standing on the station platform sees both the moving train and the car when it moves as moving.

 

 

 

 

 

By the way did you revisit this thread of yours lately?

 

http://www.scienceforums.net/topic/92850-accuracy-of-a-statement/

[jajrussel]

Everyone is stationary relative to themselves or in their own frame.

It is possible for two 'someones' to be in the same frame, for example a railway train standing at a station and the track & station are in the same frame.

 

In order to observe someone moving the observer has to be in a different frame.

So the observer on the parked in his car by the station paltform sees himself stationary and the train moving (when it moves off)

 

But also an observer who sees both someones moving is in yet another frame.

So the observer standing on the station platform sees both the moving train and the car when it moves as moving.

 

 

 

 

 

By the way did you revisit this thread of yours lately?

 

http://www.scienceforums.net/topic/92850-accuracy-of-a-statement/

Yes, thank you.

 

People often talk of space and time, or spacetime as if it is energy, or has energy. They will say something like, (if time didn't exist then this wouldn't happen, or that couldn't happen).

 

Time is not a energy, or a force. It causes no effects.

 

Space is not a energy, or a force. It causes no effects.

 

Put the two together. Where does this force that warps come from? Where, and from what is the interaction?

 

I am not an expert on special relativety, but it seems to explain why different observers record deferent time results for occurring events. If Linda appears to me to be standing still, when she is actually moving at three miles per hour. Special relativity may supply a reason for my observation, but it doesn't change the event in any way, nor does it change the value of our different observations. If I say hi, and toss her an apple, I don't have to allow for anything. I'm going to toss the apple straight to her, and she will see the apple coming straight to her, and catch it.

(My thinking here came from a video I watched involving a fence,moving walkways, and relativity). Maybe I missed something and need to watch it again, because from my way of thinking our interaction is not affected by either of our observations.

 

The light clock on a moving train explanation? I think it was 6.67ns for a complete cycle between mirrors set a metre apart. One observer sees the photon as having to move further between cycles. When I picture this, and I have seen a similar video except they used space ships. It all seemed to make sense until I thought about the trains momentum, and its effect on the photon, like me sitting on the train along side the clock tossing an apple in the air and catching it. I don't have to toss the apple forward in order to catch it. Straight up works. It might get a little tricky tossing the apple to the other observer, because from my point of view he's the one moving. What I am getting at is that the actual event isn't changing. A complete cycle is still two metres. Now, if I actually had to toss the apple forward in order to catch it, I would be wondering why is my clock working, because I should run out of mirror if I have to toss the apple forward in order to catch it.

 

There is a lot of pretend that goes on sometimes in these explanations, and what if situations. The observer watches a photon bounce at an angle, or what if we are traveling at c, or near c? Pretending makes for a good story, but it doesn't always make for a truth. Could be I am just being hard headed. I've read that time stands still at c. It gets confusing because I've also read that if I am moving at c, well my clock just keeps on ticking normally, and if I could travel at c, well I am going for the clock just keeps on ticking normally, because the alternative doesn't seem to offer much of a future. I am a strong believer in mechanics, but also believe that relativity has its place. Can the photon in the light clock move two metres in a complete cycle, while at the same time move more than two metres in a complete cycle? Well yeah, I don't have to be with the other observer to believe that observation of more than two metres. The question is which observation is more relavent to me.

 

Does this mean space/time is warped? Well, we have two different pretend observations, which are meant to explain relativity, and yes when you think it through it kind of makes sense, and maybe this is just an example of time dilation, but no it isn't. It actually is an example of time dilation, and I am willing to go with distance dilation, but not space, because the only thing said to have changed is the time between cycles, and how far the photon has moved which is a distance measurement, both differences are determined only by the photon.

[Janus]

Yes, thank you.

 

People often talk of space and time, or spacetime as if it is energy, or has energy. They will say something like, (if time didn't exist then this wouldn't happen, or that couldn't happen).

 

Time is not a energy, or a force. It causes no effects.

 

Space is not a energy, or a force. It causes no effects.

 

Put the two together. Where does this force that warps come from? Where, and from what is the interaction?

 

I am not an expert on special relativety, but it seems to explain why different observers record deferent time results for occurring events. If Linda appears to me to be standing still, when she is actually moving at three miles per hour. Special relativity may supply a reason for my observation, but it doesn't change the event in any way, nor does it change the value of our different observations. If I say hi, and toss her an apple, I don't have to allow for anything. I'm going to toss the apple straight to her, and she will see the apple coming straight to her, and catch it.

(My thinking here came from a video I watched involving a fence,moving walkways, and relativity). Maybe I missed something and need to watch it again, because from my way of thinking our interaction is not affected by either of our observations.

 

The light clock on a moving train explanation? I think it was 6.67ns for a complete cycle between mirrors set a metre apart. One observer sees the photon as having to move further between cycles. When I picture this, and I have seen a similar video except they used space ships. It all seemed to make sense until I thought about the trains momentum, and its effect on the photon, like me sitting on the train along side the clock tossing an apple in the air and catching it. I don't have to toss the apple forward in order to catch it. Straight up works. It might get a little tricky tossing the apple to the other observer, because from my point of view he's the one moving. What I am getting at is that the actual event isn't changing. A complete cycle is still two metres. Now, if I actually had to toss the apple forward in order to catch it, I would be wondering why is my clock working, because I should run out of mirror if I have to toss the apple forward in order to catch it.

Let's consider the apple first. You, in train, toss it up, it rises and falls straight back down into your hand, from your perspective. Let's say you toss the ball up one meter, so it will be in the air for 0.9 sec.

Now consider what someone standing by the tracks sees if the train is moving at 1 meter per sec relative to him. He sees the ball leave your hand and return to your hand, just like you do, but in the time between the ball leaving your hand and returning, the train(and your hand has moved 0.9 meters. So relative to him, the ball travels an arc with the take off and landing points 0.9m apart. He can explain this by noting that the train imparts a sideways velocity component to the ball when it leaves your hand.

If we replace the ball with a light bouncing between two mirrors, nothing really changes for you. The light goes straight across and returns in 6.67ns, regardless of how fast you are moving with respect to the tracks.

But for someone standing along the tracks, things appear slightly differently than they did for the ball. He still agrees that the light leaves you, hits the mirror and returns. He also notes that the train, mirror and you move between the time the light leaves you and returns to you, so relative to him, the light takes a "saw tooth" path with each leg of the path longer than the 1 meter separating you from the mirror. But unlike the ball, where he can add a sideways component to the speed the balls travels with respect to himself to make up for the extra distance, the speed of light is invariant, meaning he must measure its speed relative to him as you measure it relative to yourself.

Thus, for him, the light must take longer than 6.67ns to make the round trip between you and mirror. IOW, he measures a longer period of time as passing between these two events than you do.

Okay, but how do we square this with the results of the ball? For instance, if you were to use your light clock to time the toss of the ball, you would measure that it tick 134932533.7 times while the ball was in the air.

The observer by the tracks notes the same number of ticks of your clock while the ball is in the air. But as we noted he will measure your light clock ticks as being longer than you do, so he will also measure the time the ball is in the air as being longer than you do. If the speed of the train is 1m/s like above, this difference is going to be so small that it would be impossible to measure in practice, but if we bump the speed up to 0.6 c than it will be 25% longer for the track observer than it is for the train observer.

Put another way, assuming the track observer has his own light clock with mirrors 1m apart, he will measure his clock ticking once every 6.67ns while measuring yours as ticking once every 8.3375ns(even though you still measure your clock ticking once every 6.67ns).

Now it also important to note what is happening to his clock as measured by you,the train observer. According to you, he is moving with respect the train. Thus it is the light from his light clock that follows the saw tooth path and takes longer to make the round trip. IOW, you will measure his clock and ticking slower than his.(and if he was tossing ball up in the air, it would take longer to return to his hand than yours does. This is what time dilation means; Observers moving relatively with respect to each other measure time intervals differently.

There is a lot of pretend that goes on sometimes in these explanations, and what if situations. The observer watches a photon bounce at an angle, or what if we are traveling at c, or near c? Pretending makes for a good story, but it doesn't always make for a truth. Could be I am just being hard headed. I've read that time stands still at c. It gets confusing because I've also read that if I am moving at c, well my clock just keeps on ticking normally, and if I could travel at c, well I am going for the clock just keeps on ticking normally, because the alternative doesn't seem to offer much of a future. I am a strong believer in mechanics, but also believe that relativity has its place.

Again, time dilation is what happens when two clocks in motion with respect to each other compare their rates. When we say that a clock runs slow as it nears c, we as measured by the observer that he is moving near c relative to. Since any observer's own clock is going to be at rest with respect to him, it will be ticking normally for him

Can the photon in the light clock move two metres in a complete cycle, while at the same time move more than two metres in a complete cycle? Well yeah, I don't have to be with the other observer to believe that observation of more than two metres. The question is which observation is more relavent to me.

It depends on what you mean by "relevant" If you fly off in a rocket at 0.6c for 10 yrs by your clock and return to the Earth and find that 12.5 years have passed on Earth, is that relevant to you?(In case you're wondering how this could be the case, when above I said that you should measure the Earth clock as moving slow due to time dilation, It is due to the fact that there is more going on than just time dilation with this trip)

Does this mean space/time is warped? Well, we have two different pretend observations, which are meant to explain relativity, and yes when you think it through it kind of makes sense, and maybe this is just an example of time dilation, but no it isn't. It actually is an example of time dilation, and I am willing to go with distance dilation, but not space, because the only thing said to have changed is the time between cycles, and how far the photon has moved which is a distance measurement, both differences are determined only by the photon.

There is no space-time warping going on within SR. Space-time curvature is the in the realm of GR. Going back to your comments at the top of your post, Space-time is not considered an energy or force or anything substantial like that. It is in a sense, the "framework" by which we make measurements by. It consists of 3 spacial dimension and one temporal dimension think of three axes crossing marking out the spacial dimensions and forth Time dimension at a right angle to all of these (sometimes it is easier to eliminate one of the spacial dimensions and replace it with the time dimension to make visualization easier). Now here's the trick to space-time vs the notion of "Space and time" that existed before Relativity. With the space and time model, the axes were "fixed" everyone agreed as to the orientation of the Axes. Put another way, there was one unique "direction" to time. With space-time the spacial and temporal dimensions have no unique directions. They remain at right angles to each other, but the "direction" they point can be different depending on who's doing the measurement. So let's say that we have two events separated in space-time. If we ask one observer to measure how far apart these two events are in time and space, he might say that they took x meters from each other and y min apart. Another observer, in motion with respect to the first, will get a different answer.( an analogy would be two people standing on the same spot but facing in different directions, if you ask them how far in front and to the side the same object is from them they will give different answers. Their left/right and front/back are in different directions.

It is also important not to impart to much importance to the photon or light itself. What is important is this relationship between time and space in space-time and that the nature of space-time leads to the existence of an invariant speed ©. Light, having no rest mass is constrained to travel at this speed in a vacuum, so this makes it convenient to use in examples dealing with Relativity. IOW, Relativity determines how light behaves, light does not determine Relativity.