Motion is created by acceleration alone. Acceleration is detactable as a fluctuation of weight. Einstein asked you to forget about how things got to be where they are; that you not include the acceleration that is in the timeline.
If you include the acceleration that created everythings motion then all motions are knowable after the fact.
MItch Raemsch
Motion itself isn't directly detectable either.
We might look at the Moon and say we can see motion, but we aren't actually sensing the motion of the Moon but a force and the associated acceleration of photons reflecting off the surface of the Moon.
Imagine a universe filled with objects moving in precisely the same direction with precisely the same velocity. None of them interact (or accelerate) and none of them would be visible to each other because none of them would change in position relative to the others (shining a light to see them creates photons and accelerations that wouldn't be aligned with this motion and so would violate the idea of everything moving in the same direction). So motion itself isn't directly detectable, but instead changes in motion are detected (sensed, for example, as photons and the changes in motion that the accelerations they generate provide).
It's again though not entirely true to say that we directly detect acceleration as a similar problem would occur within a universe having all objects being accelerated in precisely the same manner, so this would lead to the conclusion that a change in accleration, or 'jerk' would be detected instead, but you can continue on like this and continually say that it must be a higher derivative of motion that's detected, but paradoxically show that in a universe containing only that form of motion it can't be seen as being detectable.
This leads to the conclusion that we detect things in a relative manner and require contrasts to exist in order for something to be detected, but what specific property of motion do we detect? It would appear we need at least 2 types of motion to exist as if everything possessed an identical form of motion then none of that motion is detectable. This begins to imply that motion must be quantized and exist in at least 2 different forms.
This is one reason why motion appears to be required to be quantized as none of these higher and higher derivatives of motion appear to be directly detectable but instead that the progression must be capable of being extended to any limit (a related function is an exponential because all such intermediate derivatives are identical and an exponentially spread position requires an exponentially increasing velocity and acceleration and jerk etc.) Instead, changes could be instantaneous and quantized and not infinitely subdivisible. This allows all forces to be detected as discrete units of acceleration (though I'd say you can also see this in reverse as we detect discrete things and then construct an interpretation of motion and space from them).
I'd have to say that it appears much more likely that motion isn't directly detectable at all because it's not a fundamental physical property of objects but that instead we have exchanges of energy that create the appearance of interactions that appear to have associated correlations seen as motions through space. So the appearance of motion represents an "intellegently" extracted knowledge of predictable characteristics found in detected exchanges of discrete energies. (I won't go so far to say motion is an illusion though but that it represents a knowledge of space and could vary subjectively depending upon who's the one observing motions and what underlying assumptions are made about the properties of those motions - it may be that humans see motions in space in a form that's not the only manner of viewing it but instead derived from our physical forms and instinctive mental processes)
We might look at the Moon and say we can see motion, but we aren't actually sensing the motion of the Moon but a force and the associated acceleration of photons reflecting off the surface of the Moon.
Imagine a universe filled with objects moving in precisely the same direction with precisely the same velocity. None of them interact (or accelerate) and none of them would be visible to each other because none of them would change in position relative to the others (shining a light to see them creates photons and accelerations that wouldn't be aligned with this motion and so would violate the idea of everything moving in the same direction). So motion itself isn't directly detectable, but instead changes in motion are detected (sensed, for example, as photons and the changes in motion that the accelerations they generate provide).
It's again though not entirely true to say that we directly detect acceleration as a similar problem would occur within a universe having all objects being accelerated in precisely the same manner, so this would lead to the conclusion that a change in accleration, or 'jerk' would be detected instead, but you can continue on like this and continually say that it must be a higher derivative of motion that's detected, but paradoxically show that in a universe containing only that form of motion it can't be seen as being detectable.
This leads to the conclusion that we detect things in a relative manner and require contrasts to exist in order for something to be detected, but what specific property of motion do we detect? It would appear we need at least 2 types of motion to exist as if everything possessed an identical form of motion then none of that motion is detectable. This begins to imply that motion must be quantized and exist in at least 2 different forms.
This is one reason why motion appears to be required to be quantized as none of these higher and higher derivatives of motion appear to be directly detectable but instead that the progression must be capable of being extended to any limit (a related function is an exponential because all such intermediate derivatives are identical and an exponentially spread position requires an exponentially increasing velocity and acceleration and jerk etc.) Instead, changes could be instantaneous and quantized and not infinitely subdivisible. This allows all forces to be detected as discrete units of acceleration (though I'd say you can also see this in reverse as we detect discrete things and then construct an interpretation of motion and space from them).
I'd have to say that it appears much more likely that motion isn't directly detectable at all because it's not a fundamental physical property of objects but that instead we have exchanges of energy that create the appearance of interactions that appear to have associated correlations seen as motions through space. So the appearance of motion represents an "intellegently" extracted knowledge of predictable characteristics found in detected exchanges of discrete energies. (I won't go so far to say motion is an illusion though but that it represents a knowledge of space and could vary subjectively depending upon who's the one observing motions and what underlying assumptions are made about the properties of those motions - it may be that humans see motions in space in a form that's not the only manner of viewing it but instead derived from our physical forms and instinctive mental processes)
My point is you can't leave out the acceleration that has happened before that caused the object to move in the first place. The fluctuation of weight caused by the accleration was detectable.
If your clock is runnning slow compared to another it means you are moving faster in SR.
Mitch Raemsch
If your clock is runnning slow compared to another it means you are moving faster in SR.
Mitch Raemsch
QUOTE (Nick+Aug 14 2007, 02:35 AM)
My point is you can't leave out the acceleration that has happened before that caused the object to move in the first place.
Mitch Raemsch
Yes, I agree. I guess we're really saying the same thing. Motion can be seen to arise from other causes (as in your example of time dilation a detected slowing in the exchange of energies within the moving object) and hence doesn't need to be considered a fundamental property of an object, but instead is a resultant secondary attribute generated by less relative, and more indivisible and absolute physical units. (Of course you'd still have to pick something as being a fundamental cause of motion and as I indicated above, I'd pick detectable discrete units of energy as causing those observed changes in motion)
Mitch Raemsch
Yes, I agree. I guess we're really saying the same thing. Motion can be seen to arise from other causes (as in your example of time dilation a detected slowing in the exchange of energies within the moving object) and hence doesn't need to be considered a fundamental property of an object, but instead is a resultant secondary attribute generated by less relative, and more indivisible and absolute physical units. (Of course you'd still have to pick something as being a fundamental cause of motion and as I indicated above, I'd pick detectable discrete units of energy as causing those observed changes in motion)
QUOTE (Nick+Aug 14 2007, 01:56 AM)
Einstein asked you to forget about how things got to be where they are; that you not include the acceleration that is in the timeline.
If you include the acceleration that created everythings motion then all motions are knowable after the fact.
MItch Raemsch
Well, sorry to burst your bubble but how do you explain that all experiments attempting to detect Earth "absolute motion thru aether" have not detected any?
I guess that the Earth may have "forgotten" its primordial acceleration that set it into motion.
If you include the acceleration that created everythings motion then all motions are knowable after the fact.
MItch Raemsch
Well, sorry to burst your bubble but how do you explain that all experiments attempting to detect Earth "absolute motion thru aether" have not detected any?
I guess that the Earth may have "forgotten" its primordial acceleration that set it into motion.
The earths motion through space alone can't be detected. But if it were to spin faster it would be detected.
Mitch Raemsch -- Light Love --
Mitch Raemsch -- Light Love --
QUOTE (Nick+Aug 14 2007, 02:48 AM)
The earths motion through space alone can't be detected.
Correct , but now you are contradicting yourself.
Correct again (surprise, you may evolve from the current crank state). Actually you can even detect uniform angular speed. Do you know how? (hint: there is an experiment that was done at the beginning of the 20-th century)
Correct , but now you are contradicting yourself.
QUOTE
But if it were to spin faster it would be detected.
Correct again (surprise, you may evolve from the current crank state). Actually you can even detect uniform angular speed. Do you know how? (hint: there is an experiment that was done at the beginning of the 20-th century)
QUOTE (Dallas+Aug 14 2007, 02:55 AM)
Correct , but now you are contradicting yourself.
What was the earths original motion if it did not accelerate?
What was the earths original motion if it did not accelerate?
QUOTE (Nick+Aug 14 2007, 02:58 AM)
What was the earths original motion if it did not accelerate?
Now, you were doing so well
Unfortunately it doesn't last long.
QUOTE (Dallas+Aug 14 2007, 03:00 AM)
Now, you were doing so well
Unfortunately it doesn't last long. Please show me where I am wrong about the earths original motion.
Acceleration alone creates it.
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