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This is an older essay of mine which suffers greatly from rationalism stemming from my trying to re-think through concepts such as "time" and "motion" and "energy" and "Relativity" without starting from observations. Some of it is OK, but it is very mixed.
Date: Wed, 18 Feb 1998
Motion, Time, and Energy
Thomas M. Miovas, Jr.
Motion is given to us on the perceptual level, and is therefore defined ostensibly (by pointing to moving objects). The concept "motion" is created by observing things moving, choosing the motion of one of them as the standard, and realizing the other motions observed vary only by measurement -- they either move more than the standard or less than the standard. Since the motion of something must be abstracted from that something (motion does not exist apart from something that is moving), a working definition can be given as "a change of position (of something or a part of something)."
But notice that "moving more or less than the standard motion" can be understood in two different ways: 1) the moving object can travel a further or lesser *distance* than the standard; or 2) the moving object can *traverse a given distance* more quickly or more slowly than the standard motion. These two observations imply that "motion" can only be grasped after "distance" has been grasped.
It is by focusing in on the second type of observation that one arrives at the concept "Time." Time is a measure of motion, and is therefore a subset of "motion" (at least at the beginning). To arrive at the concept "motion," one not only needs a standard motion, but also a standard distance over which the motion takes place. The sun rising and setting can be used as a standard for time, because it travels from one horizon to the other (as observed by us); or the shadow of a sundial is observed moving from one side of the apparatus to the other as the sun changes position.
More elaborate measures of motion can be obtained by using a pendulum (where the length of the pendulum arm is crucial), or a watch (with hands) where the distance between the markings is crucial. By making the pendulum arm a set length, or by making the markings (and the inner workings) of a watch consistent, periodic (or repetitive) motion is obtained, making it possible to measure smaller and smaller units of time.
Motion (or change of position) is not the only type of change, however. When we observe wood burning, for instance, we notice a change even though the wood and/or ash remain in the same place. We also notice that some wood burns to ash more quickly or more slowly than other types of wood. So the concept "time" can be expanded to include these other types of changes, by relating the burning wood to the standard periodic motion (which implicitly relates the burning of wood to distance).
The concept "motion" cannot be so expanded, so another concept is needed, namely the concept "energy." In my understanding of "energy," it is a measure of *any sort of physical change* -- from change of position (kinetic energy) to sub-atomic reactions (atomic or nuclear energy).
Regarding Relativity, what Einstein did, essentially, was to show that the concept of "time" is inextricably linked to the concept of "distance." If one is observing a simply clock, such as a ball bouncing up and down in a tube (like an "I"), the distance traversed by the ball is a constant -- *if one is not moving relative to the clock.*
If one is moving relative to the clock, however, the distance the ball traverses (as observed by you) actually *increases*, since it follows a motion more like this: /\. If the standard *distance* traveled by the ball (as observed by you) increases, then your clocks are no longer synchronized (providing the bouncing of the ball does not correspondingly increase), and one has to compensate for the relative motion if one is going to compare events happening here versus over there moving at high speeds relative to you.
There is nothing "spooky" or "anti-law-of-identity" occurring with this observation, though I'm sure this will be a controversial position on this forum. Though I disagree with some of the terminology of Relativity (like "space bending"), I think Einstein hit upon an important fact of existence. I won't go into more detail in this post, but I've noticed the topic has come up, and I will discuss it more later.
In short, there is no "universal time." There are specific clocks, and relative motion of one clock to another must be taken into account, if one is to be accurate.
For a better presentation of these ideas, I would recommend reading my much later essay: Space and Time.