*Einstein's "On the Electrodynamics of Moving Bodies" *sans observateur
Key word-concepts in Einstein's 1905 paper "On the Electrodynamics of Moving Bodies", generally quoted as representing ideas about the theory of special relativity. The point to note is the number of times statements refer to the imaginary "observer", yet are not specified. These statements make the difference between proposing imaginary changes in the objects perceived [viewed, measured] and actual changes in the matter-energy objects themselves.
As an exercise in spacetime/motion reasoning, remove the "observer' from Einstein's statements as given below. I have selected a few statements for illustration:
-We might, of course, content ourselves with **time ***values determined by an observer stationed together* with the watch at the origin of the co-ordinates…,
- …it is possible for an *observer* at B to determine the time values…
-…but that two events which, *viewed* *[by observers]* from a system of co-ordinates, are simultaneous, can no longer be *looked upon* *[by observers]*as simultaneous events when *envisaged** [by observer]*from a system which is in motion relatively to that system.
-We now imagine space *to be measured** [by observer] *from the stationary system K…
-…it being borne in mind that light is always propagated along these axes, when *viewed** [by observer]*from the stationary system…
-But the ray moves relatively to the initial point of k, when* ***measured** [by observer]in the stationary system…
-We now have to prove that any ray of light, *measured** [by observer]* in the moving system, is propagated with the velocity c…
-The wave under consideration is therefore no less a spherical wave with velocity of propagation c when* ***viewed **[by observer*]* in the moving system.
-We call the co-ordinates, *measured** [by observer] *in the system…
-From reasons of symmetry it is now evident that the length of a given rod moving perpendicularly to its axis *measured** [by observer] *in the stationary system…
-The length of the moving rod *measured** [by observer]* in the stationary system does not change,…
-A rigid body which,** ***measured** [by observer]* in a state of rest, has the form of a sphere, therefore has in a state of motion --*-***viewed** [by observer] from the stationary system--- the form of an ellipsoid of revolution with the axis.
-It is clear that the same results hold good of the bodies at rest in the "stationary" system *viewed** [by observer] *from a system of uniform motion.
-What is the rate of this clock, when* ***viewed** [by observer]from the stationary system?
-Therefore…, whence it follows that the time marked by the clock *viewed** [by observer]* in the stationary system is slow by…seconds per second…
-If at the points A and B of K there are stationary clocks which, *viewed** [by observer]*in the stationary system are synchronous…
-By the principle of relativity this electric charge is also of the magnitude "one" when *measured **[by observer]* in the moving system.
-If the quantity of electricity is at rest relatively to the moving system…then the force acting upon it, *measured** [by observer] *in the moving system, is equal to the vector…
-We wish to know the constitution of these waves, when they are *examined by an observer* at rest in the moving system k.
- From the equation for…it follows that if an *observer *is moving with velocity v relatively to an infinitely distant source of light frequency…, in such a way that the connecting line "*source-observer*" makes the angle…with the velocity of the *observer* referred to a system of co-ordinates which is at rest relatively to the source of light, the frequency …of the light *perceived by the observer* is given in the equation…*[Note: one of the few statements by Einstein that explicitly recognizes the significance of the observer.]*
-We still have to find the amplitude of the waves…accordingly as it is *measured **[by observer]* in the stationary system or [*as it is ***measured** by observer] in the moving system,…
-We inquire as to the quantity of energy enclosed by this surface, *viewed** [by observer]* in system k…
-The spherical surface ---*viewed** [by observer]* in the moving system--- is an ellipsoidal surface
-Thus, if we call the light energy enclosed by this surface E when it is *measured** [by observer]* in the stationary system, and …when *measured **[by observer]* in the moving system, we obtain…
-It is remarkable that the energy and the frequency of a light complex vary with the *state of motion of the observer* in accordance with the same law.
-…as follows from the theorem of addition of velocities…the vector…is nothing else than the velocity of the electric charge, *measured** [by observer]* in the system k, we have the proof that, on the basis of our kinematics principles, the electrodynamic foundation of Lorentz's theory of the electrodynamics of moving bodies is in agreement with the principle of relativity.
-If an electrically charged body is in motion anywhere in space without altering its charge when *regarded **[by observer]*from a system of co-ordinates moving with the body, its charge also remains ---*when regarded** [by observer]* from the "stationary" system K ---constant.
-From the above assumption, in combination with the principle of relativity, it is clear that the immediately ensuing time …the electron, *viewed** [by observer]* from the system k, moves in accordance with the equation…
-…are the components of the pondermotive force acting upon the electron, and are so indeed as *viewed** [by observer]* in a system moving at the moment of the electron, with the same velocity as the electron.
-…and if we also decide that the accelerations are to be* ***measured** [by observer] in the stationary system K, we derive from the above equations…
**Your Money and the Physics of Special Relativity**
Let's take a quick look at the math behind the formulas in relation to* mass increase *and *length contraction.*
The best way to offer examples of the mathematical procedures enshrouded in the special relativistic category is through the use of money. We all know how to add, subtract and divide up money.
We can also use some examples relating to automobiles and their speeds which are directly related to the relativistic categories of mass and velocity, respectively.
*Fastest stock automobile on Earth: 434.5 km/hr = 270 mph*
*0-98 mph in 1.67 seconds*
First, let's look at the mathematical procedures using money, and then look at the mass|velocity categories using cars and their speeds.
The use of examples with money is valid for comparison to the theory of special relativity because the mathematical procedures may apply to any matter-energy in spacetime/motion. What applies mathematically to one matter-energy event applies mathematically to all other spacetime/motion events. Consider the squaring of c, the limit of the speed of light. I have $500 dollars. I can square the 500 and obtain 250,000. But, I still have $500.
The use of automobiles is valid for the theory of special relativity, because the physicists state that relativity occurs at every level of spacetime/motion, only we don't notice, or can't observe the differences in length contraction. What applies theoretically to spaceships near the speed of light applies theoretically to automobiles and their corresponding speeds.
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