THE ESSENCE OF SPECIAL RELATIVITY

A light source emits six pulses each second - the distance between the pulses is, accordingly, D = 50000 km. For a stationary (with respect to the source) observer the frequency and the speed of the pulses a

f = 6 ; c = 6D

Then the observer starts moving at (1/2)c = 3D away from the source. According to special relativity, the frequency and the speed of the pulses relative to the moving observer change as follows:

f' = 6 - 3 = 3 ; c' = 6D - 3D = (6 - 3)D = 6D

The calculation:

6 - 3 = 6

that Einsteinians apply to the speed of light but to nothing else in Divine Albert's world is the essence of special relativity:

http://img15.hostingpics.net/pics/86...uletableau.jpg

This calculation, 6-3=6, so popular in Divine Albert's world, is equivalent to the calculation 2+2=5 popular in Big Brother's world:

http://ebooks.adelaide.edu.au/o/orwe...hapter1.7.html
"In the end the Party would announce that two and two made five, and you would have to believe it. It was inevitable that they should make that claim sooner or later: the logic of their position demanded it. Not merely the validity of experience, but the very existence of external reality, was tacitly denied by their philosophy. The heresy of heresies was common sense. And what was terrifying was not that they would kill you for thinking otherwise, but that they might be right. For, after all, how do we know that two and two make four? Or that the force of gravity works? Or that the past is unchangeable? If both the past and the external world exist only in the mind, and if the mind itself is controllable what then?"

Pentcho Valev

http://www.aip.org/history/einstein/...relativity.htm
John Stachel: "But here he ran into the most blatant-seeming contradiction, which I mentioned earlier when first discussing the two principles. As noted then, the Maxwell-Lorentz equations imply that there exists (at least) one inertial frame in which the speed of light is a constant regardless of the motion of the light source. Einstein's version of the relativity principle (minus the ether) requires that, if this is true for one inertial frame, it must be true for all inertial frames. But this seems to be nonsense. How can it happen that the speed of light relative to an observer cannot be increased or decreased if that observer moves towards or away from a light beam? Einstein states that he wrestled with this problem over a lengthy period of time, to the point of despair."

The wrestling was fruitful: Einstein discovered that, when the observer is moving with speed v away from a light source emitting a series of pulses (the distance between subsequent pulses is D), the frequency he measures is:

f' = c/D - v/D = (c-v)/D

and the speed of the pulses relative to the moving observer is:

c' = D(f') = c - v = c

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http://www.cmmp.ucl.ac.uk/~ahh/teach...24n/lect19.pdf
Tony Harker, University College London: "The Doppler Effect: Moving sources and receivers. The phenomena which occur when a source of sound is in motion are well known. The example which is usually cited is the change in pitch of the engine of a moving vehicle as it approaches. In our treatment we shall not specify the type of wave motion involved, and our results will be applicable to sound or to light. (...) Now suppose that the observer is moving with a velocity Vo away from the source. (....) If the observer moves with a speed Vo away from the source (...), then in a time t the number of waves which reach the observer are those in a distance (c-Vo)t, so the number of waves observed is (c-Vo)t/lambda, giving an observed frequency f'=f(1-Vo/c) when the observer is moving away from the source at a speed Vo."

If in a time t the number of waves which reach the observer are those in a distance (c-Vo)t, then, according to special relativity, the speed of the waves relative to the observer is:

c' = (c - Vo)t/t = c - Vo = c

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http://www.einstein-online.info/spotlights/doppler
Albert Einstein Institute: "The frequency of a wave-like signal - such as sound or light - depends on the movement of the sender and of the receiver. This is known as the Doppler effect. (...) In the above paragraphs, we have only considered moving sources. In fact, a closer look at cases where it is the receiver that is in motion will show that this kind of motion leads to a very similar kind of Doppler effect. Here is an animation of the receiver moving towards the source: (...) By observing the two indicator lights, you can see for yourself that, once more, there is a blue-shift - the pulse frequency measured at the receiver is somewhat higher than the frequency with which the pulses are sent out. This time, THE DISTANCES BETWEEN SUBSEQUENT PULSES ARE NOT AFFECTED, but still there is a frequency shift: As the receiver moves towards each pulse, the time until pulse and receiver meet up is shortened. In this particular animation, which has the receiver moving towards the source at one third the speed of the pulses themselves, four pulses are received in the time it takes the source to emit three pulses."

"Four pulses are received in the time it takes the source to emit three pulses" means that the speed of the pulses relative to a stationary (with respect to the source) receiver is c=3D/t while the speed of the pulses relative to the moving receiver is c'=4D/t, where D is the distance between subsequent pulses and t is "the time it takes the source to emit three pulses". According to special relativity, the speed of the pulses relative to the moving receiver is:

c' = 4D/t = c + D/t = c

Needless to say, the calculation c + D/t = c is equivalent to 6 - 3 = 6, the fundamental calculation of special relativity:

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http://physics.bu.edu/~redner/211-sp...9_doppler.html
Professor Sidney Redner: "The Doppler effect is the shift in frequency of a wave that occurs when the wave source, or the detector of the wave, is moving. Applications of the Doppler effect range from medical tests using ultrasound to radar detectors and astronomy (with electromagnetic waves). (...) We will focus on sound waves in describing the Doppler effect, but it works for other waves too. (...) Let's say you, the observer, now move toward the source with velocity vO. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vO. The frequency of the waves you detect is higher, and is given by: f'=v'/(lambda)=(v+vO)/(lambda)."

"Relative to you, the waves travel at a higher speed: v'=v+vO." In Divine Albert's world, this could only be true for waves other than light waves. For light waves (v is replaced by c) Einsteinians apply the fundamental calculation of special relativity and the waves always travel at the same speed c relative to the moving observer:

c' = c + vO = c

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In the following video the observer starts moving with speed v away from the light source. One clearly sees that the speed of the wavecrests relative to him decreases (shifts from c to c'=c-v) and, accordingly, the frequency measured by the observer decreases as well (shifts from f=c/L to f'=(c-v)/L=f(1-v/c), where L is the wavelength):

http://www.youtube.com/watch?feature...&v=EVzUyE2oD1w
"General Relativity: Light in Gravity Fields"

Einsteinians also see that the speed of the wavecrests relative to the observer shifts from c to c'=c-v but then apply the fundamental calculation of special relativity:

c' = c - v = c

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