Bruce Harvey's Alternative Physics site

The light clock fiddle


Einstein, time dilation, Lorentz transforms
The light clock is an imaginary device for measuring time in an absolute way. It does not have any moving parts, but simply relies on a pulse of light being continually reflected backwards and forwards between two mirrors. It depends on nothing except the speed of light and the distance between the mirrors for its accuracy.

Einstein concludes from the null result of the Michelson-Morley experiment that all observers will measure the speed of light to be the same. On this basis he assumes that the light clock will provide a moving observer with a reliable method of measuring time.

The Lorentz time dilation equation can be derived using the concept of a light clock which is reflecting light backwards and forwards perpendicular to the direction of relative velocity of two observers. One observer owns the light clock and sees the light pulse moving backwards and forwards between the same two points. The other sees the light pulse moving in a zigzag fashion between the moving mirrors of the others light clock. The length of each leg of the zigzag path is greater than the distance between the two mirrors. If both observers are to measure the same universal speed of light, then time must be slowed in one observer's system relative to the other observer's system. In practice a light clock will not work, but we have laser distance measurers which have a source and a separate detector built into the one device. We might imagine such a device and a mirror as a form of light clock.

Let us call the observer who does not own this light clock the onlooker. He will see the apparatus as if the source and detector are separate devices. With a simple bit of trigonometry which is in all the text books which describe this situation, we can derive the Lorentz equation.

Where these are time intervals. The ticktock of the light clock appears to the onlooker to take longer than it does for the owner. That means that the owners clock appears to the onlooker to run slow.

The onlooker might set up a similar arrangement, but with a separate source and detector and arrange things so that the two sets of apparatus pass over each other and are triggered so that two light pulses move together when viewed from above. This would allow the two observers to swap rolls and consider how long the light pulse of the onlooker's apparatus takes to do its ticktock. Now the one who does not own the new apparatus observes the ticktock to take less time. The symmetry has been broken.

The result depends on the angle of the light pulse to the direction of the two observers relative motion. The choice of the light clock and its orientation arbitrarily selects a particular direction which gives the correct result. We do not prove that the square of the longest side of any triangle is equal to the sum of the squares of the other two sides by drawing a right angled triangle, proving that it works in that case and then generalising. That is mathematically unsound and it is mathematically unsound to pick a particular direction for the light pulse to travel in when the result depends on the direction. In short, it is a mathematical fiddle.

Now the proponents of special relativity will come back at me and claim that there is also a question of synchronisation of clocks and that if we take that into account, then we get consistent results. But is their logic correct. It seems to me that there are two choices; either the speed of light is not always the same for all observers, or it is, and there is some other strange effect taking place. The logical thing to do is to run the logic from each of these possibilities along their respective thought trains and see where that takes us. We will eventually reach a point where one thought train contradicts experimental results and we can conclude that it is based on a false premise. The proponents of special relativity do not do this, but stick to an irrational belief in the constancy of the speed of light and the equality of status of all observers, because of its intrinsic simplicity and beauty.

The light clock deduction shows us that two observers in relative motion will both observe the others clock to be running slow. This has to be an artefact of the act of observing moving systems. The result is symmetric because both observers have equal status. If they both have equal status, then their clocks cannot actually run at different rates because that would imply that one was faster than the other breaking the equality of status. That is where the logical train of thought takes us from the assumptions of special relativity. The problem is that the clock actually does slow down. The muon created in the earth's outer atmosphere makes it to the ground because its clock actually slows. When we fly a clock round the earth at high speed, it looses time. We imagine that a twin who goes to the nearest star and back will return younger than her earth bound brother, but the experiment is impossible to carry out. The experimental evidence is that high speed motion of clocks relative to their environment actually slows them down. That contradicts the equal status assumption of relativity.

Again, the proponents of relativity will come back at me and say the the act of acceleration rotates the orientation of the observer to space time and causes the effects of changes in the synchronisation and speed of time. The there and back trip will have a real effect on the age of the twin who travels there because the two rotations of space time occur at different places and the discrepancy is really due to the effect of this on the synchronisation of time for the two twins. Have they not read elsewhere in their theory that the effect of gravity is something we experience because we are in an acceleration field. If it is true that the twin accelerating away from the solar system at 10m/s/s is undergoing a shift in time synchronisation, then so are we according to the general theory of relativity. This is blatantly not the case. The experimental evidence comes from the moon and mars missions where the difference in gravity should result in a major de-synchronisation of time if the basic assumptions of relativity are true.

The new theory of electricity and magnetism which I have developed predicts that observers will not have equal status. The experiments which we can perform to test the theory of relativity are based on unequal status in that motion must be relative to the earth's surface. The success of special relativity relies somewhat on the fact that unequal status is unknowingly built into its derivation. The light clock derivation cannot give the two observers equal status because one of them has to own the light clock which the other observes it to be running slow. The very act of drawing the diagram violates the principle of equal status. It is like doing geometry with a curved ruler.

Special Relativity
Relativity and the nature of time
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© Copyright Bruce Harvey 1997.