Einsteinís theory of relativity was dealt with very briefly in my university course but we were told that we must not expect to understand it. I accepted this situation and I have since discovered that most physicists are content to remain in the same position assuming that it must be right because it is generally accepted. My doubts about it arose when I found that the experts did not understand either. An exchange of letters in Nature between Dingle and McCrea showed that they had opposite views about some of the predictions of the theory and the arguments advanced on both sides were in my view illogical and unconvincing. Much of the discussion about the theory was concerned with the readings of clocks when they are moving relatively to each other, and since I had a wide experience of comparing clocks and measuring time it seemed to be almost a duty to take a closer interest in the controversy especially as some of the so-called relativity effects although very small were not becoming significant in the definition of the atomic second and the use of atomic clocks.
It is always better to refer to the original papers rather than to second hand accounts and I, therefore, studied Einsteinís famous paper, often regarded as one of he most important contributions in the history of science. Imagine my surprise when I found that it was in some respects one of the worse papers I had ever read. The terminology and style were unscientific and ambiguous; one of his assumptions is given on different pages in two contradictory forms, some of his statements were open to different interpretations and the worst fault in my view, was the use of thought-experiments. This practice is contrary to the scientific method which is based on conclusions drawn from the results of actual experiments. My first thoughts were, that in spite of its obvious faults of presentation, the theory must be basically sound, and before committing my criticisms to print I read widely round the subject. The additional reading only confirmed my belief that the theory was marred by its own internal contradictions. Relativitists often state that the theory is accepted by all scientists of repute but this is quite untrue. It has been strongly criticised by many scientists, including at least one Nobel prize winner. Most of the criticisms are of a general nature drawing attention to its many contradictions, so I decided to pin-point the errors which give rise to the contradictions, giving the page and line in Einsteinís paper, thus making it difficult for relativitists to dodge them and obscure them in a morass of irrational discussion.
There were definite errors about which there can be no argument. One was the assumption that the velocity of light is constant. This is contrary to the foundations of science and the fact that it is repeated in all the textbooks I have seen, shows how little these foundations are understood by theoretical physicists. Science is based on the results of experiment and these results must be expressed in a single coherent set of units. The unit of length was the metre and the unit of time was the second. Velocity was a measured quantity as so many metres per second. Even though it was found to be constant under certain conditions, it was quite wrong to make it a constant by definition under all conditions. Only the unit of measurement can be made constant by definition and Einsteinís assumption constituted a duplication of units. It was this duplication that led to puzzling and contradictory results and not the profundity of the theory as relativitists like us to believe.
The question of units is a rather complicated one; and in this instance some writers are confused by the fact that the velocity of light is now often used as a standard, distances being calculated from the time of travel of a pulse of light or radio waves; but the value used is the measured value and the conditions of measurement are carefully defined. Quite recently a further complication has arisen. At the end of our work at the NPL we made the suggestion that as the techniques improved it might be advantageous to redefine the units of measurement, keeping the atomic second, giving a defined value to the velocity of light and discarding the unit of length. This has now been done, but these developments do not affect the criticisms of the theory. Even with these units it would still be absurd to assume that the velocity would be the same for two observers in relative motion. Units must be used with common sense.
The other glaring mistake occurred in the course of one of his thought experiments. Einstein had never made any actual experiments, as far as I can find, and he certainly had no idea of how to compare clocks. He imagined two identical clocks side by side and supposed one of them to move away at a uniform velocity and then return. According to one of the results deduced from the theory a moving clock appears to go slower than the stationary one when viewed from the stationary position. Calling the clocks A and B the predictions are:
B is slower than A as seen from A
and since velocity is only relative and either of the clocks can be regarded as the moving one:
A is slower than B as seen from B
This is certainly strange although not logically impossible. It implies that something happens to the signals during their transmission. He then outlines his experiment without giving any details of how the measurements are made and concludes that:
B is slower than A
and although he does not specifically say so:
A is slower than B
in accordance with the relativity principle.
This result is of course impossible, and is usually called the clock paradox. Many thousands of words have been written about it, but the explanation is simply that he did not go through the correct procedures in making his experiment. It is a very simple experiment, being carried out every day in clock comparisons, and the correct result agrees with his predictions as indeed it must do since a thought experiment cannot give a new result. The predictions themselves are also inexplicable but this is one of the consequences of the duplication of units.
I had rather naively thought that scientists would be glad to have an explanation of the confusion which had existed for so long and would at least pay some attention to my explanation, since I had more practical experience in these matters than all the relativitists put together. But I was wrong. No one attempted to refute my arguments although they justified Einstein by repeating his thought experiment and his mistakes in different forms. I was, however, dropped some pretty broad hints that if I continued to criticise the theory my reputation and career prospects were likely to suffer. It was only a sideline to my experimental work but I found it so interesting that I did not feel like dropping it, and felt that it was very important that the theory should be exposed. My Director was good about it and said he had no objection himself as long as I did not involve the NPL. I was beginning to realise that scientists could be just as irrational as anyone else and having accepted the theory as a faith without understanding it they closed their minds to argument. They also tried to suppress opposition and two of my papers after being accepted by the referees were mysteriously never published.
I was not entirely without support and was invited to write an article by the Oxford University Press. It was not so comprehensive as they hoped, since I was not able to devote as much time to it as I would have liked, and lacked the secretarial assistance of my department, but it was accepted and published as one of their Research Papers (No. 5). The Director of the Royal Institution also invited me to give one of their Friday Evening Discourses. This was quite enthusiastically received and I had many letters of congratulation, although, as I noticed with some amusement, most of them were written on private notepaper and not on the paper of their organisations as one would normally expect.
The history of relativity would make a fascinating study and I regret that I do not feel competent to do it myself. I have kept to those aspects dealing with units of measurement and the comparison of clocks which I know something about. It was inspired by the puzzling results of an experiment made by Michelson and Morley. They argued that if light travelled at a steady velocity through the medium, or aether, and the surface of the earth was moving through this medium there should be a detectable effect on the movement, but they failed to detect any. Fitzgerald and Lorentz gave an empirical explanation that moving rods were shortened and moving clocks were slowed down. Scientists badly wanted a more detailed satisfactory explanation and this is what Einstein thought he had done. All he did was to introduce irrational ideas into physics and incorporate the Lorentz explanation into electromagnetic theory as an assumption. The original puzzling results, therefore, remain and it is important to science that a true explanation should be found.
The famous paper published in 1905 does not appear to have attracted any attention until Eddington returned from an expedition to study the eclipse in 1919, and with great publicity announced to a meeting of the Astronomical Society in London that the results had proved Einsteinís theory. What he thought he had confirmed was Einsteinís value for the bending of light round the sun. Scientists were prepared to go to a lot of trouble to obtain experimental evidence for the theory as they realised that this was necessary and yet Eddington is supposed to have said that the theory was so satisfactory that if the experimental results did not confirm it then they must be wrong. A criticism of the results made later pointed out that in order to obtain the result he wanted, some of the observations which did not fit were ignored. Also someone has pointed out, with some evidence, that Einstein himself had predicted two results differing by 2 to 1 for the deflection. Finally the deflection of the sunís rays has nothing to do with the special theory and the clock paradox and yet in some mysterious way it was claimed to confirm it. Still searching for experimental support an experiment was made in the US some years ago. Four atomic clocks were carried by plane in opposite directions round the world. The discrepancies between the results for different clocks were many times greater than the effect being sought, and yet by ignoring the results they did not like and performing some undescribed statistical analysis the authors claimed to have confirmed Einsteinís theory and specifically the clock paradox. There was a spectacular television programme about it in which a well-known actor was installed in a simulated space shuttle and told that he would come back younger than if he had stayed on earth. Being an intelligent man he appeared to regard it as a lot of nonsense as I hope the viewers did.
My intrusion into theoretical physics must be regarded as a failure in that I did not convince the relativitists of their mistakes. It may have had some benefit in encouraging scientists to look for a rational extension of electromagnetic theory to explain the many mysteries not yet explained. There have been several attempts, that of Rene L Vallťe being in my view particularly encouraging. It is a unified field theory giving an electromagnetic explanation of gravitation, and including a most important suggestion that it might be possible to harness the gravitational energy of space safely and economically. He argued that the nuclear energy programme in France was wasteful and misdirected and was in consequence obliged to leave the authority for which he worked. It is sad if his ideas were not fully studied because the nuclear fusion programmes throughout the world seem to make little progress in spite of the billions spent on them.