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The Science of Homeopathy – page 59

more elegant by unifying the concepts of both charges and currents and electric and magnetic fields. Since all motion is relative, every charge can also appear as a current – in a frame of reference where it moves with respect to the observer – and consequently, its electric field can also appear as a magnetic field. In the relativistic formulation of electrodynamics, the two fields are thus unified into a single electro- magnetic field . . .

Matter and empty space – the full and the void – were the two fun- damentally distinct concepts on which the atomism of Democritus and of Newton was based. In general relativity, these two concepts can no longer be separated . . .

Thus modern physics shows us once again thai material objects are not distinct entities, but are inseparably linked to their environment; that their properties can only be understood in terms of their interaction with the rest of the world. According to Mach’s principle, this interaction reaches out to the universe at large, to the distant stars and galaxies. The basic unity of the cosmos manifests itself, therefore, not only in the world of the very small but also in the world of the very large; a fact which is increasingly acknowledged in modern astrophys- ics and cosmology . . .

The unity and interrelation between a material object and its en- vironment, which is manifest on the macroscopic scale in the general theory of relativity, appears in an even more striking form at the sub- atomic level. Here, the ideas of classical field theory are combined with those of quantum theory to describe the interactions between subatomic particles. Such a combination has not yet been possible for the gravitational interaction because of the complicated mathematical form of Einstein’s theory of gravity; but the other classical field theory, electrodynamics, has been merged with quantum theory into a theory called ‘quantum electrodynamics’ which describes all electromagnet- ic interactions between sub-atomic particles. This theory incorporates both quantum theory and relativity theory. It was the first quantum- relativistic model of modern physics and is still the most successful.

The striking new feature of quantum electrodynamics arises from the combination of two concepts; that of the electromagnetic field, and that of photons as the particle manifestations of electromagnet- ic waves. Since photons are also electromagnetic waves, and since these waves are vibrating fields, the photons must be manifestations of electromagnetic fields. Hence the concept of a quantum field, that is, of a field which can take the form of quanta, or particles. This is indeed an entirely new concept which has been extended to describe all subatomic particles and their interactions, each type of particle