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http://en.wikipedia.org/wiki/Maxwell's_equations . From Wikipedia on Maxwell's Equations "[edit] The term Maxwell's equations The importance of Maxwell's role in these equations lies in the correction he made to Ampère's circuital law in his 1861 paper On Physical Lines of Force. He added the displacement current term to Ampère's circuital law and this enabled him to derive the electromagnetic wave equation in his later 1865 paper A Dynamical Theory of the Electromagnetic Field and demonstrate the fact that light is an electromagnetic wave. This fact was then later confirmed experimentally by Heinrich Hertz in 1887." Here we see the idea that the conept of Displacement Current was needed to derive the idea that light is electromagnetic. Once it is accepted that there is a current, displacement current, in free space, then Ampere's Law is used to show that the electric field, (which produces displacement current) can produce a magnetic field. Thus the loop is completed. Already by Faraday's Law magnetic field in space could create electric field. Now electric field creates magnetic field. This leads to "The Rolling Wave" . In this context, it is useful to doggedgly ignore the relative phases of E and H - that they are in phase - or the whole idea is put at risk. How could two fields which rise and fall together be the cause of each other? Here we see the implicit outlawing of "The Heaviside Signal" , the slab of energy current which travels forward unchanged at the speed of light. The TEM Step (logic transition from zero t onje) travelling unchanged at the speed of light from one logic gate to the next is incompatible with the Wikipedia idea that a TEM Wave, or light, has to have an oscillatory (sinusoidal) amplitude to make it possible to travel forward at the speed of light. Thus, the sinusoidal story for the electromagnetic wave is incompatible with virtually all of today's electronics, which is digital. In the case pf "The Heaviside Signal" , the electric field and the magnetic field are complementary, coexistent. From this point of view, the idea that E causes H causes E would be like saying that the width of a brick causes its length which in turn causes its width. The truth is, that for a brick to exist, it must have width and length. Similarly, for a TEM Wave to exist, it must have E field and H field. It is a very thin two dimensional wave which travels in the third direction at the speed of light. In a universe where there is no instantaneous action at a distance, the wafer does not know whether there are further wafers ahead of it and behind it, making up a full pulse. @@@@@@@@@ http://en.wikipedia.org/wiki/Electromagnetic_wave . From Wikipedia on Electromagnetic Waves "Electromagnetic waves were first postulated by James Clerk Maxwell and subsequently confirmed by Heinrich Hertz. Maxwell derived a wave form of the electric and magnetic equations, revealing the wave-like nature of electric and magnetic fields, and their symmetry. Because the speed of EM waves predicted by the wave equation coincided with the measured speed of light, Maxwell concluded that light itself is an EM wave. According to Maxwell's equations, a time-varying electric field generates a magnetic field and vice versa. Therefore, as an oscillating electric field generates an oscillating magnetic field, the magnetic field in turn generates an oscillating electric field, and so on. These oscillating fields together form an electromagnetic wave." This is diametrically opposed to Figures 4, 5 in my book. or Forrest Bishop's animations . . In my book we see a TEM Wave, which is an electromagnetic wave,
with no oscillation, and therefore no possibility that changing
E field causes H field and vice versa. In the centre of the step,
or pulse, there are no changing fields, and yet we know that it
travels forward at the speed of light.
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