published in the IEE Journal " Electronics & Communication Engineering Journal " October 1995, p218.
by Ivor Catt
Westfields Press 1994
"The main body of the text is devoted to transmssion lines ....
There are numerous examples of sloppy argument in the text. .... The flaws in these arguments are easy to see. ....
The 'Catt anomaly': When a TEM wave travels along a transmission line, there must, according to conventional theory, be charge distributions on the surfaces of the conductors behind the wavefront. For a vacuum dielectric the speed of the wavefront is the speed of light so that, according to Catt, the charges on the conductors must travel at the speed of light, which is impossible. This is the 'Catt anomaly'. Since the wavefront does travel at the speed of light, so do the charges, which then have infinite mass. It follows that there cannot be charges on the conductor surfaces and conventional theory must be wrong.
The flaw here is the assumption that the charges move with the wave. whereas in reality they simply come to the surface as the wave passes, and when it has gone they recede into the conductor. No individual charge moves with the velocity of the wave. The charges come to the surface to help the wave go by and then pass the task to other charges further along the line which are already there and waiting. This is the mechanism of guidance and containement. There is no anomaly.
But Catt goes on. Having removed charges from the surfaces of his conductors, he can no longer apply Gauss's law and the displacement current in the wave has to go somewhere. Catt's solution is typically ingenious: the current must continue as displacement current in conductors, which are actually dielectrics with a very high permittivity; there is no conduction current in conductors - ever! Catt's Ockham's Razor has been wielded to remove conduction current as well as electric charge from electromagnetic theory. There is of course the small problem of a value for the permittivity of copper. Catt is equal to the challenge .... the permittivity of copper must be extremely large. ....
.... It is significant that, having introduced his new theory and abolished charge and current ...., he then proceeds to use these concepts quite unashamedly in the rest of the book. ....
There are many other items in this book which give cause for concern, for example the false statement that 'The TEM wave has virtually disappeared from today's electromagnetic theory'.
Catt's belief in his own work is clearly sincere, but this reviewer, after lengthy and careful consideration, can find virtually nothing of value in this book.
The penultimate paragraph above echoes Lago's earlier letter in Wireless World (July79) where he attacked my articles "Displacement Current" that appeared in Wireless World, Dec78 and March79:-
Lago has surfaced just twice with his large spanner. I know nothing of him except that he is at Keele University.
-Ivor Catt feb01
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