Displacement Current

Displacement Current lost

Ivor Catt 4sep03

I am reluctantly coming to accept that accredited experts worldwide have little grasp of electromagnetic theory. This means that, instead of taking the discipline forward, I first have to teach the classical fundamentals.

However, the challenge does not end there. I also have to give evidence that I am accurately outlining the lost theory, supplying evidence from books published before the decline. Today’s lecturer and student does not have access to such books, which have been removed from libraries around the world.

A key foundation stone for classical electromagnetism is displacement current. I shall justify that assertion, because it receives little mention in today’s text books, none of which is intelligible. (Therefore today’s lecturers and students will not already know that fact.)

James Clerk Maxwell, “A Treatise on Electricity and Magnetism” vol. 1, 1873, pub. Clarendon, Oxford, 1891, 1998, p253; “One of the chief peculiarities of this treatise is the doctrine which it asserts, that the true electric current …., that on which the electromagnetic phenomena depend, is not the same thing as [i], the current of conduction, but that the time-variation of D, the electric displacement, must be taken into account in estimating the total movement of electricity, ….”

G. W. Carter, Professor of Electrical Engineering in the University of Leeds, “The Electromagnetic Field in its Engineering Aspects”, pub. Longmans 1954/59, p262; “It was a leap of genius on the part of Clerk Maxwell to surmise that it was I + dD/dt, and not simply I, which sets up a magnetising force and is connected with it through the magnetic circuit law. [Carter then quotes Maxwell as above.]

I will follow with my own discussion about Displacement Current first arose, backed up by sections from standard text books of half a century ago discussing displacement current intelligibly. Not that this anecdote has never been challenged by today’s ignorant text book writers and lecturers. They only go so far as to not teach it.

For my version of the story, go to the first half of my article entitled “Waves in Space”, in Wireless World, March 1983, at www.ivorcatt.com/3803.htm .

.

Comments on the article “History of Displacement Current”, Wireless World March 1979 can be found at the bottom of that article.