Re: "Charged" capacitor mis-terminology

["Rauber, Joel Phys" <RAUBERJ@mg.sdstate.edu>]

>    I like all these semantic traps people seem to be building for
> themselves.....  Let's see I have a time varying current of electrons
> flowing into a capacitor.  Between the plates I have a time-varying
> electric field that I want to call a current (to make the current appear
> continuous through the capacitor).

If this were the only reason for defining displacement current; then it 
would merely be a mathematical convenience; which is not necessarily bad! 
 But it is not the only reason, another reason is that a flux of changing 
electric field produces the same affect on compass needles that a flux of 
leptons through a copper wire produces.  Another reason, is its requirement 
in Maxwell's equations to maintain the charge continuity equation.

> The only problem for an old nuclear
> physicist like myself is that my current of leptons in the wire suddenly
> turned into a current of bosons between the plates.  Oh oh....

Don't you have this same problem when looking at the conduction current in 
chemical cells?  I am looking at a diagram in my college chemistry text of a 
galvanic cell, where the current in the "wire" part of the circuit appears 
to be electrons (leptons) and elsewhere the current appears to be, in part, 
positive ions.

The generalization of current to two types, conduction and displacement; is 
*not* a claim that leptons change into bosons.  It is *only* a 
generalization and makes no claim that conduction current and displacement 
current are isomorphic to each other.

Incidently, when you introduce electric fields to your introductory 
students, how do you argue that the electric field has objective reality 
rather than being simply a mathematical convenience?

> from Fullerton, which is pretty close to Disneyland (why do I feel that
> I'm in the magic kingdom?)

no comment,      :-)

Joel Rauber