Le Chaud Lapin wrote in
oups.com:

On Oct 6, 12:45 pm, wrote:
Le Chaud Lapin wrote:

On Oct 6, 6:38 am, Matt Whiting wrote:
Really? Many books still can't agree on the definition of
current. Some say it is the movement of electrons and some say it
is the movement of positive charge and some say it us both.
Which is the absolute truth, Mr. Wizard?
The truth is that the electrons move, not the protons.

You've fallen into the trap you are complaining about and providing
a simplistic answer that isn't true under all circumstances.

Uh...no. The difference, as I pointed out with great redunancy in my
post, is that, in one case, there are two situations:

1. The truth, which the observers know.
2. The untruth, which the obsevers concoct to make the math simpler,
all the while keeping in mind what the truth is.

This is what happens with semiconductors.

In the other case, there is only one situation:

1. What the observers think is the truth.

In this latter case in aerodynamics, the observers do not say, "We all
know that this is not what is really happening..". Instead, they say,
"This is what's happening."

I can think of no mechanism to move protons in a solid, but they
move quite well in a vacuum.

Yes, I know. When I was tutoring electrodynamics, I used the problem
that I am sure you are familiar with, a proton, entering a uniform
magnetic field, and one must find the radius of its circular motion
based on the mass of the proton, the magnetic field intensity, etc.
This problem is so common, I decided to use a proton instead of an
electron to try to catch students who were cheating by simply copying
problems from previous years. The answer given by cheaters would have
the right radius but the wrong direction.

Ever heard of a proton accelerator?

Yes, in fact, I had it as a disclaimer in my original post, just as I
had a disclaimer about a capacitor not being negative. [Note I said
that capacitors have positive capacitance, which is true, until you
start implementing virtual capacitors using general impedance
converters, which can make them negative, but then they are not real
capacitors, etc.] I took out counterexample about proton accelerators
because Wikipedia did not have an immediate link for the exact phrase
"proton accelerator", and the related links were bordering on quantum
physics, and I certainly don't want to open up a can of worms about
quantum physics in this group.

A current flow in a proton accelerator is a current flow of protons.

Sure. But no one ever disputed that. Matt was implying that electrical
engineers/physicist cannot agree on what is actually going on, which
is not true. Most physicists who work with proton accelerators are
quite aware that that there is a proton moving under the influence of
the Lorentz force in an accelerator. No particle physicist ever
claims otherwise. Also, if you ask a bunch of electrical engineers,
"Does everyone that every know that there really is no such thing as a
hole, that it is in fact massive numbers of protons, entering an
exiting the energy band according to a stochastic model?" They would
say, "Yes, yes, we know! Now get on with your talk about these non-
existent holes."

Aerodynamics, today, is different. If you ask a bunch of aeronautical
engineers, "Does everyone know that the lift is due to the air on top
traveling faster than the air beneath, thus invoking Bernoulli's
Principle..yada yada....",


You are a liar,. You've never asked anyone at Nasa anything.

Bertie