Does Space Insulate or Conduct?

[upriver]

Charge is part of the electron and kinetic energy is not.

The interesting thing is that magnetic fields dont appear until you add kinetic energy to a charge in the case of EM.

Yes, that is true...

Still having difficulty with your understanding of "kinetic" energy.

If an electron is mass, then my understanding of "kinetic" energy is that it requires mass and that mass be moving.

What understanding of a permanent magnet do you hold? What is the magnetic field?
From what we have evolved to, there must be mass, moving.?

Kinetic energy requires mass to express itself.
Its like gas for an auto that requires an engine to express itself as velocity. Its not part of the auto but its something you add to it. It requires both components.

Permanent magnets are atoms with lined up spins...

[Sparky]

Permanent magnets are atoms with lined up spins.

Yes, but what is the field? Is it some type of kinetic flow?

[vari]

I don't get why this topic has been stretched out for this many pages without any real consensus of what is going on.

Space really is both a perfect conductor and a perfect insulator. Why? It all depends on your definition.

Charge can move from atom to atom. Or it can travel as a charged particle in empty space (once it has escaped the structure it was confined to).

Take two electrodes in space and have a potential difference. Only once the potential difference is big enough to break the electron out will it exit the other pole and be carried by the EM field to the other pole. This can be mitigated by heating up the electrode.

Now add conducting particles into that empty space - the charge will want to use those particles to conduct it self because it is much faster to conduct through matter than to drift through nothingness. Nature optimizes everything.

[Lloyd]

That's what is contested: whether matter improves or hampers electric conduction. You may be right about it depending on definitions etc, but CC showed that the less matter in the upper atmosphere, the greater the conductivity. He seems to think that matter hampers conduction. I guess everyone would agree that positive and negative charges attract while like charges repel.

[vari]

Air is not a very good conductor, now is it? So if you have more insulator molecules in the way of the drift, then it will be harder to drift the particles across the "vacuum".

Change the molecules into something that conducts very well, say copper. And you wil find that the more you have the better it conducts. At some point with enough concentration you don't need any extra voltage difference or heating of the electrode since it will start to act as a solid conductor and conduct immediately.

edit: Note that putting only a few atoms of copper won't help since they will capture the electrons but not re-emit if they are not heated (same as with the electrode). So any material will act as an insulator for the charge drift, but once the concentration is big enough that they are allowed to conduct they start acting as a conductor.

We have to make very clear the difference of charge conductance in matter and the drift of charged particles in vacuum. Two entirely different methods of charge travel.

[vari]

It is the EM field that makes charge move. A very weak EM field can slowly drift charge through vacuum, or conduct through matter. But if there are big gaps to jump, the differential over that gap has to be big enough so the jump is possible.

Inside matter the gaps are small. The better conductor it is the smaller the gaps. But if the concentration of gas in space is very small, there will be big jumps between the gas molecules. So either you need more conductive molecules, or more energy from the EM field to make the separation and drift happen.

Space is the perfect medium for charge drift, but perfect insulator for charge conductance.

edit: to me the "issue" in this discussion seems to be a bit similar to all the other fields where no clear answer is found. Take voting systems for instance. There is an endless discussion what is the best/fairest/etc voting system. While the truth is that no voting system is fair, since every voting system is by definition (as we have adopted it) faulty. Range voting avoids all voting paradoxes, making it the perfect voting system, yet by current definition it is not a voting system.

They have you running in circles by design.

[Lloyd]

Can you summarize what your answer is then? Do you know of data on the conductance in vacuum? Charles showed earlier data on the conductance at high altitudes where the air gets very thin, maybe equivalent to a vacuum on Earth or nearly. The conductance got higher as air density decreased. Do you know if the electric field at such altitudes is very strong to account for the conductance?

Do you know of a chart that may show the conductance within a range of E-field strengths and within ranges of the other parameters?

You said: "Space is the perfect medium for charge drift, but perfect insulator for charge conductance."

Does that tell you anything about galactic electric currents? And does it suggest that the Sun is connected to and powered by a galactic electric current?

[CharlesChandler]

So any material will act as an insulator for the charge drift, but once the concentration is big enough that they are allowed to conduct they start acting as a conductor.

We have to make very clear the difference of charge conductance in matter and the drift of charged particles in vacuum. Two entirely different methods of charge travel.

Exactly. But for whatever reason, we don't seem to have the terminology to describe electric currents in space. So people try to apply EE concepts, thinking that for currents to flow, there has to be a conductor there. This has led to the mistaken impression that currents favor denser plasma, and that plasma filaments in space are acting like extension cords. The reality is that currents favor thinner plasma, and then they evacuate the remaining particles in that plasma, to the limits of the external hydrostatic pressure, given the current density. The instability responsible for an insulator to break down is that the current flows better through a thinner medium (all other factors being the same), and the current can further thin out the medium with particle collisions, which enhances the current density. The extreme current density in a lightning strike here on Earth is flowing through a near perfect vacuum, which wouldn't happen if a vacuum was a resistor.

They have you running in circles by design.

That's my opinion also. This is actually pretty simple. Only deliberate obfuscation could make it confusing. I just don't understand who thinks that physics is better obfuscated, or that they could succeed at it long-term. The truth doesn't sleep.

[Lloyd]

CC said: The extreme current density in a lightning strike here on Earth is flowing through a near perfect vacuum, which wouldn't happen if a vacuum was a resistor.
[] This is actually pretty simple. Only deliberate obfuscation could make it confusing.

It's not real clear to me. If a current is moving through space, I assume it's moving toward the nearest or strongest opposite charge concentration, although bipolar jets are currents too, aren't they?, and they're moving away from the poles of a body, rather than toward opposite charge, I guess. The theoretical galactic current in the EU model, is it supposed to be moving toward an opposite charge concentration? It doesn't seem so.

I heard that AC current moves on the surface of conductors, while DC moves within conductors. Do you agree? Would there be vacuum channels in either of those locations?

[CharlesChandler]

If a current is moving through space, I assume it's moving toward the nearest or strongest opposite charge concentration, although bipolar jets are currents too, aren't they?, and they're moving away from the poles of a body, rather than toward opposite charge, I guess.

It all depends on the model. In my model of bipolar jets, ejecta from "natural tokamaks" move because of the momentum they got from the nuclear fusion going on in the core of the reactor. They are +ions, and they drag electrons along with them, in a parallel but separate charge stream. CMEs are likewise +ions, which drag electrons along with them, but CMEs typically balloon outward -- they don't stay collimated like bipolar jets, so they don't drag a parallel but separate stream of electrons along with them. Rather, CMEs simply increase the voltage between the Sun and the heliosphere, which increases the electron drift out of the photosphere.

The theoretical galactic current in the EU model, is it supposed to be moving toward an opposite charge concentration? It doesn't seem so.

I don't know -- I haven't heard anybody say specifically.

I heard that AC current moves on the surface of conductors, while DC moves within conductors. Do you agree?

I think that all currents (AC/DC) flow on the surface of the conductors.

Would there be vacuum channels in either of those locations?

That depends on who you're talking to. Most EEs don't seem to acknowledge any sort of vacuum between atoms in the crystal lattice of a conductor -- they think of the whole thing at a higher granularity, where the valence bands have fused into a continuous conductor, and the electron cloud is free to slosh around all it wants. But if you step down one notch in granularity, you see the atoms, and the electron shells, and the void between the atoms. So every time an electron hops from one atom to the next, it has to exceed the work function of the previous atom (as if it were an electrode) to get out of that electron shell and into the next one. But it does this easily, because the atoms are close enough together that all of the electric forces are superposing, so the shells present little resistance. At the end of the conductor -- at the electrode staring off into a vacuum -- there is no next atom to hop onto, so the electron somehow has to be broken completely out of the valence band of the conductor. That takes additional work (known as the work function of the electrode). But that doesn't mean that the vacuum is providing "resistance" -- it's just that the crystal lattice came to an end, and the binding energy of the electrons inside the conductor had to be overcome. Once this happens, the electrons can drift through the vacuum unimpeded.

[vari]

This may be off topic but i would like a quick comment on what you posted:

I think that all currents (AC/DC) flow on the surface of the conductors.

To my understanding the higher the frequency is, the more the charge is forced to the surface of the conductor. Would this not mean that with DC there is zero such forcing, making the whole conductor conducting?

I would think that this effect is caused by the change in current direction. Since a field forces the particles to some direction, and when the field changes ever more frequently, the sum total is a force in both directions = expanding the volume. By the thumb rule you get a radial field from a current.

That same field is present in a constant current, but when you think about it the effect is biggest when the current is zero. The current is zero when voltage is zero in AC (lets not take into account inductance). So the more such event you have the more effect of the radial field is felt. And the more hz you have, the more such events you have in same time interval.

[JeffreyW]

This may be off topic but i would like a quick comment on what you posted:

I think that all currents (AC/DC) flow on the surface of the conductors.

To my understanding the higher the frequency is, the more the charge is forced to the surface of the conductor. Would this not mean that with DC there is zero such forcing, making the whole conductor conducting?

I would think that this effect is caused by the change in current direction. Since a field forces the particles to some direction, and when the field changes ever more frequently, the sum total is a force in both directions = expanding the volume. By the thumb rule you get a radial field from a current.

That same field is present in a constant current, but when you think about it the effect is biggest when the current is zero. The current is zero when voltage is zero in AC (lets not take into account inductance). So the more such event you have the more effect of the radial field is felt. And the more hz you have, the more such events you have in same time interval.

http://en.wikipedia.org/wiki/Skin_effect

[Chromium6]

This may be off topic but i would like a quick comment on what you posted:

I think that all currents (AC/DC) flow on the surface of the conductors.

To my understanding the higher the frequency is, the more the charge is forced to the surface of the conductor. Would this not mean that with DC there is zero such forcing, making the whole conductor conducting?

http://en.wikipedia.org/wiki/Skin_effect

http://en.wikipedia.org/wiki/Telluric_current
http://en.wikipedia.org/wiki/Magnetotelluric

[jone dae]

Thank you, Charles, for the link to that page about Ohm's law, a microscpic view. It is educational, and we'll probably include it on JKU.