In Reply to: Re: Current flow in a vacuum vs. current flow in cryogenic material posted by Pat McMahon on 12/20/01 at 4:07 PM:
I may get back to you with further thoughts on your questions as I have only been thinking about them for a short time but think about this:
Current flow , regardles of the temperature, requires a medium; what is the medium in a perfect vacuum? The perfect vacuum should actually be considered the perfect insulator.
(Look at defination of dielectric constant.)
In respect to your thoughts on electrons in a vacuum; are not your two conjections the same? How would you prove one is different from the other? In one case the particle travels until absorbed by the walls of the container: in the other case the wave continues until it is absorbed in the walls of the container. Also, how does your electron get into motion? What drives it? One of the laws of motion is "nothing moves unless it gets pushed" ( my apologies to Newton for the paraphase)
Getting back to your original question, if an electron were to be inserted into a "perfect vacuum" and it was to travel from one point to another( which would be considered a current flow) it would require only a difference of potential (an electric field) between the two points. The energy of the electron (its temperature) would be determined solely by the charge differential between the two points. This energy is only manifest in its kinetic force when striking the target electode. The theoretical resistance of the current flow would be proportional to the energy required to move it from one point to another. The electron does have mass no matter how small and energy is required to accelerate it. This is true whether the vacuum is "perfect" or not. The only exception being "lost" electrons due to collision with ambient gaseous elements, which would add to the resistance (in a less than perfect vacuum).
The other thing I wanted to clarify is that not all elements or alloys become "superconducting" at or near absolute zero. The list of "superconductors" is rather restrictive. Absolute zero does not equal zero resistance.
Think about the basic concepts of vacuum as being the absense of matter and of electric current as being the flow of electrons through a material. Stick to the basics.
As you read this message sub-atomic particle are jumping in and out of you body and they don't even know you are there. Our universe has a basic energy level which can and has been quantified now that our technology has been able to manufacture sensors able to detect the comings and goings of esoteric particles. It has nothing to do with the "big bang" but what we can observe here and now.
OK it's a little late and perhaps this may seem somewhat weird but consider this.
A collection of atoms is sitting around doing nothing in particular one Saturday night and suddenly out of nowhere a laser beam hits them and excites them to states they have never known. They all follow the crowd and go off on a long journey. Their universe is gone. They were just hanging around the mall and now they are off on some long jorney to who knows where. The difference is in their energy level. There simply is nothing left of them in the lower energy level. (What is left of you on the first floor when you arrive on the twentyfifth floor of your office building). How much energy would it take to obliterate you completely? (a lot). How much to take you up a few floors? (not much). How much energy would it take to obliterate the universe? (WOW!!!). How much to raise its energy level?
Thanks for the discussion.