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A New Law For Superconductors
TaleSlinger sends word of a newly-discovered "mathematical relationship — between material thickness, temperature, and electrical resistance — that appears to hold in all superconductors." The work (abstract), led by Yachin Irvy, comes out of MIT's Research Laboratory of Electronics. Researchers found that a particular superconductor (niobium nitride) didn't fit earlier models estimating the temperature at which it changes from normal conductivity to superconductivity.
So the researchers conducted a series of experiments in which they held constant either thickness or “sheet resistance,” the material’s resistance per unit area, while varying the other parameter; they then measured the ensuing changes in critical temperature. A clear pattern emerged: Thickness times critical temperature equaled a constant — call it A — divided by sheet resistance raised to a particular power — call it B. ... The other niobium nitride papers Ivry consulted bore out his predictions, so he began to expand to other superconductors. Each new material he investigated required him to adjust the formula’s constants — A and B. But the general form of the equation held across results reported for roughly three dozen different superconductors.
I like it when solutions are both simple and correct.
After lengthy analysis of the work and further experimental confirmation we may have a Nobel winner on our hands.
Do not look into laser with remaining eye.
You should really read the "abstract," because the entire paper is available there at no cost. The discovered relationship is not a*C = b, but rather x = A y ** (-B), which is a much more complex relationship, and quite startling in this arena. Also be sure to look at all his graphs so you will understand what this guy did, what he discovered, and why this is a Big Deal (tm). Then maybe you won't be so quick to mock this discovery...
You seem to have a really bad case of apples and oranges syndrome. I'm really not trying to get on your case -- rather, I want to help you understand the way things really work.
1. "for example "light" can travel faster than light if they are travelling in different mediums."
Whether you realize it or not, what you're saying here is that the speed of light depends on the medium. This is true. It seems like you are saying that this is some sort of contradiction, when in fact it isn't. Consider your own running speed: do you run faster in air or in a pool? Light faces a similar situation; in denser media it has a slower speed. Saying "light can travel faster than light" is just silly. Light always travels at the speed of light -- just not always at "speed of light in a vacuum."
2. "a vacuum has really high resistance and I seem to remember that electrons travel at different speeds depending on the resistance."
If you are talking about electron drift velocity in a conductor, then I recommend you start reading here: http://en.wikipedia.org/wiki/D.... If you are talking about the velocity of free electrons in a vacuum, that's a completely different story. A free electron in a vacuum has no single speed, no more than a free cue ball in a vacuum would have. Either object travels at a speed consistent with its momentum and energy. If you're talking about electrons shot out the back end of an accelerator, they're going close to c (the dreaded speed of light in a vacuum). If you're talking about electrons accelerated by some other mechanism, well, then the speed is going to depend on what energy the accelerator imparted to the electron.