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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're an idiot, read the damn abstract before speaking nonsense.
"I decided I could write something better than everything out there in two weeks. And I was right." - Linus Torvalds
Good thing too! If we allowed discrimination on how thick some one (or thing) was, we'd probably not allow our current batch of thick headed politicians run for office... or let people who are so thick they try to turn everything online into a political debate be able to connect to the internet!
Per Wikipedia: "Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature." According to the given formula: thickness x critical temperature = A / (sheet resistance) ^ B, that would give division by zero or am is something not clear?
I thought it was understood because it was so painfully obvious? If only I had known the world was so stupid I would have published the law myself decades ago...
On my order for one Coulomb rated supercapacitor?
Am I missing something, isn't room temp supercapacitor == post-battery world?
But a and b aren't simply real numbers. They are _variables_ that can adopt real numbers. So, a1 * C = b1, but a2 * C != b2 is of course valid. Except for the properties of superconducting materials in which case it appears to be that if a1 * C = b1 then a2 * C = b2.
Republicans will just shoot the minority superconductors.
A researcher has identified a new social law that describes exactly the probability of getting lucky, which only relies on 17 variables, each of which needs only be adjusted for each pairing of two individuals.
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...
Wait, where do you see any nonsense in my statement?
And this folks is how you do basic research and why it pays to do it!
This is very exciting. As high temp is what we are after. You can fiddle the formula and pick materials that fit the formula and hit the temp you need. This is a good clue as to what we are after. Now to find materials that hit the other parts of the formula. Or how to pick them apart to feed into this formula. Very exciting! It will be a long slog finding something that fits :)
I don't know anything about the physics of this paper.
But I love figure 3 (also highlighted at the aps.org URL),
because it highlights outliers from the theory, and points
to the supplementary information for theories about why
those points didn't fit the otherwise nice curve.
Bringing attention to errors as well as successes - that's
good honest work.
All of it.
do electrons travelling in super conductors travel faster than the speed of light?
He found a neat empirical formula that matches nature.
Does our model of how things work (QED?) fit this formula,
or do we get an opportunity for a better model?
So trying to parse the formula from the English description; [thickness] * [critical temp] = A / ([sheet resistance] ^ B), where A = [crystalline structure] * B + C
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
My (limited understanding) is no.....but fewer of them "clog the pipe" and make it to the other end (lower resistance values).
elctrons don't travel, they just pass the wave along, like waves on an ocean of water
Naming it now to save everyone else the trouble when the Nobel prize gets awarded to this person.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
No, becasue nothing does.
The wave moves cleaner. Remember, SoL is different in different mediums The constant we use ~300,000,000 meters per sec/sec is in vacuum, and close to the in superconductors.
Interestingly, the electrons gain more mass in superconductors.
The Kruger Dunning explains most post on
When I read the headline, I was immediately thinking of some artifical law regulating the production, storage, and sale of super-conductors. Of course, also regulating the export to other countries.
Sad, isn't it?
that's what made me "think the question out loud".
but you disagree with yourself.
for example "light" can travel faster than light if they are travelling in different mediums.
a vacuum has really high resistance and I seem to remember that electrons travel at different speeds depending on the resistance.
WTF? Railroad Super Conductors get preferential treatment over less than stellar ones? What lobbying group managed to get Congress to pass this?
Oh...wait...
http://arxiv.org/abs/1407.5945
Nothing with mass moves faster than photons in a vacuum. Electrons have mass. There's an upper bound there.
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.
To really get the natural order you're suggesting, you'd have to nuke his mum in the past - requiring faster-than-light-travel - so your troll-biting comment isn't as off-topic as the resulting moderation would imply!
This tagline was transcoded to result in at least one smirk. If you experience failure to smirk, please consult your Gen
What Democrats will do is what they have done all along: Invent all the technology that matters.
Light always travels at the speed of light -- just not always at "speed of light in a vacuum."
Quite true, and sometimes other things can move faster than the speed of light in a medium, but not faster than light travels in a vacuum. Cerenkov radiation, that blue glow seen in the cooling water of some reactors, is emitted by electrons travelling faster than the speed of light in water (but slower than C).
So, does this suggest a reasonable upper temperature for superconductivity?
Is there anything better than clicking through Microsoft ads on Slashdot?
Indiana will simply legislate that all superconductors are performance-invariant.
Problem solved. See how easy that is?
I've fallen off your lawn, and I can't get up.
The Texas school board will simply say that there is no mention of superconductivity in the Bible, therefore it's just a theory that needs to at the least be taught alongside the 'fact' that really an invisible man in the heavens causes electrons to move freely through certain blessed objects. Of course, they'll ignore the fact that there's no mention of electrons or atoms in the book either...
(Warming up to this) Muslims will declare that it's ok to beat conductors, set them on fire, and cut the connectors off them because they aren't superconductors. The conductor only has to be a few years old before you can plug into it. Islam will become the religion of conduction, and young men who wrap themselves with coils of wire that will annihilate them, exploding with great effect when power is applied with the assumption that said coil WAS a superconductor, will go to heaven and be greeted by 77 male virgins named Kelvin. Their first words upon this gruesome discovery will be "Gee had... I only known... Whoops..."
quite. I know I'm being a little bit counter intuitive. but that is just to help me understand better.
so. taking that drift velocity for example.
that v ag = uE doesn't seem to depend on C. and u would appear to be a divide by zero in a superconductor.
The abbreviation for speed of light in a medium is not 'SoL', it's 'v sub g', otherwise known as the group velocity. I would also accept 'C' (capital c), 'c'' (c prime) or 'c sub medium'.
Plausibly the speed of light in a vacuum is not constant, as it is derived from the equation: c**2 = 1/(epsilon sub 0 * mu sub 0), and is thus dependent on the vacuum permitivity and vacuum permeability, which we have little to no experimental evidence of their constancy outside of our local region of space. We also have no evidence that they are not constant, but any small enough gradient integrated over a small enough space is indistinguishable from a constant.
What makes this somewhat less plausible is the extremely high precision with which we are able to measure vacuum permitivity and permeability.