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Scientists Create Supersolid From Helium
jabberjaw writes "Nature is reporting that Pennsylvania State University researchers Eun-Seong Kim and Moses Chan have created a 'supersolid' from helium-4. Although a crystalline solid, the supersolid can flow much like a liquid. This is due to the fact that the empty compartments in the crystal move coherently, thus waves can progress through the lattice. The supersolid state can be compared to the superfluid state. Perhaps a condensed matter physicist can dumb the article down for layfolk such as myself?"
Joyous helium
Becomes a supersolid
At low Celcius
But seriously, this stuff is really cool. What with the properties they described, I wonder if it could be useful in conducting electricity or forming a shock-absorbing barrier?
Cyde Weys Musings - Scrutinizing the inscrutable
My dad did his PhD thesis on liquid helium 3. Apparently it's pretty difficult to contain the stuff, since even the tiniest opening in a container is enough for everything to escape at once (no viscosity)...
Also, since it is inflammable
I think you mean nonflammable. Inflammable is the same as flammable.
Liquid hydrogen and liquid peroxide certainly aren't flammable. In fact, water at room temperature is more flammable than liquid hydrogen. It's all a matter of temperature: something at hundreds of degrees below zero certainly isn't going to burn. You're right, if the hydrogen heated up and turned gaseous, then it would be flammable ... but then it also wouldn't still be liquid hydrogen.
Not that this really matters, because who would use liquid hydrogen as a coolant, when liquid nitrogen is so much better?!
Cyde Weys Musings - Scrutinizing the inscrutable
I heard about something like this a few years back, as I understood it then the thing is that at low enough temperatures atoms break down into a "soup" of protons, neutrons and electrons all behaving like a liquid.
It was a (Swedish) magazine article, so no links I'm afraid. Is this the same thing or entierly different?
.: Max Romantschuk
A superfluid is a fluid that flows without viscosity, meaning that if you were to stir a spoon in a superfluid soup, you could take out the spoon and the soup would keep swirling forever on, since there is no mechanism there (i. e. no friction) to make the vortex you just made disappear. Now if you were to cool a 4He crystal, there would be eventually be no more movement of atoms and the whole thing froze out. But in quantum mechanics, there is the Heisenberg uncertainty Principle which basically states that you are not to now the position of any particle along with its velocity with the same accuracy. There will always be a trade off. The better you know the position, the worse you know the velocity. This accounts for the fact that even at absolute zero, there are some fluctuations of particles, called quantum fluctuations wich do never freeze out. When a superfluid appears this means that the atoms in it move all together. As the Nature article suggests, you can compare this to soldiers on a parade. They all move alike. In a supersolid then, you have vacancies, places where atoms are absent. Think of holes in a semiconductor if you like. There, holes are just non-electrons. Here we deal with non-atoms, and they are the ones behaving like soldiers in the case of a supersolid. Meaning the propagate through the whole thing as if they were on a parade, which makes them great for sending any wave (electromagnetic or other) through the crystal, and since these vacancies move in order, they propagate the wave without damping it. This would make a hell of an amplifier. Compare the situation to a superconductor, where you can propagate electric current without damping (i. e. having no resistance at all). To electric current, a superconductor behaves like a supersolid to waves of any kind.
Black holes were created when god tried to divide by zero
In actuality, superfluids do NOT have zero viscosity at all points. They have very complex properties, depending on a combination of the container, exact conditions, etc, etc. Typically, some parts of superfluids exhibit zero viscosity (truly zero), leading to some fascinating fluid mechanics. For example, the Stokes singular problem actually has NO boundary layer, so drag goes to zero. There are plenty of other really interesting phenomenon - some that might be utilized in future technology.
Other interesting properties of superfluids include rather odd magnetic fields (Helium-3 or 4 is odd to start with, and then chilling it down and spinning it does some interesting stuff), VERY odd conduction, etc, etc. I imagine that there will be future Nobel prizes given out for research in this area (I believe one already has been, a few years back). Studying how superfluids act can give us some very interesting insights into what actually happens in various media at tiny sizes. One example would be looking at fluid/solid interfaces, and trying to determine what precisely goes on there. The possibilities are endless...
That being said, isn't the official definition of a fluid "something that deforms continuously under shear stress"? As such, does this indicate that these supersolids do NOT flow continuously?
"Don't bother me with that pocket calculator stuff" - Deep Thought
"Perhaps a condensed matter physicist can dumb the article down for layfolk such as myself?"
Imagine a big block of swiss cheese (the kind of cheese that's got all the holes in it). Now those holes are basically "vacancies" of cheese. Now, imagine if the holes moved around.
Similarly, think of one of those pictures underwater videos of SCUBA divers... You know when they release a breath, and all the bubbles start moving up to the surface of the water... Those are likes 'holes' in the water. More specifically, they are "vacancies" and they move in a somewhat orderly manner (up). Of course, it makes more common sense that vacancies would move around in a liquid than in solids....
So, basically, they've found a state of matter where the vacancies move around in a solid. In a sense, they're claiming that they found a block of cheese in the refridgerator where the holes keep moving. And this is why there's going to be controversy over this claim: they're alot of people who are going to say "no way - cheese doesn't work that way..."
It would make for a crazy club sandwich... Yum.
FYI: I'm not a condenced matter physicist, although I do happen to have a degree in the History and Philosophy of Science...
I helped move some furniture from the 1880s that included some thick mirrors. There was noticeable distortion at the bottom of the mirrors that wasn't perceptable, if present, at the top. The bottom of the mirrors looked wavy.
I can say for sure, but it looked like the glass had flowed in only 100 years or so. Maybe glass technology has changed. Maybe I misunderstood what was happening.
Why do I have this? I don't smoke.
There is a cool thermal acoustic refrigeration technique that employs hemholtz principals described in American Scientist a few moons ago. There is also a means of using a Hemholtz filter to create a kind of check valve (I have to look for that reference... if you need it ask) hence providing a "one-way" flow.
Water is already an oxide. In fact it is an oxide of hydrogen. So I doubt water being more flammable than even liquid hydrogen.
it would take billions of years before there would be a measurable change in thickness.
So what you're saying is that they actually do flow. In reality they flow faster than "billions of years", but either way, it's a liquid.
Karma: It's all a bunch of tree-huggin' hippy crap!
One of the big problems our power grid has is that electricity must be generated based on demand. There's no way to store electricity for use later during peak hours.
However, a fluid or solid that "once stirred would continue swirling forever" sounds like an interesting possibility for a storage device. Imagine causing the fluid to begin spinning at a high rate using electromagnetic fields. Then, at some later time (i.e., peak demand periods), converting the kinetic energy of the fluid back into electricity. In a sense, it's a frictionless gyro that acts as a kinetic battery.
The not entirely unrelated science of Nuclear Magnetic Resonance Imaging found its way into medical imaging devices, leading to early detection and cure of many cancers.
Its possible that this technology could end up in some very sensitive detectors (see previous threads for the possiblility of perfect amplifiers) that allow Doctors to view biochemical processes as they happen in a living organism. This would lead to a complete revolution in medicine, understanding protein folding, alzheimers, MS, etc would happen almost overnight.
**TODO** Steal someone elses sig.
Although supersolid He4 does not seem like a solid, by some definitions it is. At any given instant, the atoms in the material appear to be in a crystalline lattice (not bouncing around like the atoms in a liquid). But if you exert any force on that supersolid, the vacancies and defects in the lattice instantly shift to let the solid move. This gives the "solid" a shear strength of zero even if the atoms seem like they are arranged in what appears to be a rigid crystal structure.
The problem with commonsense notions of "solid" vs. "liquid" is that they don't reflect all the possible states of matter, only the ones that occur at room temperatures. Science usually finds these counterintuitive phenomena outside the usual conditions of everyday life (like when physicists proved that Newton's centuries old laws only work for "slow" speeds, so we need Eistein's equations to understand higher speeds).
Two wrongs don't make a right, but three lefts do.
Maybe that nice reporter lady who told us all about the weight of clouds in terms of elephants could have a go at dumbing it down for us?
"If it's lost, it'll turn up. Things always do" "I love it when a plan comes together"
But I've seen cathedral windows that weren't just a different thickness at the bottom, they were sagging open at the top!
On the other hand, as one of the links points out, you can disprove the theory by simple mathematics.
Cathedral window age = 500 years
Cathedral window sag = 1 cm
Theoretical sag rate = 500 years/cm
Egyptian/Greek/Whatever glass vessel age = 3000 years
Theoretical sag rate = 500 years/cm
Expected sag of 300 year old glass = 6 cm
As the link notes, if glass flowed over time, all the old glassware in museums would show definite signs of puddling -- even taking into account differences in formulae. At the very least, the broken edges would have smoothed themselves like ripped-apart Silly Putty.
I wasn't convinced until I read the link. I had completely bought into the sagging glass idea!
Here's an alternate theory for the cathedral glass. When the window was made, using old-school techniques, they ended up with some imperfect pieces. Do you put those at the bottom, where the bishop will see them... or put them at the top, and let God decide if He cares?
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
There are MANY more states of matter than solid, liquid, and gas. There's plasma, 2-dimensional fluids, 1-dimensional crystals, ambiplasma of partcies and antiparticles, photon crystals, and lots of others.
I thought the states of matter were a function of temperature (energy level). From that I've come up with my list of states of matter:
1. Super-solid: includes BEC (Bose-Einstein Condensate), this new discovery, neutron star stuff, etc.
2. Solid
3. Liquid
4. Gas
5. Plasma - ionized gas; too hot for electrons to remain around nucleii
6. Electroweak - matter above the energy state at which electromagnetic and weak nuclear forces unify
7. Electrostrong - matter above the energy state at which electromagnetic, weak and strong nuclear forces unify.
8. GUT matter - above the energy state at which all forces are unified.
I believe that state 6 and maybe (???) state 7 is achievable in a particle accelerator. State 8 only exists early in the universe, maybe before the plank time?
The other "states" you mentioned would see to me to be more analogous to fractal (or partial) dimensions and not directly considered states.
Just my 2 cents.
I'm not a journalist, but I play one on slashdot