quantum mechanics has done it again in an experiment with supercooled helium researchers at penn state say they have found that as a solid ring spins around part of it can remain perfectly still at ultracold temperatures matter often behaves far differently than it does in everyday experience for instance many materials turn into superconductors able to conduct electricity with no resistance because electrons coalesce and move in synchrony without hitting the surrounding lattice of atoms in a similar way other materials at low temperatures become superfluids which flow without viscosity to slow them down the new experiment suggests a new state of matter: a supersolid in the 1970s physicists played with the notion that a solid – a material whose atoms generally stack together in a neat crystal pattern – might also undergo a quantum transformation some suggested that when sufficiently chilled some of the atoms in a solid would melt into a superfluid and effortlessly flow through the surrounding solid they called this state a supersolid most physicists including some who had suggested the idea concluded that although this state was possible it was unlikely to be observed i have written at least one paper in the remote past about the possibility of supersolid behavior said dr anthony j leggett a professor of physics at the university of illinois who was awarded the nobel prize in physics last year for theoretical work on superfluids i would have bet at least 100 to 1 against it in an article published this month on the web site of the journal science dr moses h w chan a professor of physics at penn state and dr eunseong kim a postdoctoral researcher reported that they had turned helium into a supersolid the theorists will be surprised dr chan said but they do not exclude such a possibility helium the same gas that levitates blimps and gives a person donald ducks voice turns into a liquid at minus-452 degrees fahrenheit chilled slightly further and squeezed under immense pressure helium atoms are pushed together into a solid in the experiment dr chan and dr kim placed solid helium in a small ring cooled it to almost absolute zero and exerted pressures ranging from 380 pounds per square inch to 970 pounds per square inch the usual atmospheric pressure on the earths surface is 147 pounds per square inch the ring attached to a rod was then twisted and released the twisting force in the rod caused the ring to oscillate at a steady frequency determined by the mass and size of the ring as the temperature was cooled below minus-45922 degrees – half a degree above absolute zero – the frequency of oscillations sped up as if the ring were losing mass until it appeared that 15 percent of the helium had vanished the penn state scientists believe that 15 percent of the solid helium had turned into a superfluid and according to the rules of the quantum mechanics fell into the laziest possible energy state: motionless as the solid ring oscillated back and forth the superfluid flowed in the opposite direction in such a way that it appeared to remain exactly still to check that some of the helium had not actually escaped the scientists warmed the ring back up and the oscillations slowed again they repeated the experiment with a lighter version of helium helium-3 which is known not to change into a superfluid and they found no shift in the oscillation frequency so far other physicists agree the supersolid explanation makes the most sense but they would like to see more data i think everybody agrees we need more said dr wayne saslow a professor of physics at texas a&m university its calling out for more experiments how a superfluid could flow through a solid defies ready explanation i think its a major puzzle dr leggett said if this stands up then its going to make us totally rethink our concept of what a quantum solid is one possibility dr leggett said is that the helium solid is not perfect that a few locations in the helium crystal lattice are empty and the superfluid is flowing from one empty location to another but higher pressures which presumably would push atoms to fill the empty locations did not diminish the supersolid effect another possibility is that helium atoms momentarily double up at a lattice site before one of the occupants is pushed out to another site three decades ago dr saslow read dr leggetts paper describing how a supersolid might behave and wrote computer programs to explore the idea in more depth before moving on to other research i thought i would never see it again dr saslow said its like it came from the dead when he heard of the penn state work several months ago dr saslow searched for his old computer programs he thought they were lost until he opened a file folder containing printouts of the programs in quantum mechanics a helium atom is not a discrete object but a fuzzy blur of possibilities dr saslow said the superfluid could be thought of as the flow of fuzziness between the atoms nothing here makes sense he admitted the programs which produce much more precise answers today running on his laptop than was possible on a 1970s-era mainframe computer predict a superfluid fraction of 2 percent roughly in agreement with the penn state results the post only in quantum physics: spinning while standing still appeared first on texas a&m college of science