In the Friday 3 September 2004 issue of Science Express, two physicists from Penn State University will announce new experimental evidence for the existence of a new phase of matter, a "supersolid" form of helium-4 with the extraordinary frictionless-flow properties of a superfluid.
"Solid helium-4 appears to behave like a superfluid when it is so cold that the laws of quantum mechanics govern its behavior," says Moses H. W. Chan, Evan Pugh Professor of Physics at Penn State. "One of the most intriguing predictions of the theory of quantum mechanics is the possibility of superfluid behavior in a solid, particularly solid helium-4, and we have strong experimental evidence for this behavior," Chan says.
Chan, and his former student and current postdoctoral associate Eunseong Kim, first announced in the 15 January 2004 issue of the journal Nature their observation of the superfluid-like behavior of solid helium-4, which they had confined in a porous glass with pore diameters of several nanometers. In their current experiment, they observed the same superfluid-like behavior in samples of bulk solid helium without any confining matrix. "Our current experiments with bulk solid helium indicate that the superfluid-like behavior we observed is an intrinsic property of the solid—not the result of confinement in any particular porous medium and not a consequence of the large surface area that accompanies a porous host," Chan explains.
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The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
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