Are you down with Helium, Solid!

Can Helium-4 Transition to a Supersolid? from PhysOrg.com

For forty years supersolid behavior has been predicted, and since the 1970s, theories about supersolid behavior involving helium-4 have been developed. However, it wasn’t until 2004 that some evidence of supersolid behavior was found. But, when a group of scientists from the Helsinki University of Technology tested the thermodynamical properties of solid helium-4, they found something different.

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