Invisible ‘Demon’ Discovered in Odd Superconductor

In 1956, David Pines formulated a phantom. He predicted the existence of seas of electric ripples that could neutralize each other, rendering the overall ocean motionless even as individual waves ebbed and flowed. The oddity, which came to be known as Pines’ demon, would be electrically neutral, and therefore invisible to light — the definition of tough to detect. Over the decades…

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