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    Quantum jitter lets heat travel across a vacuum

    For the first time, scientists have measured the heat transferred by the quantum effervescence of empty space. Two tiny, vibrating membranes reached the same temperature despite being separated by a vacuum, physicists report in the Dec. 12 Nature. The result is the first experimental demonstration of a predicted but elusive type of heat transfer. Normally, […] More

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    A new, theoretical type of time crystal could run without outside help

    A newly proposed type of time crystal could stand alone. Time crystals are structures that repeat regularly in time, just as a standard crystal is composed of atoms arranged in a regularly repeating pattern in space. Scientists first created time crystals in 2016 (SN: 10/26/16). But those crystals require periodic blasts from a laser to […] More

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    Lead becomes stronger than steel under extreme pressures

    Lead performs under pressure. Under normal conditions, the metal is relatively soft, easily scratched with a fingernail. But when compressed under extreme pressures, lead becomes hard and strong — even stronger than steel, scientists report November 11 in Physical Review Letters. To study how lead’s strength changed under pressure, researchers rapidly compressed a lead sample […] More

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    The first artificial material that follows sunlight may upgrade solar panels

    As the sun moves across the sky, sunflowers continually orient themselves to soak up the most light (SN: 8/4/16). Now a type of human-made material can do that, too. This is the first artificial material capable of phototropism, researchers report November 4 in Nature Nanotechnology. Stemlike cylinders of the material, dubbed SunBOTs, maneuvered to capture […] More

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    Molecular jiggling may explain why some solids shrink when heated

    When things heat up, most solids expand as higher temperatures cause atoms to vibrate more dramatically, necessitating more space. But some solid crystals, like scandium fluoride, shrink when heated — a phenomenon called negative thermal expansion. Now, by measuring distances between atoms in scandium fluoride crystals, scientists think that they have figured out how that […] More

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    Google officially lays claim to quantum supremacy

    Quantum supremacy is here, researchers from Google claim. For the first time, a quantum computer has solved a problem that can’t be performed by a standard computer — at least not within a reasonable amount of time — Google announced October 23. This milestone, known as quantum supremacy, is a long-anticipated step toward useful quantum […] More

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    Physicists have found quasiparticles that mimic hypothetical dark matter axions

    An elusive hypothetical particle comes in imitation form. Lurking within a solid crystal is a phenomenon that is mathematically similar to proposed subatomic particles called axions, physicist Johannes Gooth and colleagues report online October 7 in Nature. If axions exist as fundamental particles, they could constitute a hidden form of matter in the cosmos, dark […] More

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    A new cooling technique relies on untwisting coiled fibers

    A new way to chill out is simple: Just unwind. Called twistocaloric cooling, the method involves unwinding tightly twisted strands of various materials. The technique was used to chill water by several degrees Celsius, scientists report in the Oct. 11 Science. Cooling techniques like those used in traditional refrigerators rely on cycles of compressing and […] More