It may sound like science fiction, but it’s not: Scientists have created the first time crystal, using a chain of ions. Just as a standard crystal repeats in a regular spatial pattern, a time crystal repeats in time, returning to a similar configuration at regular intervals.
If scientists had sacred objects, this would be one of them: a single, closely guarded 137-year-old cylinder of metal, housed in a vault outside of Paris. It is a prototype that precisely defines a kilogram of mass everywhere in the universe.
Washington - A quantum internet could one day allow ultrasecure communication worldwide - but first, scientists must learn to tame unruly quantum particles such as electrons and photons. Several new developments in quantum technology, discussed at a recent meeting, have brought scientists closer to such mastery.
The black holes that produced the first detected gravitational waves may have exotic origins in the early universe. When the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, glimpsed gravitational waves from two merging black holes, scientists were surprised at how large the black holes were - about 30 times the mass of the sun.
In a few highly specialized laboratories, scientists bombard matter with the world’s most powerful electrical pulses or zap it with sophisticated lasers. Other labs squeeze heavy-duty diamonds together hard enough to crack them. All this is in pursuit of a priceless metal. It’s not gold, silver or platinum. The scientists’ quarry is hydrogen in its most elusive of forms.
Falling down a hole through the center of the Earth would be rough - especially if there’s friction. A new study reveals what would happen to an intrepid traveler who jumped into a hypothetical tunnel through Earth, propelled by the force of gravity but impeded by air resistance and the friction of the tunnel walls. Physicists have estimated that if you jumped into a tunnel without such forms of drag, you would reach the other side in less than an hour.
A puzzling mismatch is plaguing two methods for measuring how fast the universe is expanding. When the discrepancy arose a few years ago, scientists suspected it would fade away, a symptom of measurement errors. But the latest, more precise measurements of the expansion rate - a number known as the Hubble constant - have only deepened the mystery.
Harnessing the weirdness of the quantum world is difficult - fragile quantum properties quickly degrade under typical conditions. But such fragility could help migrating birds find their way. Some scientists think birds navigate with quantum-mechanical compasses, and the new study suggests quantum fragility would enhance birds’ sense of direction.