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Yale physicists have uncovered hints of a time crystal—a form of matter that “ticks” when exposed to an electromagnetic pulse—in the last place they expected: a crystal you might find in a child’s toy.

The discovery means there are now new puzzles to solve, in terms of how form in the first place.

Ordinary crystals such as salt or quartz are examples of three-dimensional, ordered spatial crystals. Their atoms are arranged in a repeating system, something scientists have known for a century.

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From tunneling through impenetrable barriers to being in two places at the same time, the quantum world of atoms and particles is famously bizarre. Yet the strange properties of quantum mechanics are not mathematical quirks—they are real effects that have been seen in laboratories over and over.

One of the most iconic features of quantum mechanics is “entanglement”—describing particles that are mysteriously linked regardless of how far away from each other they are. Now three independent European research groups have managed to entangle not just a pair of particles, but separated clouds of thousands of atoms. They’ve also found a way to harness their technological potential.

When particles are entangled they share properties in a way that makes them dependent on each other, even when they are separated by large distances. Einstein famously called entanglement “spooky action at a distance,” as altering one particle in an entangled pair affects its twin instantaneously—no matter how far away it is.

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Researchers have built a new dynamic model showing how hydrogen produced with concentrated solar thermal energy can be made more continuously through a novel seasonal control strategy with ceria (CeO2) particles buffering the effect of variation in solar radiation.

A paper, “Dynamic Model of a Continuous Hydrogen Production Plant Based on CeO2 Thermochemical Cycle,” presented at the SolarPACES2017 Annual Conference, proposes using ceria not only as the redox reactant in , but also for heat storage and heat transfer media (or medium) to control the temperatures.

Hydrogen can be produced by splitting water (H2O into H2 and oxygen) at very high temperatures using concentrated solar thermal (CST) — avoiding today’s use of fossil fuels for production. Using mirrors reflecting focused sunlight onto a receiver, CST can generate very high temperatures for thermochemical processes in a solar , up to 2,000°C, and can store solar energy thermally so it can dispatch the energy when needed.

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Four lasers beam out from one of the Unit Telescopes of ESO’s Very Large Telescope (VLT), guiding your eyes to the Small and Large Magellanic Clouds beneath them.

The Four Laser Guide Star Facility (4LGSF) shines four 22-watt laser beams into the sky to create artificial guide stars by making sodium atoms in the upper atmosphere glow so that they look just like real stars. The artificial stars allow the adaptive optics systems to compensate for the blurring caused by the Earth’s atmosphere and so that the telescope can create sharp images.

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From tunneling through impenetrable barriers to being in two places at the same time, the quantum world of atoms and particles is famously bizarre. Yet the strange properties of quantum mechanics are not mathematical quirks—they are real effects that have been seen in laboratories over and over.

One of the most iconic features of quantum mechanics is “entanglement”—describing particles that are mysteriously linked regardless of how far away from each other they are. Now three independent European research groups have managed to entangle not just a pair of particles, but separated clouds of thousands of atoms. They’ve also found a way to harness their technological potential.

When particles are entangled they share properties in a way that makes them dependent on each other, even when they are separated by large distances. Einstein famously called entanglement “spooky action at a distance,” as altering one particle in an entangled pair affects its twin instantaneously—no matter how far away it is.

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If you combine two or three metals together, you will get an alloy that usually looks and acts like a metal, with its atoms arranged in rigid geometric patterns.

But once in a while, under just the right conditions, you get something entirely new: a futuristic alloy called metallic glass. The amorphous material’s atoms are arranged every which way, much like the atoms of the glass in a window. Its glassy nature makes it stronger and lighter than today’s best steel, and it stands up better to corrosion and wear.

Although metallic glass shows a lot of promise as a protective coating and alternative to steel, only a few thousand of the millions of possible combinations of ingredients have been evaluated over the past 50 years, and only a handful developed to the point that they may become useful.

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A moderate geomagnetic storm kicked up in Earth’s skies Friday morning (April 20), bringing green and rare electric-blue auroras that stretched as far south as Indiana.

The space-weather news site Spaceweather.com reported that an “interplanetary shock wave” hit Earth’s magnetic field at about 3:50 a.m. EDT (2350 on April 19 GMT), quadrupling the intensity of the flow of particles streaming from the sun toward Earth, called the solar wind. The incoming wave of material resulted in a G2-level, or moderate, geomagnetic storm, according to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC). These types of storms can cause power grid fluctuations and have some impact on radio communications. [See Spectacular Photos of Auroras from Space]

And they also cause enhanced auroras. This storm led to auroras possibly reaching through Canada and as far south as New York, Wisconsin and Washington state in the U.S., the SWPC said.

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Eerie similarities unite vastly different scientific ideas in sometimes utterly surprising ways. One of these similarities may have allowed scientists to recreate the expanding universe—on a countertop.

Researchers accomplished their feat using Bose-Einstein condensates, which are collections of certain atoms held to the near coldest-possible temperatures. Bose-Einstein condensates let scientists see teeny quantum mechanical effects on a much larger scale, and have been used to do lots and lots of wild physics. These scientists hope they can use its quirks to model the behavior of the far grander cosmos.

“It’s hard to test theories of cosmology,” study author Gretchen Campbell, from the University of Maryland’s Joint Quantum Institute, told Gizmodo. “Maybe we can actually find a way to study some cosmological models on the laboratory scale.”

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A team of researchers from the National Institute of Informatics (NII) in Tokyo and NTT Basic Research Laboratories (BRL, Nippon Telegraph and Telephone Corporation) in Japan have published an explanation of how quantum systems may be able to heat up by cooling down. Their paper appeared recently in Physical Review Letters.

“Heating by cooling sounds rather counterintuitive, but if the system has symmetries, decay could mean many things,” says Kae Nemoto, a professor in the Principles of Informatics Research Division at NII which is part of the Inter-University Research Institute Corporation Research Organization of Information and Systems (ROIS).

Nemoto and her team examined a double sub– system coupled to a single constant temperature reservoir. Each sub-domain contained multiple spins—a form of angular momentum carried by elementary particles such as electrons and nuclei. The researchers considered the situation in which the spins within each sub-domain are aligned with respect to each other, but the sub-domains themselves are oppositely aligned (for instance all up in one and all down in the second). This creates a certain symmetry in the system.

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