Lifeboat Foundation

One of the greatest obstacles to producing energy via fusion on Eearth is the formation and growth of small magnetic field imperfections in the core of experimental fusion reactors. These reactors, called tokamaks, confine hot ionized gas, or plasma. If the imperfections persist, they let the energy stored in the confined plasma leak out; if allowed to grow, they can lead to sudden termination of the plasma discharge. Recent simulations of tokamak discharges with fast, energetic ions have shown that the structure of the magnetic field can either stabilize or destabilize these magnetic imperfections, or “tearing” instabilities. The result depends on the helical structure of the field as it winds around the tokamak.

Energetic ions, ubiquitous in fusion plasmas, can be a strong stabilizing or destabilizing force. The choice depends on the magnetic shear in the plasma. Understanding the physics driving the onset of the instabilities can lead to their avoidance, a “zero tolerance” approach, vital for ITER’s stable operation. ITER is a key step between today’s fusion research and tomorrow’s fusion power plants. Also, the results explain many experimental observations of tearing instabilities that limit the maximum heat energy that can be contained.

Advanced tokamaks achieve high-thermal-energy plasmas by injecting beams of hot ions that collide with, and thereby heat, the background plasma. Burning plasma experiments that create energy from fusion reactions, such as ITER, will also have a significant population of hot alpha particles, the byproduct of fusion. The effects that energetic ions have on the benign instabilities, such as the sawtooth instability, which causes the temperature near the plasma core to flatten, and the toroidal Alfvén eigenmode, which intuitively is a “vibration” (wobble) of the magnetic field lines, have been known for some time.

Continue reading “Eliminating small instabilities in tokamaks before they become disruptions” »

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 time crystals 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.

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.

Continue reading “A new physics discovery could change the game for quantum computing” »

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 particles not only as the redox reactant in hydrogen production, 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 hydrogen production. Using mirrors reflecting focused sunlight onto a receiver, CST can generate very high temperatures for thermochemical processes in a solar reactor, up to 2,000°C, and can store solar energy thermally so it can dispatch the energy when needed.

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.

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.

Continue reading “Scientists Discover How to Harness the Power of Quantum Spookiness” »

A conglomerate of ultracold atoms reproduces some of the physics of the early universe.

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.

Continue reading “Artificial intelligence accelerates discovery of metallic glass” »

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.

Continue reading “‘Interplanetary Shock Wave’ Spawns Electric-Blue Auroras” »