Lifeboat Foundation

To calculate the most stable atomic configuration, as well as estimate its hardness, the team relied on a computational method called density functional theory (DFT). DFT has been successfully used throughout chemistry and solid-state physics to predict the structure and properties of materials. Keeping track of the quantum states of all the electrons in a sample, and their interactions, is usually an intractable task. Instead, DFT uses an approximation that focuses on the final density of electrons in space orbiting the atoms. This simplifies the calculation to make it suitable for computers, while still providing very precise results.

Based on these calculations, the scientists found that the Young’s modulus, a measure of hardness, for pentadiamond is predicted to be almost 1700 GPa – compared with about 1200 GPa for conventional diamond.

“Not only is pentadiamond harder than conventional diamond, its density is much lower, equal to that of graphite,” explains co-author Professor Mina Maruyama.

Linus Torvalds, the creator of Linux, offered up some interesting thoughts on Intel’s Advanced Vector Extensions 512 (AVX-512) instruction set, calling it a “power virus” that was only created to make the company’s CPU hardware perform well in benchmarks. He also admitted to being “biased” and “grumpy” in his assessment.

His comments came in a mailing list (via Phoronix) discussing an article suggesting AVX-512 might not be part of Intel’s upcoming Alder Lake architecture. If that comes to pass, it will be just fine by Torvalds.

AMD is bringing its acclaimed Ryzen Threadripper processor lineup to the workstation PC market, starting with a new Lenovo ThinkStation model that can be equipped with 64 processor cores.

The new Ryzen Threadripper Pro chips, unveiled on Tuesday, will mark the first time in three years that workstation customers can look to AMD as an alternative to Intel’s Xeon CPUs. The current Xeon W offerings for workstations max out at 28 cores, while the new flagship Threadripper Pro 3995WX has 64 cores and 128 processor threads, which AMD says is the highest number of cores and threads available in a workstation PC.

The ThinkStation P620, the first PC to offer the new Threadripper Pro, will start shipping to customers in September for a starting price of $4,599. When equipped with the 64-core chip, it will offer better performance for some processing tasks—including rendering a 3D image with Maxon’s Cinebench R20 app—than a workstation equipped with two of the 28-core Xeon W chips, AMD says.

New research, based on earlier results in mice, suggests that our brains are never at rest, even when we are not learning anything about the world around us.

Our brains are often likened to computers, with learned skills and memories stored in the activity patterns of billions of nerve cells. However, new research shows that memories of specific events and experiences may never settle down. Instead, the activity patterns that store information can continually change, even when we are not learning anything new.

Why does this not cause the brain to forget what it has learned? The study, from the University of Cambridge, Harvard Medical School and Stanford University, reveals how the brain can reliably access stored information despite drastic changes in the brain signals that represent it.

MIT engineers develop a hybrid process that connects photonics with “artificial atoms,” to produce the largest quantum chip of its type.

MIT researchers have developed a process to manufacture and integrate “artificial atoms,” created by atomic-scale defects in microscopically thin slices of diamond, with photonic circuitry, producing the largest quantum chip of its type.

The accomplishment “marks a turning point” in the field of scalable quantum processors, says Dirk Englund, an associate professor in MIT’s Department of Electrical Engineering and Computer Science. Millions of quantum processors will be needed to build quantum computers, and the new research demonstrates a viable way to scale up processor production, he and his colleagues note.

Further improvements in nuclear propulsion system efficiency beyond nuclear-electric (NEP) are possible. The fission process accelerates the fission fragments to velocities between 3–5% of the speed of light, far faster than the 0.027% achieved by NEP, which uses a conventional nuclear reactor to convert the kinetic energy of the fission fragments into heat, the heat into electricity, and the electricity back into Xe ion kinetic energy with eficiencies much less than 40%. In the fission fragment reactor, the high-speed fragments are used directly as the rocket exhaust after charge neutralization. Therefore the fission fragment rocket can produce a specific impulse (Isp) greater than one million seconds.[CR][CR]Previous concepts suRered from impractical or inadequate methods to cool the fission fuel. In this work the heating problem is overcome by dividing the solid fuel into small dust particles and thereby increasing the surface to volume ratio of the fuel. The small size of the fuel particle allows adequate cooling to occur by the emission of thermal radiation.

July 13, 2020—Researchers at Columbia Engineering and Montana State University report today that they have found that placing sufficient strain in a 2-D material—tungsten diselenide (WSe2)—creates localized states that can yield single-photon emitters. Using sophisticated optical microscopy techniques developed at Columbia over the past three years, the team was able to directly image these states for the first time, revealing that even at room temperature they are highly tunable and act as quantum dots, tightly confined pieces of semiconductors that emit light.

“Our discovery is very exciting, because it means we can now position a single-photon emitter wherever we want, and tune its properties, such as the color of the emitted photon, simply by bending or straining the material at a specific location,” says James Schuck, associate professor of mechanical engineering, who co-led the study published today by Nature Nanotechnology. “Knowing just where and how to tune the single-photon emitter is essential to creating quantum optical circuitry for use in quantum computers, or even in so-called ‘quantum’ simulators that mimic physical phenomena far too complex to model with today’s computers.”

Developing quantum technologies such as quantum computers and quantum sensors is a rapidly developing field of research as researchers figure out how to use the unique properties of quantum physics to create devices that can be much more efficient, faster, and more sensitive than existing technologies. For instance, quantum information—think encrypted messages—would be much more secure.

But, he added, the method took about 10 minutes to produce 1,024 random strings, whereas current cryptographic processes would need far faster number generators.

The new technique’s first real-world use will come when it’s incorporated into NIST’s randomness beacon, a public source of randomness for researchers studying unpredictability, Bierhorst said.

But he added that he hopes the experimental setup could one day be shrunk enough to fit on a computer chip and help in the creation of “unhackable” messages.

Researchers at ETH have measured the timing of single writing events in a novel magnetic memory device with a resolution of less than 100 picoseconds. Their results are relevant for the next generation of main memories based on magnetism.

At the Department for Materials of the ETH in Zurich, Pietro Gambardella and his collaborators investigate tomorrow’s memory devices. They should be fast, retain data reliably for a long time and also be cheap. So-called magnetic “random access memories” (MRAM) achieve this quadrature of the circle by combining fast switching via electric currents with durable data storage in magnetic materials. A few years ago researchers could already show that a certain physical effect – the spin-orbit torque – makes particularly fast data storage possible. Now Gambardella’s group, together with the R&D-center IMEC in Belgium, managed to temporally resolve the exact dynamics of a single such storage event – and to use a few tricks to make it even faster.

Magnetizing with single spins.