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Jul 17, 2020

“Light Picoscope” – Laser Takes Pictures of Electrons in Crystals

Posted by in categories: chemistry, particle physics

The researchers used powerful laser flashes to irradiate thin, films of crystalline materials. These laser pulses drove crystal electrons into a fast wiggling motion. As the electrons bounced off with the surrounding electrons, they emitted radiation in the extreme ultraviolet part of the spectrum. By analyzing the properties of this radiation, the researchers composed pictures that illustrate how the electron cloud is distributed among atoms in the crystal lattice of solids with a resolution of a few tens of picometers which is a billionth of a millimeter.

The experiments pave the way towards developing a new class of laser-based microscopes that could allow physicists, chemists, and material scientists to peer into the details of the microcosm with unprecedented resolution and to deeply understand and eventually control the chemical and the electronic properties of materials.

For decades scientists have used flashes of laser light to understand the inner workings of the microcosm. Such lasers flashes can now track ultrafast microscopic processes inside solids. Still they cannot spatially resolve electrons, that is, to see how electrons occupy the minute space among atoms in crystals, and how they form the chemical bonds that hold atoms together. The reason is long known. It was discovered by Abbe more than a century back. Visible light can only discern objects commensurable in size to its wavelength which is approximately few hundreds of nanometers. But to see electrons, the microscopes have to increase their magnification power by a few thousand times.

Jul 17, 2020

Scientists achieve major breakthrough in preserving integrity of sound waves

Posted by in categories: energy, engineering, physics

In a breakthrough for physics and engineering, researchers from the Photonics Initiative at the Advanced Science Research Center at The Graduate Center, CUNY (CUNY ASRC) and from Georgia Tech have presented the first demonstration of topological order based on time modulations. This advancement allows the researchers to propagate sound waves along the boundaries of topological metamaterials without the risk of waves traveling backwards or being thwarted by material defects.

The new findings, which appear in the journal Science Advances, will pave the way for cheaper, lighter devices that use less battery power, and which can function in harsh or hazardous environments. Andrea Alù, founding director of the CUNY ASRC Photonics Initiative and Professor of Physics at The Graduate Center, CUNY, and postdoctoral research associate Xiang Ni were authors on the paper, together with Amir Ardabi and Michael Leamy from Georgia Tech.

The field of topology examines properties of an object that are not affected by continuous deformations. In a topological insulator, electrical currents can flow along the object’s boundaries, and this flow is resistant to being interrupted by the object’s imperfections. Recent progress in the field of metamaterials has extended these features to control the propagation of sound and light following similar principles.

Jul 17, 2020

New Amphibious Assault Ship USS Tripoli Joins the U.S. Navy

Posted by in categories: biotech/medical, military

The U.S. Navy welcomed a new amphibious assault ship into the fleet this week even as one of its sister ships lay burning. The ship, designed to deliver Marines by air into hostile territory, was commissioned in a low-key virtual ceremony to ensure social distancing. Tripoli will be based at San Diego Naval Base, California, where sister ship USS Bonhomme Richard is currently on fire.

The ship’s traditional commissioning ceremony, a public event that would have drawn thousands and originally set to take place at Pensacola, Florida, was canceled due to the ongoing COVID-19 pandemic. Instead the ship was commissioned by “administrative message” from the Navy to the fleet, while onboard the crew raised the commissioning flag to signify the event.

Jul 17, 2020

Ground-Breaking Research Shows That Laser Spectral Linewidth Is Classical-Physics Phenomenon

Posted by in category: quantum physics

New ground-breaking research from the University of Surrey could change the way scientists understand and describe lasers – establishing a new relationship between classical and quantum physics.

In a comprehensive study published by the journal Progress in Quantum Electronics, a researcher from Surrey, in partnership with a colleague from Karlsruhe Institute of Technology and Fraunhofer IOSB in Germany, calls into question 60 years of orthodoxy surrounding the principles of lasers and the laser spectral linewidth – the foundation for controlling and measuring wavelengths of light.

In the new study, the researchers find that a fundamental principle of lasers, that the amplification of light compensates for the losses of the laser, is only an approximation. The team quantify and explain that a tiny excess loss, which is not balanced by the amplified light but by normal luminescence inside the laser, provides the answer to the spectral linewidth of the laser.

Jul 17, 2020

China Mars Mission: At the Launch Pad (Updated with Video, Photos)

Posted by in category: space

The fourth Long March-5 rocket, to be used to launch China’s first Mars exploration mission — the Tianwen-1 — was vertically transported to the launching area at the Wenchang Space Launch Center in south China’s Hainan Province on Friday.

Jul 17, 2020

Researchers discover 2 paths of aging and new insights on promoting healthspan

Posted by in categories: bioengineering, biotech/medical, genetics, life extension

Aging/longevity link!


Molecular biologists and bioengineers at the University of California San Diego have unraveled key mechanisms behind the mysteries of aging. They isolated two distinct paths that cells travel during aging and engineered a new way to genetically program these processes to extend lifespan.

The research is described July 17 in the journal Science.

Continue reading “Researchers discover 2 paths of aging and new insights on promoting healthspan” »

Jul 17, 2020

How the Brain Builds a Sense of Self From the People Around Us

Posted by in categories: mobile phones, neuroscience

We are highly sensitive to people around us. As infants, we observe our parents and teachers, and from them we learn how to walk, talk, read—and use smartphones. There seems to be no limit to the complexity of behavior we can acquire from observational learning.

But social influence goes deeper than that. We don’t just copy the behavior of people around us. We also copy their minds. As we grow older, we learn what other people think, feel, and want—and adapt to it. Our brains are really good at this—we copy computations inside the brains of others. But how does the brain distinguish between thoughts about your own mind and thoughts about the minds of others? Our new study, published in Nature Communications, brings us closer to an answer.

Our ability to copy the minds of others is hugely important. When this process goes wrong, it can contribute to various mental health problems. You might become unable to empathize with someone, or, at the other extreme, you might be so susceptible to other people’s thoughts that your own sense of “self” is volatile and fragile.

Jul 17, 2020

NASA plans to return its astronauts in SpaceX’s Crew Dragon spacecraft on Aug. 2

Posted by in category: alien life

NASA is currently planning to return astronauts Bob Behnken and Doug Hurley to Earth on board SpaceX’s Crew Dragon spacecraft in about two weeks, the space agency told CNBC on Friday.

The spacecraft, which the astronauts named Endeavour, is scheduled to splash down in the Atlantic Ocean on Aug. 2 at about 3 p.m. ET, according to NASA’s Johnson Space Center public affairs officer Kyle Herring.

Herring noted that the departure time from the International Space Station “is a bit of a moving target,” but said in an email that the spacecraft is scheduled to un-dock at about 8 p.m. ET on Aug. 1. NASA will look more closely at the weather forecasts for where the spacecraft might splash down after the astronauts perform a spacewalk next week. NASA Administrator Jim Bridenstine also confirmed those dates.

Jul 17, 2020

NVIDIA Faces a Tough New Rival in Artificial Intelligence Chips

Posted by in category: robotics/AI

Graphcore is offering a cheaper and more streamlined approach to AI tasks.

Jul 17, 2020

New cobalt-free lithium-ion battery reduces costs without sacrificing performance

Posted by in category: energy

Researchers at the University of Texas at Austin have demonstrated a cobalt-free, high-energy, lithium-ion battery.