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Dec 15, 2020

Rocket startup Astra reaches space for the first time with second launch attempt from Alaska

Posted by in category: space

San Francisco-area startup Astra became the latest U.S. rocket builder to reach space on Tuesday, with the successful launch of its Rocket 3.2 vehicle from Kodiak, Alaska.

The rocket came just shy of reaching orbit, with Astra CEO Chris Kemp telling reporters after the launch that the vehicle reached the target altitude of 390 kilometers but was “just a half a kilometer per second short” of the target orbital velocity.

“This far exceeded our team’s expectations,” Kemp said.

Dec 15, 2020

Scientist Left “Speechless” After Opening Asteroid Samples

Posted by in categories: particle physics, space

“When we actually opened it, I was speechless,” JAXA scientist Hirotaka Sawada said, as quoted by The Guardian. “It was more than we expected and there was so much that I was truly impressed.”

The quality of the sample was outstanding.

“It wasn’t fine particles like powder, but there were plenty of samples that measured several millimeters across,” Sawada added, according to The Guardian.

Dec 15, 2020

Evolution of facial muscle anatomy in dogs

Posted by in category: evolution

Dogs are cool!

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Dec 15, 2020

Why This Surgery Replaces Knee With Backwards Foot?

Posted by in categories: biotech/medical, cyborgs

Rotationplasty is a bone cancer surgery for children that replaces the knee with a backwards foot so it can function as a knee joint for a prosthesis…

Dec 15, 2020

Earable computing: A new research area in the making

Posted by in categories: augmented reality, computing, health, mobile phones, security, wearables

CSL’s Systems and Networking Research Group (SyNRG) is defining a new sub-area of mobile technology that they call “earable computing.” The team believes that earphones will be the next significant milestone in wearable devices, and that new hardware, software, and apps will all run on this platform.

“The leap from today’s earphones to ‘earables’ would mimic the transformation that we had seen from basic phones to smartphones,” said Romit Roy Choudhury, professor in electrical and (ECE). “Today’s smartphones are hardly a calling device anymore, much like how tomorrow’s earables will hardly be a smartphone accessory.”

Instead, the group believes tomorrow’s earphones will continuously sense , run acoustic augmented reality, have Alexa and Siri whisper just-in-time information, track user motion and health, and offer seamless security, among many other capabilities.

Dec 15, 2020

When less is more: A single layer of atoms boosts the nonlinear generation of light

Posted by in categories: materials, particle physics

In a new study an international research team led by the University of Vienna has shown that structures built around a single layer of graphene allow for strong optical nonlinearities that can convert light. The team achieved this by using nanometer-sized gold ribbons to squeeze light, in the form of plasmons, into atomically-thin graphene. The results, which are published in Nature Nanotechnology are promising for a new family of ultra-small tunable nonlinear devices.

In the last years, a concerted effort has been made to develop plasmonic devices to manipulate and transmit through nanometer-sized devices. At the same time, it has been shown that nonlinear interactions can be greatly enhanced by using plasmons, which can arise when light interacts with electrons in a material. In a plasmon, light is bound to electrons on the surface of a conducting material, allowing plasmons to be much smaller than the light that originally created them. This can lead to extremely strong nonlinear interactions. However, plasmons are typically created on the surface of metals, which causes them to decay very quickly, limiting both the propagation length and nonlinear interactions. In this new work, the researchers show that the long lifetime of plasmons in and the strong nonlinearity of this material can overcome these challenges.

In their experiment, the research team led by Philip Walther at the University of Vienna (Austria), in collaboration with researchers from the Barcelona Institute of Photonic Sciences (Spain), the University of Southern Denmark, the University of Montpellier, and the Massachusetts Institute of Technology (USA) used stacks of two-dimensional materials, called heterostructures, to build up a nonlinear plasmonic device. They took a single atomic layer of graphene and deposited an array of metallic nanoribbons onto it. The metal ribbons magnified the incoming light in the graphene layer, converting it into graphene plasmons. These plasmons were then trapped under the gold nanoribbons, and produced light of different colors through a process known as harmonic generation. The scientists studied the generated light, and showed that, the nonlinear interaction between the graphene plasmons was crucial to describe the harmonic generation.

Dec 15, 2020

Physicists attempt to unify all forces of nature and rectify Einstein’s biggest failure

Posted by in categories: physics, space

But Einstein’s failed dream could ultimately become his ultimate triumph, as a small group of theoretical physicists rework his old ideas. It won’t necessarily bring all the forces of the universe together, but it could explain some of the most pressing issues facing modern science.

Dec 15, 2020

Gmail was messed up for a ‘significant’ number of users today

Posted by in category: futurism

Google says that a “significant subset” of Gmail users ran into errors with the service Tuesday afternoon.

While users could access their inboxes, they may have encountered “error messages, high latency, and/or other unexpected behavior,” the company wrote in a message on its service status page. Google said the issues with Gmail were resolved at 6:51PM ET.

The errors came just a day after many Google properties, including Gmail, YouTube, and Google Docs, were hit with a widespread outage.

Dec 15, 2020

A cool advance in thermoelectric conversion

Posted by in categories: engineering, nuclear energy, quantum physics

More than two-thirds of the energy used worldwide is ultimately ejected as “waste heat.” Within that reservoir of discarded energy lies a great and largely untapped opportunity, claim scientists in MIT’s Department of Nuclear Science and Engineering (NSE). As reported in a recent issue of Nature Communications, the MIT team—led by Assistant Professor Mingda Li, who heads NSE’s Quantum Matter Group—has achieved a breakthrough in thermoelectric generation, which offers a direct means of converting thermal energy, including waste heat, into electricity.

A , or difference, within a material such as a metal or semiconductor can, through a phenomenon known as the Seebeck effect, give rise to an that drives a current. “For many materials, the is too low to be useful,” explains NSE Research Scientist Fei Han. “Our goal is to find materials with conversion efficiencies high enough to make thermoelectric generation more practical.”

The efficiency of thermoelectric energy conversion is proportional to a material’s , electrical , and something called the “” squared; it is inversely proportional to the . Because efficiency goes up with temperature, most thermoelectric materials used today operate in the range of hundreds of degrees centigrade. “But in our lives, most of the stuff around us is at room temperature,” Han says. “That’s why we’re trying to discover new materials that work effectively at or below room temperature.”

Dec 15, 2020

Quantum Interference Phenomenon Identified That Occurs Through Time

Posted by in categories: particle physics, quantum physics

Since the very beginning of quantum physics, a hundred years ago, it has been known that all particles in the universe fall into two categories: fermions and bosons. For instance, the protons found in atomic nuclei are fermions, while bosons include photons — which are particles of light — as well as the BroutEnglert-Higgs boson, for which Francois Englert, a professor at ULB, was awarded a Nobel Prize in Physics in 2013.

Bosons — especially photons — have a natural tendency to clump together. One of the most remarkable experiments that demonstrated photons’ tendency to coalesce was conducted in 1987, when three physicists identified an effect that was since named after them: the Hong-Ou-Mandel effect. If two photons are sent simultaneously, each towards a different side of a beam splitter — a sort of semitransparent mirror — one could expect that each photon will be either reflected or transmitted.

Logically, photons should sometimes be detected on opposite sides of this mirror, which would happen if both are reflected or if both are transmitted. However, the experiment has shown that this never actually happens: the two photons always end up on the same side of the mirror, as though they ‘preferred’ sticking together! In an article published recently in US journal Proceedings of the National Academy of Sciences, Nicolas Cerf — a professor at the Centre for Quantum Information and Communication (École polytechnique de Bruxelles) — and his former PhD student Michael Jabbour — now a postdoctoral researcher at the University of Cambridge — describe how they identified another way in which photons manifest their tendency to stay together. Instead of a semi-transparent mirror, the researchers used an optical amplifier, called an active component because it produces new photons.