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Jan 5, 2023

Innovation strengthens electron-triggered light emissions for quantum-based computational and communications systems

Posted by in categories: computing, nanotechnology, quantum physics, solar power, sustainability

The way electrons interact with photons of light is a vital part of many modern technologies, from lasers to solar panels to LEDs. But the interaction is inherently weak because of a major mismatch in scale: the wavelength of visible light is about 1,000 times larger than an electron, so the way the two things affect each other is limited by that disparity.

Now, researchers at The University of Hong Kong (HKU), MIT and other universities say they have come up with an innovative way to make more robust interactions between photons and electrons possible, that produces a hundredfold increase in the emission of light from a phenomenon called Smith-Purcell radiation. The findings have potential ramifications for both and fundamental scientific research, although it will require more years of investigation to put into practice.

The findings are published in Nature by Dr. Yi Yang (Assistant Professor of the Department of Physics at HKU and a former postdoc at MIT), Dr. Charles Roques-carmes (Postdoctoral Associate at MIT) and Professors Marin Soljačić and John Joannopoulos (MIT professors). The research team also included Steven Kooi at MIT’s Institute for Soldier Nanotechnologies, Haoning Tang and Eric Mazur at Harvard University, Justin Beroz at MIT, and Ido Kaminer at Technion-Israel Institute of Technology.

Jan 5, 2023

Ramses III against the Sea Peoples

Posted by in category: military

Usermaatre Meryamun, better known as Ramses III (1184 – 1,153 BC), was the second and most important king of the Twentieth Dynasty (1186 – 1,069 BC).

The particularities of his extensive reign, the significance of his military victories against the so-called “Sea Peoples”, and the magnificent state of preservation of his funerary temple in Medinet Habu (Western Thebes) made him one of the most important pharaohs of all the period of the Egyptian New Kingdom (approx. 1,550 – 1,069 BC).

Jan 5, 2023

When A Teacher Learned From His Student

Posted by in category: futurism

A brief story depicting Hardy-Ramanujan relationship.

Jan 5, 2023

New type of entanglement lets scientists ‘see’ inside nuclei

Posted by in categories: biotech/medical, neuroscience, quantum physics

Nuclear physicists have found a new way to use the Relativistic Heavy Ion Collider (RHIC)—a particle collider at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory—to see the shape and details inside atomic nuclei. The method relies on particles of light that surround gold ions as they speed around the collider and a new type of quantum entanglement that’s never been seen before.

Through a series of quantum fluctuations, the particles of light (a.k.a. photons) interact with gluons—gluelike particles that hold quarks together within the protons and neutrons of nuclei. Those interactions produce an intermediate particle that quickly decays into two differently charged “pions” (π). By measuring the velocity and angles at which these π+ and π- particles strike RHIC’s STAR detector, the scientists can backtrack to get crucial information about the photon—and use that to map out the arrangement of gluons within the nucleus with higher precision than ever before.

“This technique is similar to the way doctors use positron emission tomography (PET scans) to see what’s happening inside the brain and other body parts,” said former Brookhaven Lab physicist James Daniel Brandenburg, a member of the STAR collaboration who joined The Ohio State University as an assistant professor in January 2023. “But in this case, we’re talking about mapping out features on the scale of femtometers —quadrillionths of a meter—the size of an individual proton.”

Jan 5, 2023

Triad of Menkaure: What makes it so unique?

Posted by in category: futurism

2548–2530 BC. Egyptian Museum in Cairo, Egypt.

This Menkaure Triad is the most important piece of the entire set of statues found by George Reisner in the vicinity of the Giza temple. The sculpture stood out from the beginning for its realism, excellence, and austere beauty, qualities that have made it one of the most emblematic works of the Cairo Museum.

During excavations in Giza in 1908, the American Egyptologist George Reisner located diverse sculptural works of magnificent craftsmanship buried next to the temple of Menkaure.

Jan 5, 2023

How Claude Shannon’s Concept of Entropy Quantifies Information

Posted by in category: futurism

What’s a message, really? Claude Shannon recognized that the elemental ingredient is surprise.

Jan 5, 2023

New radar allows cars to spot hazards around corners

Posted by in categories: robotics/AI, transportation

Using radar commonly deployed to track speeders and fastballs, researchers have developed an automated system that will allow cars to peer around corners and spot oncoming traffic and pedestrians.

The system, easily integrated into today’s vehicles, uses Doppler radar to bounce radio waves off surfaces such as buildings and parked automobiles. The radar signal hits the surface at an angle, so its reflection rebounds off like a cue ball hitting the wall of a pool table. The signal goes on to strike objects hidden around the corner. Some of the radar signal bounces back to detectors mounted on the car, allowing the system to see objects around the corner and tell whether they are moving or stationary.

“This will enable cars to see occluded objects that today’s lidar and camera sensors cannot record, for example, allowing a self-driving vehicle to see around a dangerous intersection” said Felix Heide, an assistant professor of computer science at Princeton University and one of researchers. “The radar sensors are also relatively low-cost, especially compared to lidar sensors, and scale to mass production.”

Jan 5, 2023

Amazon CEO says company will layoff more than 18,000 workers

Posted by in categories: economics, employment

Amazon is laying off 18,000 employees, the tech giant said Wednesday, representing the single largest number of jobs cut at a technology company since the industry began aggressively downsizing last year.

In a blog post, Amazon CEO Andy Jassy wrote that the staff reductions were set off by the uncertain economy and the company’s rapid hiring over the last several years.

The cuts will primarily hit the company’s corporate workforce and will not affect hourly warehouse workers. In November, Amazon had reportedly been planning to lay off around 10,000 employees but on Wednesday, Jassy pegged the number of jobs to be shed by the company to be higher than that, as he put it, “just over 18,000.”

Jan 5, 2023

The Eccentricities of J. Robert Oppenheimer

Posted by in categories: chemistry, cosmology, military, particle physics, quantum physics

The so-called “Father of the Atomic Bomb” J. Robert Oppenheimer was once described as “a genius of the nuclear age and also the walking, talking conscience of science and civilization”. Born at the outset of the 20th century, his early interests in chemistry and physics would in the 1920s bring him to Göttingen University, where he worked alongside his doctoral supervisor Max Born (1882−1970), close lifelong friend Paul Dirac (1902−84) and eventual adversary Werner Heisenberg (1901−76). This despite the fact that even as early as in his youth, Oppenheimer was singled out as both gifted and odd, at times even unstable. As a child he collected rocks, wrote poetry and studied French literature. Never weighing more than 130 pounds, throughout his life he was a “tall and thin chainsmoker” who once stated that he “needed physics more than friends” who at Cambridge University was nearly charged with attempted murder after leaving a poisoned apple on the desk of one of his tutors. Notoriously abrupt and impatient, at Göttingen his classmates once gave their professor Born an ultimatum: “either the ‘child prodigy’ is reigned in, or his fellow students will boycott the class”. Following the successful defense of his doctoral dissertation, the professor administering the examination, Nobel Laureate James Franck (1882−1964) reportedly left the room stating.

“I’m glad that’s over. He was at the point of questioning me”

From his time as student at Harvard, to becoming a postgraduate researcher in Cambridge and Göttingen, a professor at UC Berkeley, the scientific head of the Manhattan project and after the war, the Director of the Institute for Advanced Study, wherever Oppenheimer went he could hold his own with the greatest minds of his age. Max Born, Paul Dirac, John von Neumann, Niels Bohr, Albert Einstein, Kurt Gödel, Richard Feynman, they all admired “Oppie”. When he died in 1967, his published articles in physics totaled 73, ranging from topics in quantum field theory, particle physics, the theory of cosmic radiations to nuclear physics and cosmology. His funeral was attended by over 600 people, and included numerous associates from academia and research as well as government officials, heads of military, even the director of the New York City Ballet.

Jan 5, 2023

Shrinking hydrogels enlarge nanofabrication options

Posted by in categories: biological, nanotechnology

Researchers from Carnegie Mellon University and the Chinese University of Hong Kong have developed a strategy for creating ultrahigh-resolution, complex 3D nanostructures out of various materials.

Carnegie Mellon University’s Yongxin (Leon) Zhao and the Chinese University of Hong Kong’s Shih-Chi Chen have a big idea for manufacturing nanodevices.

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