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Nov 20, 2023

Deep within the Earth, iron oxide withstands extreme temperatures and pressures

Posted by in categories: biotech/medical, chemistry

The core–mantle boundary (CMB) is the interface between the Earth’s iron metal core and the thick rocky layer of mantle just above the core. It is a world of extremes—temperatures thousands of degrees Fahrenheit and pressures over a million times the pressure at the surface of the Earth. While it may seem far away from our environment on Earth’s surface, plumes of material from the CMB can ascend upwards through the planet over tens of millions of years, influencing the chemistry, geologic structure, and plate tectonics of the surface world where we live.

Though scientists cannot travel to the center of the Earth to study the CMB, they can get clues about what lies beneath the planet’s surface by measuring earthquakes. Seismic waves travel at different speeds depending on the material they are traveling through, allowing researchers to infer what lies deep below the surface using seismic signatures. This is analogous to how ultrasound uses waves of sound to image inside of the human body.

Recent research shows that the base of Earth’s mantle is actually complex and heterogeneous—in particular, there are mountain-like regions where seismic waves mysteriously slow down. These blobs, named ultralow velocity zones (ULVZs) and first discovered by Caltech’s Don Helmberger, are dozens of kilometers thick and lie around 3,000 kilometers beneath our feet.

Nov 20, 2023

Research demonstrates new type of ferromagnetism with completely different alignment of magnetic moments

Posted by in categories: employment, quantum physics

For a magnet to stick to a fridge door, several physical effects inside of it need to work together perfectly. The magnetic moments of its electrons all point in the same direction, even if no external magnetic field forces them to do so.

This happens because of the so-called exchange interaction, a combination of electrostatic repulsion between electrons and quantum mechanical effects of the electron spins, which, in turn, are responsible for the . This is a common explanation for the fact that certain materials like iron or nickel are ferromagnetic or permanently magnetic, as long as one does not heat them above a particular temperature.

At ETH in Zurich, a team of researchers led by Ataç Imamoğlu at the Institute for Quantum Electronics and Eugene Demler at the Institute for Theoretical Physics have now detected a new type of ferromagnetism in an artificially produced material, in which the alignment of the magnetic moments comes about in a completely different way. They recently published their results in the journal Nature.

Nov 20, 2023

Three-pronged approach discerns qualities of quantum spin liquids

Posted by in categories: computing, particle physics, quantum physics

In 1973, physicist Phil Anderson hypothesized that the quantum spin liquid, or QSL, state existed on some triangular lattices, but he lacked the tools to delve deeper. Fifty years later, a team led by researchers associated with the Quantum Science Center headquartered at the Department of Energy’s Oak Ridge National Laboratory has confirmed the presence of QSL behavior in a new material with this structure, KYbSe2.

QSLs—an unusual state of matter controlled by interactions among entangled, or intrinsically linked, magnetic atoms called spins—excel at stabilizing quantum mechanical activity in KYbSe2 and other delafossites. These materials are prized for their layered triangular lattices and promising properties that could contribute to the construction of high-quality superconductors and quantum computing components.

The paper, published in Nature Physics, features researchers from ORNL; Lawrence Berkeley National Laboratory; Los Alamos National Laboratory; SLAC National Accelerator Laboratory; the University of Tennessee, Knoxville; the University of Missouri; the University of Minnesota; Stanford University; and the Rosario Physics Institute.

Nov 20, 2023

Scientists set the stage for quantum chemistry in space on NASA’s cold atom lab

Posted by in categories: biotech/medical, chemistry, mobile phones, quantum physics

For the first time in space, scientists have produced a mixture of two quantum gases made of two types of atoms. Accomplished with NASA’s Cold Atom Laboratory aboard the International Space Station, the achievement marks another step toward bringing quantum technologies currently available only on Earth into space.

Physicists at Leibniz University Hannover (LUH), part of a collaboration led by Prof. Nicholas Bigelow, University of Rochester, provided the theoretical calculations necessary for this achievement. While quantum tools are already used in everything from cell phones to GPS to , in the future, quantum tools could be used to enhance the study of planets, including our own, as well as to help solve mysteries of the universe and deepen our understanding of the fundamental laws of nature.

The new work, performed remotely by scientists on Earth, is described in Nature.

Nov 20, 2023

From concrete quarks to QCD: a personal perspective

Posted by in categories: materials, particle physics

The simple story line that ‘Gell-Mann and Zweig invented quarks in 1964 and the quark model was generally accepted after 1968 when deep inelastic electron scattering experiments at SLAC showed that they are real’ contains elements of the truth, but is not true. This paper describes the origins and development of the quark model until it became generally accepted in the mid-1970s, as witnessed by a spectator and some-time participant who joined the field as a graduate student in October 1964. It aims to ensure that the role of Petermann is not overlooked, and Zweig and Bjorken get the recognition they deserve, and to clarify the role of Serber.

Nov 20, 2023

Quantum chemistry experiment on ISS creates exotic 5th state of matter

Posted by in categories: chemistry, particle physics, quantum physics, space

Researchers created a quantum gas containing two types of atoms on the ISS, in a first for space-based research.

Nov 20, 2023

Meta-reinforcement learning via orbitofrontal cortex

Posted by in category: robotics/AI

The authors show that neural activity and synaptic plasticity in the orbitofrontal cortex mediate multiple timescales of reinforcement learning (RL) for meta-RL, which parallels a form of meta-RL in artificial intelligence.

Nov 20, 2023

“Make It Real” AI prototype wows devs by turning drawings into working software

Posted by in categories: robotics/AI, security

On Wednesday, a collaborative whiteboard app maker called “tldraw” made waves online by releasing a prototype of a feature called “Make it Real” that lets users draw an image of software and bring it to life using AI. The feature uses OpenAI’s GPT-4V API to visually interpret a vector drawing into functioning Tailwind CSS and JavaScript web code that can replicate user interfaces or even create simple implementations of games like Breakout.

Users can experiment with a live demo of Make It Real online. However, running it requires providing an API key from OpenAI, which is a security risk. If others intercept your API key, they could use it to rack up a very large bill in your name (OpenAI charges by the amount of data moving into and out of its API). Those technically inclined can run the code locally, but it will still require OpenAI API access.

Nov 20, 2023

Get ready for artificial ‘superintelligence’

Posted by in category: robotics/AI

Plus! ‘Strongest ever’ gamma ray blast over Earth.

Nov 20, 2023

Superintelligent AI: The Doomers

Posted by in categories: existential risks, robotics/AI

Does artificial general intelligence pose an existential risk?