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Nov 11, 2019

New research synthesizes different aspects of causality in quantum field theory

Posted by in category: quantum physics

In current quantum field theory, causality is typically defined by the vanishing of field commutators for spacelike separations. Two researchers at the University of Massachusetts and Universidade Federal Rural in Rio de Janeiro have recently carried out a study discussing and synthesizing some of the key aspects of causality in quantum field theory. Their paper, published in Physical Review Letters, is the result of their investigation of a theory of quantum gravity commonly referred to as “quadratic gravity.”

“Like the ingredients of the standard model, quadratic gravity is a renormalizable , but it has some peculiar properties,” John Donoghue, one of the researchers who carried out the study, told Phys.org. “The small violation of causality is the most important of these and our goal was to understand this better. In the process, we realized that some of the insights are of more general interest and we decided to write our understanding as a Physical Review Letter, to share these insights more widely.”

The paper written by Donoghue and his colleague Gabriel Menezes synthesizes many different aspects of causality that have been part of quantum field for several decades now. The realization that there can be microscopic violations of causality in certain theories dates back to the 1960s, specifically to the work of physicists T.D. Lee and G.C. Wick. In their study, however, Donoghue and Menezes also drew inspiration from a more recent study carried out by Donal O’Connell, Benjamin Grinstein and Mark B. Wise.

Nov 11, 2019

New photonic liquid crystals could lead to next-generation displays

Posted by in categories: electronics, virtual reality

A new technique to change the structure of liquid crystals could lead to the development of fast-responding liquid crystals suitable for next generation displays—3D, augmented and virtual reality—and advanced photonic applications such as mirrorless lasers, bio-sensors and fast/slow light generation, according to an international team of researchers from Penn State, the Air Force Research Laboratory and the National Sun Yat-sen University, Taiwan.

“The liquid crystals we are working with are called blue-phase liquid crystals,” said Iam Choon Khoo, the William E. Leonhard Professor of Electrical Engineering, who is the corresponding author for this article. “The most important thing about this research is the fundamental understanding of what happens when you apply a field, which has led to the development of Repetitively-Applied Field technique. We believe that this method is almost a universal template that can be used for reconfiguring many similar types of liquid crystals and soft matter.”

Blue-phase liquid crystals typically self-assemble into a cubic photonic-crystal . The researchers believed that by creating other structures they could develop properties not present in the current form. After nearly two years of experimentation, they realized that by applying an intermittent electrical field and allowing the system to relax between applications and to dissipate accumulated heat, they could slowly coax the crystals into stable and field-free orthorhombic and tetragonal structures.

Nov 11, 2019

AI and automation will disrupt our world — but only Andrew Yang is warning about it

Posted by in categories: economics, education, employment, robotics/AI

Disruption of the job market and the economy from automation and the rise of artificial intelligence (AI) is one of the primary ideas animating Andrew Yang’s surprising campaign for the Democratic presidential nomination. Alone among the candidates, Yang is directly engaging with one of the central forces that will shape our futures.


A recent report from the consulting firm Deloitte found that, among more than a thousand surveyed American executives, 63 percent agreed with the statement that “to cut costs, my company wants to automate as many jobs as possible using AI,” and 36 percent already believe that job losses from AI-enabled automation should be viewed as an ethical issue. In other words, while media pundits dismiss worries about automation, executives at America’s largest companies are actively planning for it.

It may seem odd to worry about AI and automation at a time when the headline unemployment rate is below 4 percent. But it is important to remember that this metric only captures people who are actively seeking work. Consider that, in 1965, only 3 percent of American men between the ages of 25 and 54 — old enough to have completed education but too young to retire — were neither working nor actively looking for employment. Today, that number is about 11 percent.

Continue reading “AI and automation will disrupt our world — but only Andrew Yang is warning about it” »

Nov 10, 2019

SpaceX readies upgraded Starlink satellites for launch

Posted by in categories: internet, satellites

New satellites for SpaceX’s Starlink broadband network set for launch Monday from Cape Canaveral will debut several performance and safety upgrades, but they do not include changes to reduce the brightness of the satellites, a modification SpaceX says it will introduce on future Starlink craft to mitigate their impacts on ground-based astronomy.

The 60 Starlink satellites awaiting launch Monday will join 60 others launched in May. SpaceX says 1,440 of the flat-panel satellites are needed to provide Internet service over the “populated world,” a service level the company says could be achieved after 24 launches.

The Starlink network could offer service for parts of the United States and Canada after six launches, according to SpaceX.

Nov 10, 2019

Artificial Intelligence Is Too Important to Leave to Google and Facebook Alone

Posted by in category: robotics/AI

Let’s develop a public research consortium to take on useful projects that have no commercial prospects.

Nov 10, 2019

Fingerprint test could tell if people took drugs or skipped medication

Posted by in categories: biotech/medical, health, neuroscience

A fingerprint test developed by British scientists could tell if patients are skipping medication.

Forgetting or failing to take drugs can have serious consequences, particularly for people suffering from chronic conditions or those with mental health issues.

Non-adherence to prescribed medication is a major problem for the NHS, with some studies showing only 50 per cent of people take long-term drugs as instructed, at a cost of around £300 million in wasted medicine each year.

Nov 10, 2019

Scientists discover mood-altering brain receptor

Posted by in category: neuroscience

A brain receptor believed to be linked to negative moods has been discovered in a part of the brain that contributes to pain. The paper is published in Science.

Nov 10, 2019

Komodo to lead blockchain revolution with quantum-safe cryptography

Posted by in categories: bitcoin, computing, cryptocurrencies, encryption, quantum physics

Stadelmann said that Komodo is similar to Ethereum but it is 100% independent, free and open-sourced platform.

“As the world is getting digitised, it is all based on binary digits. Binary digits can have either 1 (on) or 0 (off). We don’t speak of bits anymore but quantum qubits or quantum bits, which can be in both 1 and 0 states at the same time. This qubit can attain so many states at the same time and they are also able to process calculations at a much faster rate than classical computers,” he said.

As a blockchain platform, Stadelmann said that Komodo is trying to solve the problem and has implemented quantum-safe cryptographic solutions for the past couple of years which will not be able to crack cryptographic signatures.

Nov 10, 2019

Hydrogen Boride Nanosheets: A Promising Material for Hydrogen Carrier

Posted by in categories: innovation, materials

Innovative nanosheets made from equal parts of hydrogen and boron have a greater capacity to store and release hydrogen compared with conventional metal-based materials.

Nov 10, 2019

‘Magnetic ionics’ breakthrough promises ultra-low-power microchips

Posted by in categories: computing, innovation

Circa 2018


Researchers at MIT (Cambridge, MA) and at Brookhaven National Laboratory (Upton, NY) have demonstrated a new approach to controlling magnetism in a microchip that could lead to next-generation memory and logic devices that consume drastically less power than current versions.