In a surprising discovery, Princeton physicists have observed an unexpected quantum behavior in an insulator made from a material called tungsten ditelluride. This phenomenon, known as quantum oscillation, is typically observed in metals rather than insulators, and its discovery offers new insights into our understanding of the quantum world. The findings also hint at the existence of an entirely new type of quantum particle.

The discovery challenges a long-held distinction between metals and insulators, because in the established quantum theory of materials, insulators were not thought to be able to experience quantum oscillations.

"If our interpretations are correct, we are seeing a fundamentally new form of quantum matter," said Sanfeng Wu, assistant professor of physics at Princeton University and the senior author of a recent paper in Nature detailing this new discovery. "We are now imagining a wholly new quantum world hidden in insulators. It's possible that we simply missed identifying them over the last several decades."

The observation of quantum oscillations has long been considered a hallmark of the difference between metals and insulators. In metals, electrons are highly mobile, and resistivity — the resistance to electrical conduction — is weak. Nearly a century ago, researchers observed that a magnetic field, coupled with very low temperatures, can cause electrons to shift from a "classical" state to a quantum state, causing oscillations in the metal's resistivity. In insulators, by contrast, electrons cannot move and the materials have very high resistivity, so quantum oscillations of this sort are not expected to occur, no matter the strength of magnetic field applied.

In summary

• A Swinburne-led team has demonstrated the world's fastest and most powerful optical neuromorphic processor for artificial intelligence
• The neuromorphic processor operates faster than 10 trillion operations per second and is capable of processing ultra-large scale data
• This breakthrough has been published in the prestigious journal Nature and represents an enormous leap forward for neural networks and neuromorphic processing

An international team of researchers led by Swinburne University of Technology has demonstrated the world's fastest and most powerful optical neuromorphic processor for artificial intelligence (AI), which operates faster than 10 trillion operations per second (TeraOPs/s) and is capable of processing ultra-large scale data. Published in the prestigious journal Nature, this breakthrough represents an enormous leap forward for neural networks and neuromorphic processing in general.

Artificial neural networks, a key form of AI, can 'learn' and perform complex operations with wide applications to computer vision, natural language processing, facial recognition, speech translation, playing strategy games, medical diagnosis and many other areas. Inspired by the biological structure of the brain's visual cortex system, artificial neural networks extract key features of raw data to predict properties and behaviour with unprecedented accuracy and simplicity.

Led by Swinburne's Professor David Moss, Dr Xingyuan (Mike) Xu (Swinburne, Monash University) and Distinguished Professor Arnan Mitchell from RMIT University, the team achieved an exceptional feat in optical neural networks: dramatically accelerating their computing speed and processing power.

Using years' worth of data collected from ice-covered habitats all over the world, a Montana State University team has discovered new insights into the processes that support microbial life underneath ice sheets and glaciers, and the role those organisms play in perpetuating life through ice ages and, perhaps, in seemingly inhospitable environments on other planets.

Doctoral candidate Eric Dunham of MSU's Department of Microbiology and Immunology in the College of Agriculture, along with mentor Eric Boyd, published their findings in the journal Proceedings of the National Academy of Sciences in December 2020. The work examines the ways water and microbes interact with the bedrock beneath glaciers, using samples of sediment taken from glacial sites in Canada and Iceland.

"We kept finding organisms in these systems that were supported by hydrogen gas," said Boyd of the inspiration for the project. "It initially didn't make sense, because we couldn't figure out where that hydrogen gas was coming from under these glaciers."

John P. A. Ioannidis, Professor of Medicine and Epidemiology, Professor Jay Bhattacharya, a founding signatory of the Great Barrington Declaration, and other colleagues at Stanford University, have published a new, fully peer-reviewed study. Their objective was to assess the impact of the non-pharmaceutical interventions adopted by many countries in response to the outbreak of COVID-19.

The spread of COVID-19 has led to multiple policy responses that aim to reduce the transmission of the SARS-CoV-2. The principal goal of these so-called non-pharmaceutical interventions (NPIs) is to reduce transmission in the absence of pharmaceutical options in order to reduce resultant death, disease, and health system overload. Some of the most restrictive NPI policies include mandatory stay-at-home and business closure orders ("lockdowns"). The early adoption of these more restrictive non-pharmaceutical interventions (mrNPIs) in early 2020 was justified because of the rapid spread of the disease, overwhelmed health systems in some hard-hit places, and substantial uncertainty about the virus's morbidity and mortality.

Because of the potential harmful health effects of mrNPI, including hunger, opioid-related overdoses, missed vaccinations, increase in non-COVID-19 diseases from missed health services, domestic abuse, mental health and suicidality as well as a host of economic consequences with health implications, it is increasingly recognized that their postulated benefits deserve careful study... We propose an approach that balances the strengths of empirical analyses while taking into consideration underlying epidemic dynamics. We compare epidemic spread in places that implemented mrNPIs to counterfactuals that implemented only less-restrictive NPIs (lrNPIs). In this way, it may be possible to isolate the role of mrNPIs, net of lrNPIs and epidemic dynamics. Here, we use Sweden and South Korea as the counterfactuals to isolate the effects of mrNPIs in countries that implemented mrNPIs as well as lrNPIs. Unlike most of its neighbors that implemented mandatory stay-at-home and business closures, Sweden's approach in the early stages of the pandemic relied entirely on lrNPIs, including social distancing guidelines, discouraging of international and domestic travel, and a ban on large gatherings. South Korea also did not implement mrNPIs. Its strategy relied on intensive investments in testing, contact tracing, and isolation of infected cases and close contacts.

Most of the mangrove forests on the coasts of Oman disappeared about 6,000 years ago. Until now, the reason for this was not entirely clear. A current study of the University of Bonn (Germany) now sheds light on this: It indicates that the collapse of coastal ecosystems was caused by climatic changes. In contrast, falling sea level or overuse by humans are not likely to be the reasons. The speed of the mangrove extinction was dramatic: Many of the stocks were irreversibly lost within a few decades. The results are published in the journal Quaternary Research.

About 87 million miles (140 million kilometers) above the Grand Canyon, an even larger, grander abyss cuts through the gut of the Red Planet. Known as Valles Marineris, this system of deep, vast canyons runs more than 2,500 miles (4,000 km) along the Martian equator, spanning nearly a quarter of the planet's circumference. This gash in the bedrock of Mars is nearly 10 times as long as Earth's Grand Canyon and three times deeper, making it the single largest canyon in the solar system — and, according to ongoing research from the University of Arizona (UA) in Tucson, one of the most mysterious.

Often considered the world's oddest mammal, Australia's beaver-like, duck-billed platypus exhibits an array of bizarre characteristics: it lays eggs instead of giving birth to live babies, sweats milk, has venomous spurs and is even equipped with 10 sex chromosomes. Now, an international team of researchers led by University of Copenhagen has conducted a unique mapping of the platypus genome and found answers regarding the origins of a few of its stranger features.

It lays eggs, but nurses, it is toothless, has a venomous spur, has webbed feet, fur that glows and has 10 sex chromosomes. Ever since Europeans discovered the platypus in Australia during the late 1700's, the quirky, duck-billed, semi-aquatic creature has baffled scientific researchers.

The transition from the Medieval Warm Period to the Little Ice Age was apparently accompanied by severe droughts between 1302 and 1307 in Europe; this preceded the wet and cold phase of the 1310s and the resulting great famine of 1315-21.


In the journal Climate of the Past, researchers from the Leibniz Institutes for the History and Culture of Eastern Europe (GWZO) and Tropospheric Research (TROPOS) write that the 1302-07 weather patterns display similarities to the 2018 weather anomaly, in which continental Europe experienced exceptional heat and drought.

Both the medieval and recent weather patterns resemble the stable weather patterns that have occurred more frequently since the 1980s due to the increased warming of the Arctic. According to the Leibniz researchers' hypothesis based on their comparison of the 1302-07 and 2018 droughts, transitional phases in the climate are always characterized by periods of low variability, in which weather patterns remain stable for a long time.

Viruses do not disappear. When a novel virus is introduced to a naive population there will be an epidemic. Spread will be exponential, some susceptible people will die but eventually we will reach a point where there is sufficient population immunity that spread is slowed and the virus stops spreading in an epidemic fashion. Thereafter, localised outbreaks can still occur and susceptible people can still die but there is no longer a risk of epidemic spread because every outbreak is contained by population immunity.

Coronaviruses are seasonal, so it is only now that we have had some winter weather that we can assess what endemic Covid will be like.

Figure 1 shows the sharp spike in excess deaths seen with epidemic Covid in spring. These deaths were in excess of the usual winter hump. Compared with previous years, this year's winter excess deaths started earlier but the shape of the curve is consistent with previous years. However, we have now reached the bizarre situation where so many deaths are being labelled as caused by Covid that, for the first time ever, this winter there are fewer non-Covid deaths in winter weeks than there were in summer.

Doctors have noticed that unlike in previous years, their patients have low white blood cell and platelet counts, sudden hypoxias and bilateral atypical pneumonias. These features can be seen in other pneumonias but are characteristic of Covid and are being seen in large numbers currently.

Physicists have identified a new state of matter, hidden inside the mysterious transformations that take place between liquid and solid states of glass.

The glass transition holds a lot of fascination for scientists, and the new state of matter - called 'liquid glass' - exhibits behaviour at the microscopic level that hasn't been seen before, marking it as separate from previously observed phenomena.

This new state seems to exist between a solid and a colloid (such as a gel): homogeneous mixtures with particles that are microscopic but still bigger than atoms and molecules, and easier to study. In this case tiny, tailor-made plastic ellipsoidal colloids were created and mixed together in a solvent.