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Jul 8, 2020

Elon Musk’s Boring Company is hosting a competition to see who can dig tunnels faster than a snail

Posted by in category: Elon Musk

Elon Musk is hell bent on finding a way to dig tunnels cheaper and more quickly in order to avoid his least favourite thing: traffic.

Jul 8, 2020

First precise edits to mitochondrial DNA achieved with weird enzyme

Posted by in category: biotech/medical

Weird enzyme enables researchers to study — and potentially treat — deadly diseases. Feat enables researchers to study — and perhaps treat — deadly diseases.

Jul 8, 2020

Research advances understanding of how the brain focuses while ignoring distractions

Posted by in category: neuroscience

When trying to complete a task we are constantly bombarded by distracting stimuli. How does the brain filter out these distractions and enable us to focus on the task at hand? Psychologists at the University of California, Riverside, have made a discovery that could lead to an answer.

Experimenting on mice, they located the precise spot in the brain where distracting stimuli are blocked. The blocking disables the brain from processing these stimuli, which allows concentration on a particular task to proceed.

Edward Zagha, an assistant professor of psychology, and his team trained mice in a sensory detection task with target and distractor stimuli. The mice learned to respond to rapid stimuli in the target field and ignore identical stimuli in the opposite distractor field. The team used a novel imaging technique, which allows for high spatiotemporal resolution with a cortex-wide field of view, to find where in the brain the distractor stimuli are blocked, resulting in no further signal transmission within the cortex and, therefore, no triggering of a motor response.

Jul 8, 2020

Drugs, money and misleading evidence

Posted by in categories: biotech/medical, economics

Child psychiatrist Jon Jureidini and philosopher Leemon McHenry dispute the assumption that all approved drugs and medical devices are safe and effective. They warn that when clinical science is hitched to the pharmaceutical industry’s dash for profits, the scientific method is undermined by marketing spin and cherry-picking of data. They propose a solution inspired by philosopher of science Karl Popper: take drug testing out of the hands of manufacturers.”


It’s time to take trials out of the hands of pharmaceutical makers, argues the latest in a long line of books on corruption and the pharmaceutical industry.

Jul 8, 2020

Large-scale integration of artificial atoms in hybrid photonic circuits

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

A central challenge in developing quantum computers and long-range quantum networks is the distribution of entanglement across many individually controllable qubits1. Colour centres in diamond have emerged as leading solid-state ‘artificial atom’ qubits2,3 because they enable on-demand remote entanglement4, coherent control of over ten ancillae qubits with minute-long coherence times5 and memory-enhanced quantum communication6. A critical next step is to integrate large numbers of artificial atoms with photonic architectures to enable large-scale quantum information processing systems. So far, these efforts have been stymied by qubit inhomogeneities, low device yield and complex device requirements. Here we introduce a process for the high-yield heterogeneous integration of ‘quantum microchiplets’—diamond waveguide arrays containing highly coherent colour centres—on a photonic integrated circuit (PIC). We use this process to realize a 128-channel, defect-free array of germanium-vacancy and silicon-vacancy colour centres in an aluminium nitride PIC. Photoluminescence spectroscopy reveals long-term, stable and narrow average optical linewidths of 54 megahertz (146 megahertz) for germanium-vacancy (silicon-vacancy) emitters, close to the lifetime-limited linewidth of 32 megahertz (93 megahertz). We show that inhomogeneities of individual colour centre optical transitions can be compensated in situ by integrated tuning over 50 gigahertz without linewidth degradation. The ability to assemble large numbers of nearly indistinguishable and tunable artificial atoms into phase-stable PICs marks a key step towards multiplexed quantum repeaters7,8 and general-purpose quantum processors9,10,11,12.

Jul 8, 2020

Beyond Comprehension –“Neutron Star’s Superfluid, Superconducting Core at Supranuclear Densities”

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

Neutron stars are an end state of stellar evolution, says astrophysicist Paul Lasky, at Australia’s Monash University and OzGrav. “They consist of the densest observable matter in the universe, under conditions that are impossible to produce in the laboratory, and theoretical modeling of the matter requires extrapolation by many orders of magnitude beyond the point where nuclear physics is well understood.”

“Gravitational-wave astronomy is reshaping our understanding of the universe,” said Lasky, about a new study co-authored by the ARC Center of Excellence for Gravitational Wave Discovery (OzGrav) that makes a compelling case for the development of “NEMO” —a new observatory in Australia that could deliver on some of the most exciting gravitational-wave science next-generation detectors have to offer, but at a fraction of the cost.

The study today presents the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimized to study nuclear physics with merging neutron stars, using high circulating laser power, quantum squeezing and a detector topology specially designed to achieve the high frequency sensitivity necessary to probe nuclear matter using gravitational waves.

Jul 8, 2020

Physicists use oscillations of atoms to control a phase transition

Posted by in categories: chemistry, particle physics

The goal of ‘femtochemistry’ is to film and control chemical reactions with short flashes of light. Using consecutive laser pulses, atomic bonds can be excited precisely and broken as desired. So far, this has been demonstrated for selected molecules. Researchers at the University of Göttingen and the Max Planck Institute for Biophysical Chemistry have now succeeded in transferring this principle to a solid, controlling its crystal structure on the surface. The results have been published in the journal Nature.

The team, led by Jan Gerrit Horstmann and Professor Claus Ropers, evaporated an extremely thin layer of indium onto a silicon crystal and then cooled the crystal down to −220 degrees Celsius. While the indium form conductive metal chains on the at room temperature, they spontaneously rearrange themselves into electrically insulating hexagons at such low temperatures. This process is known as the transition between two phases—the metallic and the insulating—and can be switched by laser pulses. In their experiments, the researchers then illuminated the cold surface with two short laser pulses and immediately afterwards observed the arrangement of the indium atoms using an electron beam. They found that the rhythm of the has a considerable influence on how efficiently the surface can be switched to the metallic state.

This effect can be explained by oscillations of the atoms on the surface, as first author Jan Gerrit Horstmann explains: “In order to get from one state to the other, the atoms have to move in different directions and in doing so overcome a sort of hill, similar to a roller coaster ride. A single laser pulse is not enough for this, however, and the atoms merely swing back and forth. But like a rocking motion, a second pulse at the right time can give just enough energy to the system to make the transition possible.” In their experiments the physicists observed several oscillations of the atoms, which influence the conversion in very different ways.

Jul 8, 2020

A 2020 view of Mars just got released

Posted by in category: space

Curiosity Mars Rover’s Summer Road Trip Has Begun. The footage in this video was taken between February and April 2020.

Jul 8, 2020

Cleaning Robots May Be the Future of Health for Humans

Posted by in categories: health, robotics/AI

Researchers at MIT are working with Ava Robotics to provide a sanitary solution to high foot traffic spaces.

Jul 8, 2020

Contest between superconductivity and insulating states in ‘magic angle’ graphene

Posted by in categories: materials, physics

If you stack two layers of graphene one on top of the other, and rotate them at an angle of 1.1º (no more and no less) from each other—the so-called ‘magic-angle,’ experiments have proven that the material can behave like an insulator, where no electrical current can flow, and at the same can also behave like a superconductor, where electrical currents can flow without resistance.

This major finding took place in 2018. Last year, in 2019, while ICFO researchers were improving the quality of the device used to replicate such breakthroughs, they stumbled upon something even bigger and totally unexpected. They were able to observe a zoo of previously unobserved superconducting and correlated states, in addition to an entirely new set of magnetic and topological states, opening a completely new realm of richer physics.

So far, there is no theory that has been able to explain superconductivity in magic angle graphene at the microscopic level. However, this finding has triggered many studies, which are trying to understand and unveil the physics behind all these phenomena that occur in this material. In particular, scientists drew analogies to unconventional high temperature superconductors—the cuprates, which hold the record highest superconducting temperatures, only 2 times lower than . Their microscopic mechanism of the superconducting phase is still not understood, 30 years after its discovery. However, similarly to magic angle twisted bi-layer graphene (MATBG), it is believed that an insulating phase is responsible for the superconducting phase in proximity to it. Understanding the relationship between the superconducting and insulating phases is at the center of researcher’s interest, and could lead to a big breakthrough in superconductivity research.