Lifeboat Foundation

Comet 67P/C-G is a dusty object. As it neared its closest approach to the Sun in late July and August 2015, instruments on Rosetta recorded a huge amount of dust enshrouding the comet.

This is tied to the comet’s proximity to our parent star, its heat causing the comet’s nucleus to release gases into space, lifting the dust along. Spectacular jets were also observed, blasting more dust away from the comet. This disturbed, ejected material forms the ‘coma’, the gaseous envelope encasing the comet’s nucleus, and can create a beautiful and distinctive tail.

A single image from Rosetta’s OSIRIS instrument can contain hundreds of dust particles and grains surrounding the 4 km-wide comet nucleus. Sometimes, even larger chunks of material left the surface of 67P/C-G — as shown here.

A team of researchers at the Niels Bohr Institute, University of Copenhagen, have succeeded in entangling two very different quantum objects. The result has several potential applications in ultra-precise sensing and quantum communication and is now published in Nature Physics.

Entanglement is the basis for quantum communication and quantum sensing. It can be understood as a quantum link between two objects which makes them behave as a single quantum object.

Researchers succeeded in making entanglement between a mechanical oscillator—a vibrating dielectric membrane—and a cloud of atoms, each acting as a tiny magnet, or what physicists call “spin.” These very different entities were possible to entangle by connecting them with photons, particles of light. Atoms can be useful in processing quantum information and the membrane—or mechanical quantum systems in general—can be useful for storage of quantum information.

A top goal in cosmology is to precisely measure the total amount of matter in the universe, a daunting exercise for even the most mathematically proficient. A team led by scientists at the University of California, Riverside, has now done just that.

Reporting in the Astrophysical Journal, the team determined that matter makes up 31% of the total amount of matter and energy in the universe, with the remainder consisting of dark energy.

“To put that amount of matter in context, if all the matter in the universe were spread out evenly across space, it would correspond to an average mass density equal to only about six hydrogen atoms per cubic meter,” said first author Mohamed Abdullah, a graduate student in the UCR Department of Physics and Astronomy. “However, since we know 80% of matter is actually dark matter, in reality, most of this matter consists not of hydrogen atoms but rather of a type of matter which cosmologists don’t yet understand.”

A new study proves that far from being mere mathematical artifacts, particles that are indistinguishable from one another can be a potent resource in real-world experiments.

Astrophysicists at the University of Jena (Germany) prove that dust particles in space are mixed with ice.

The matter between the stars in a galaxy – called the interstellar medium – consists not only of gas, but also of a great deal of dust. At some point in time, stars and planets originated in such an environment, because the dust particles can clump together and merge into celestial bodies. Important chemical processes also take place on these particles, from which complex organic – possibly even prebiotic – molecules emerge. However, for these processes to be possible, there has to be water. In particularly cold cosmic environments, water occurs in the form of ice. Until now, however, the connection between ice and dust in these regions of space was unclear. A research team from Friedrich Schiller University Jena and the Max Planck Institute for Astronomy has now proven that the dust particles and the ice are mixed. They report their findings in the current issue of the research journal Nature Astronomy.

Better modelling of physico-chemical processes in space.

Researchers in Singapore have built a refrigerator that’s just three atoms big.

This quantum fridge won’t keep your drinks cold, but it’s cool proof of physics operating at the smallest scales. The work is described in a paper published in Nature Communications (“Quantum absorption refrigerator with trapped ions”).

Researchers have built tiny ‘heat engines’ before, but quantum fridges existed only as proposals until the team at the Centre for Quantum Technologies at the National University of Singapore chilled with their atoms.

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New measurements of a weird but simple atom, one without a nucleus, suggest it may have unexpected properties. Scientists find this troubling.

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Through a one-of-a-kind experiment at the Department of Energy’s Oak Ridge National Laboratory, nuclear physicists have precisely measured the weak interaction between protons and neutrons. The result quantifies the weak force theory as predicted by the Standard Model of Particle Physics.

The team’s weak force observation, detailed in Physical Review Letters, was measured through a precision experiment called n3He, or n-helium-3, that ran at ORNL’s Spallation Neutron Source, or SNS. Their finding yielded the smallest uncertainty of any comparable weak force measurement in the nucleus of an atom to date, which establishes an important benchmark.

Continue reading “Scientists achieve higher precision weak force measurement between protons, neutrons” »

Nanoscale vortices known as skyrmions can be created in many magnetic materials. For the first time, researchers at PSI have managed to create and identify antiferromagnetic skyrmions with a unique property: critical elements inside them are arranged in opposing directions. Scientists have succeeded in visualizing this phenomenon using neutron scattering. Their discovery is a major step towards developing potential new applications, such as more efficient computers. The results of the research are published today in the journal Nature.

Whether a material is magnetic depends on the spins of its atoms. The best way to think of spins is as minute bar magnets. In a crystal structure where the atoms have fixed positions in a lattice, these spins can be arranged in criss-cross fashion or aligned all in parallel like the spears of a Roman legion, depending on the individual material and its state.

Under certain conditions it is possible to generate tiny vortices within the corps of spins. These are known as skyrmions. Scientists are particularly interested in skyrmions as a key component in future technologies, such as more efficient data storage and transfer. For example, they could be used as memory bits: a skyrmion could represent the digital one, and its absence a digital zero. As skyrmions are significantly smaller than the bits used in conventional storage media, data density is much higher and potentially also more energy efficient, while read and write operations would be faster as well. Skyrmions could therefore be useful both in classical data processing and in cutting-edge quantum computing.