Wednesday Apr. 4, 2018 at 7 PM ET
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From the Stone Age to the Silicon Age, nothing has had a more profound influence on the world than our understanding of the materials around us. The Industrial Revolution of the 19th century and the Information Revolution of the 20th were fueled by humankind’s ability to understand, harness, and control materials.
Today, our IBM Research team published the first real world demonstration of a rocking Brownian motor for nanoparticles in the peer-review journal Science. The motors propel nanoscale particles along predefined racetracks to enable researchers to separate nanoparticle populations with unprecedented precision. The reported findings show great potential for lab-on-a-chip applications in material science, environmental sciences or biochemistry.
No More Fairy Tales
Do you remember the Grimm version of Cinderella when she had to pick peas and lentils out of the ashes? Now imagine that instead of peas and lentils you have a suspension of nanoparticles, which are only 60 nanometer (nm) and 100 nm in size — that’s 1,000 times smaller than the diameter of a human hair. Using previous methods, one could separate them with a complicated filter or machines, however these are too bulky and complex to be integrated into a handheld lab-on-a-chip.
Physicists in Switzerland are on a subatomic hunt that, they hope, will reveal some entirely new results beyond the limits of their theories.
An experiment at CERN in Geneva, called NA62, is designed to let scientists watch a rare kind of particle decay. The team, using a whole new method, may have finally spotted what they’re looking for.
You’ve probably heard of quarks, the building blocks of other subatomic particles. There are six: the common up and down quark, the strange and charm quarks, and the rarest top and bottom quarks. Protons and neutrons contain only up and down quarks.
Shortly after learning he’d won the Nobel Prize in physics, Richard Taylor stared at his reflection in a mirror.
“Murray Gell-Mann is smart. Dick Garwin is smart,” he told himself, referring to two pioneering 20th century physicists. “You are lucky.”
The self-effacing Taylor, a Stanford University professor emeritus of physics who shared the Nobel in 1990 for his role in the discovery of quarks, died Feb. 22 at his home on the Stanford campus. He was 88.
Millions of light-years from Earth, there’s a galaxy that is completely devoid of dark matter — the mysterious, unseen material that is thought to permeate the Universe. Instead, the galaxy seems to be made up of just regular ol’ matter, the kind that comprises stars, planets, and dust. That makes this galaxy a rare find, and its discovery opens up new possibilities for how dark matter is distributed throughout the cosmos.
No one knows what dark matter is. True to its name, the material doesn’t emit light, so we’ve never detected it directly. All scientists know is that it’s out there based on their observations of how galaxies and stars move. Some unseen substance is affecting these deep-space objects, filling up the space between stars and clusters of galaxies. And there seems to be a lot of it. Dark matter is thought to make up 27 percent of all the mass and energy of the Universe. The matter we can see — the atoms that make up you and me — accounts for just 5 percent.
This past June, 500 pounds of a specially fabricated crystal buried in an Italian mountain seemed to glow just a little brighter. It wasn’t the first time, nor the last—every year, the signal seems to increase and decrease like clockwork as the Earth orbits the Sun.
Some people think the crystal has spotted a signature of elusive dark matter particles.
Scientists from an Italian experiment called DAMA/LIBRA announced at the XLIX meeting of the Gran Sasso Scientific Committee that after another six years observing, the annual modulation of their crystal’s signal is still present. This experiment was specially built to detect dark matter, and indeed, DAMA/LIBRA’s scientists are convinced they’ve spotted the elusive dark matter particle. Others are more skeptical.
Out of billions of stars in the Milky Way galaxy, there’s one in particular, orbiting 25,000 light-years from the galactic core, that affects Earth day by day, moment by moment. That star, of course, is the sun. While the sun’s activity cycle has been tracked for about two and a half centuries, the use of space-based telescopes offers a new and unique perspective of our nearest star.
The Solar and Heliospheric Observatory (SOHO), a collaboration between NASA and the European Space Agency (ESA), has been in space for more than 22 years — the average length of one completed solar magnetic cycle, according to an image caption from ESA. In the new image, SOHO researchers pulled together 22 images of the sun, taken each spring over the course of a full solar cycle. When the sun is at its most active, strong magnetic fields show up as bright spots in the sun’s outer atmosphere, called the corona; black sunspots appear as concentrations of magnetic fields reduce the sun’s surface temperature during active periods as well.
Throughout the sun’s magnetic cycles, the polarity of the sun’s magnetic field gradually flips. This initial phase takes 11 years, and after another 11 years, the magnetic field’s orientation returns to where it began. Monitoring the entire 22-year cycle provided significant data regarding the interaction between the sun’s activity and Earth, improved space-weather forecasting capabilities and more, ESA officials said in the caption. SOHO has revealed much about the sun itself, capturing “sunquakes,” discovering waves traveling through the corona and collecting details about the charged particles it propels into space, called the solar wind.
Researchers at Griffith University working with Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) have unveiled a stunningly accurate technique for scientific measurements which uses a single atom as the sensor, with sensitivity down to 100 zeptoNewtons.
Using highly miniaturised segmented-style Fresnel lenses — the same design used in lighthouses for more than a century — which enable exceptionally high-quality images of a single atom, the scientists have been able to detect position displacements with nanometre precision in three dimensions.
“Our atom is missing one electron, so it’s very sensitive to electrical fields. By measuring the displacement, we’ve built a very sensitive tool for measuring electrical forces.” Dr Erik Streed, of the Centre for Quantum Dynamics, explained.
Scientists have used the same technology that brought us time crystals to create a room-temperature maser—a microwave laser—that overcomes many of masers’ past problems.
Masers predate lasers. They’re pretty much the same thing, but masers shoot out microwave light instead of visible or infrared light. Lasers have always been more popular, since masers have only worked in short pulses and required incredibly cold temperatures and vacuums to operate. But now, a team of scientists in the United Kingdom has overcome both old and new challenges to debut their continuously emitting, room-temperature maser. Their research was published this week in Nature.
Masers and lasers operate on basically the same principle. Atoms typically have electrons orbiting their nuclei in specific energy levels. Add some energy in the form of, say, a photon, and the electrons jump to higher energy levels. Pump enough of those electrons into the same higher energy level, and you can release a cascade of photons of the same color (or wavelength, in physics speak) whose waves line up.