Lifeboat Foundation

Yes, here’s the story of the dark matter hurricane — a cosmic event that may provide our first glimpse of the mysterious, invisible particle.

by

• Jackson Ryan

Researchers at the Center for Quantum Nanoscience (QNS) within the Institute for Basic Science (IBS) achieved a major breakthrough in shielding the quantum properties of single atoms on a surface. The scientists used the magnetism of single atoms, known as spin, as a basic building block for quantum information processing. The researchers could show that by packing two atoms closely together they could protect their fragile quantum properties much better than for just one atom.

The spin is a fundamental quantum mechanical object and governs magnetic properties of materials. In a classical picture, the spin often can be considered like the needle of a compass. The north or south poles of the needle, for example, can represent spin up or down. However, according to the laws of quantum mechanics, the spin can also point in both directions at the same time. This superposition state is very fragile since the interaction of the spin with the local environment causes dephasing of the superposition. Understanding the dephasing mechanism and enhancing the quantum coherence are one of the key ingredients toward spin-based quantum information processing.

In this study, published in the journal Science Advances in November 9, 2018, QNS scientists tried to suppress the decoherence of single atoms by assembling them closely together. The spins, for which they used single titanium atoms, were studied by using a sharp metal tip of a scanning tunneling microscope and the atoms’ spin states were detected using electron spin resonance. The researchers found that by bringing the atoms very close together (1 million times closer than a millimeter), they could protect the superposition states of these two magnetically coupled atoms 20 times longer compared to an individual atom.

Now scientists at the Large Hadron Collider (LHC) at Cern think they may have seen another particle, detected as a peak at a certain energy in the data, although the finding is yet to be confirmed. Again there’s a lot of excitement among particle physicists, but this time it is mixed with a sense of anxiety. Unlike the Higgs particle, which confirmed our understanding of physical reality, this new particle seems to threaten it.

The new result – consisting of a mysterious bump in the data at 28 GeV (a unit of energy) – has been published as a preprint on ArXiv. It is not yet in a peer-reviewed journal – but that’s not a big issue. The LHC collaborations have very tight internal review procedures, and we can be confident that the authors have done the sums correctly when they report a “4.2 standard deviation significance”. That means that the probability of getting a peak this big by chance – created by random noise in the data rather than a real particle – is only 0.0013%. That’s tiny – 13 in a million. So it seems like it must a real event rather than random noise – but nobody’s opening the champagne yet.

Amid the high speed cosmic rays raining down on us from the depths of space are a handful of antimatter particles called positrons.

Astronomers think that Earth is showered by these ‘anti-electrons’ because of pulsars, but there’s a weird catch – there are more of these particles coming at us than there should be. And now, thanks to a new study, we might finally get some answers.

Cosmic rays are incredibly fast particles, since they’re being shot down from space at high energies. Positrons make up a small percent of these super speedy particles, but nobody is entirely sure where or how they’re made.

Remarkable rules have been detected in the apparent chaos of disequilibrium processes. Different systems behave identically in many ways, if they belong to the same “universality class.” This means that experiments can be carried out with quantum systems that are easy to handle in order to obtain precise information about systems that cannot be directly studied in the experiment—such as the Big Bang.

Some phenomena are so complicated that it is impossible to precisely calculate them. This includes large quantum systems, which consist of many particles, particularly when they are not in an equilibrium state, but changing rapidly. Such examples include the wild particle inferno that occurs in particle accelerators when large atoms collide, or conditions just after the Big Bang, when particles rapidly expanded and then cooled.

At TU Wien and Heidelberg University, remarkable rules have been detected in the apparent chaos of disequilibrium processes. This indicates that such processes can be divided into universality classes. Systems belonging to the same class behave identically in many ways. This means that experiments can be carried out with quantum systems that are easy to handle in order to obtain precise information about other systems that cannot be directly studied in the experiment. These findings have since been published in the journal Nature.

Lattice QCD is not only teaching us how the strong interactions lead to the overwhelming majority of the mass of normal matter in our Universe, but holds the potential to teach us about all sorts of other phenomena, from nuclear reactions to dark matter.

Later today, November 7th, physics professor Phiala Shanahan will be delivering a public lecture from Perimeter Institute, and we&s;ll be live-blogging it right here at 7 PM ET / 4 PM PT. You can watch the talk right here, and follow along with my commentary below. Shanahan is an expert in theoretical nuclear and particle physics and specializes in supercomputer work involving QCD, and I&s;m so curious what else she has to say.

Continue reading “At Last, Physicists Understand Where Matter’s Mass Comes From” »

Turbulence in this sea of charged particles can interfere with satellites 🛰 as well as communication 📡 and navigation 📶 signals. When it launches tomorrow, our #NASAICON mission will watch and image airglow, helping scientists better understand the extreme variability of the region where Earth meets space.

‘’Until now, scientists assumed this all happened in a smooth, coordinated way. ‘’… silly scientists 🤔🙈🤦‍♂️.

Hitting a material with laser light sends vibrations rippling through its latticework of atoms, and at the same time can nudge the lattice into a new configuration with potentially useful properties – turning an insulator into a metal, for instance.

Until now, scientists assumed this all happened in a smooth, coordinated way. But two new studies show it doesn’t: When you look beyond the average response of atoms and vibrations to see what they do individually, the response, they found, is disorderly.

Continue reading “In materials hit with light, individual atoms and vibrations take disorderly paths” »

The kilogram is one of the most important and widely used units of measure in the world — unless you live in the US. For everyone else, having an accurate reading on what a kilogram is can be vitally important in fields like manufacturing, engineering, and transportation. Of course, a kilogram is 1,000 grams or 2.2 pounds if you want to get imperial. That doesn’t help you define a kilogram, though. The kilogram is currently controlled by a metal slug in a French vault, but its days of importance are numbered. Scientists are preparing to re define the kilogram using science.

It’s actually harder than you’d expect to know when a measurement matches the intended standard, even when it’s one of the well–define d Systéme International (SI) units. For example, the meter was originally define d in 1793 as one ten-millionth the distance from the equator to the north pole. That value was wrong, but the meter has since been re define d in more exact terms like krypton-86 wavelength emissions and most recently the speed of light in a vacuum. The second was previously define d as a tiny fraction of how long it takes the Earth to orbit the sun. Now, it’s pegged to the amount of time it takes a cesium-133 atom to oscillate 9,192,631,770 times. Again, this is immutable and extremely precise.

That brings us to the kilogram, which is a measurement of mass. Weight is different and changes based on gravity, but a kilogram is always a kilogram because it comes from measurements of density and volume. The definition of the kilogram is tied to the International Prototype of the Kilogram (IPK, see above), a small cylinder of platinum and iridium kept at the International Bureau of Weights and Measures in France. Scientists have created dozens of copies of the IPK so individual nations can standardize their measurements, but that’s a dangerous way to go about it. If anything happened to the IPK, we wouldn’t have a standard kilogram anymore.

Continue reading “Scientists Are About to Redefine the Kilogram” »