Lifeboat Foundation

Scientists have shown how three vortices can be linked in a way that prevents them from being dismantled. The structure of the links resembles a pattern used by Vikings and other ancient cultures, although this study focused on vortices in a special form of matter known as a Bose-Einstein condensate. The findings have implications for quantum computing, particle physics and other fields.

The study is published in the journal Communications Physics.

Postdoctoral researcher Toni Annala uses strings and water vortices to explain the phenomenon: “If you make a link structure out of, say, three unbroken strings in a circle, you can’t unravel it because the string can’t go through another string. If, on the other hand, the same circular structure is made in water, the water vortices can collide and merge if they are not protected.”

A concept known as “wave-particle duality” famously applies to light. But it also applies to all matter — including you.

Every proton contains three quarks: two up and one down. But charm quarks, heavier than the proton itself, have been found inside. How?

A temperature not seen since the first microsecond of the birth of the universe has been recreated by scientists, and they discovered that the event did not unfold quite the way they expected. The interaction of energy, matter, and the strong nuclear force in the ultra-hot experiments conducted at the Relativistic Heavy Ion Collider (RHIC) was thought to be well understood. However, a detailed investigation has revealed that physicists are missing something in their model of how the universe works. A recent paper detailing the findings appears in the journal Physical Review Letters.

“It’s the things you weren’t expecting that are really trying to tell you something in science,” says Steven Manly, associate professor of physics and astronomy at the University of Rochester and co-author of the paper. “The basic nature of the interactions within the hot, dense medium, or at least the manifestation of it, changes depending on the angle at which it’s viewed. We don’t know why. We’ve been handed some new pieces to the puzzle and we’re just trying to figure out how this new picture fits together.”

“They said, ‘This can’t be. You’re violating boost invariance.’ But we’ve gone over our results for more than a year, and it checks out.” —

A team of researchers from France has developed the first three-directional hybrid quantum inertial sensor, which can measure acceleration without using satellite signals. At the heart of this breakthrough device is something called “matter wave interferometry,” which uses two distinct characteristics of quantum mechanics: wave-particle duality and superposition.

In the cloud

The device consists of a cloud of rubidium atoms that are cooled to temperatures nearing absolute zero. The atoms are placed in a vacuum and are in free fall due to gravity.

Scientists are trying to work out if a strange new particle, dubbed a “ghost particle”, has been detected at CERN’s Large Hadron Collider (LHC) in Switzerland.

Using the Compact Muon Solenoid (CMS) instrument on the particle accelerator, the team said they had seen a signal that could be a particle that’s twice the mass of a carbon atom. But as the particle does not fit known theories, it could cause a bit of a stir if it exists. Their findings, which have not yet been peer-reviewed, are available on arXiv.

“I’d say theorists are excited and experimentalists are very skeptical,” Alexandre Nikitenko, a theorist on the CMS team who worked on the data, told The Guardian. “As a physicist I must be very critical, but as the author of this analysis I must have some optimism too.”

Using a chain of atoms in single-file to simulate the event horizon of a black hole, a team of physicists has observed the equivalent of what we call Hawking radiation – particles born from disturbances in the quantum fluctuations caused by the black hole’s break in spacetime.

This, they say, could help resolve the tension between two currently irreconcilable frameworks for describing the Universe: the general theory of relativity, which describes the behavior of gravity as a continuous field known as spacetime; and quantum mechanics, which describes the behavior of discrete particles using the mathematics of probability.

For a unified theory of quantum gravity that can be applied universally, these two immiscible theories need to find a way to somehow get along.

The most common particles are electrons and photons, which are understood to be examples from the great families of fermions and bosons, to which all other particles in nature belong. But there is another possible category of particles, the so-called anyons. Anyons are predicted to arise inside materials small enough to confine the electronic state wave function, as they emerge from the collective dance of many interacting electrons.

One of these is named Majorana zero mode, anyonic cousins to the Majorana fermions proposed by Ettore Majorana in 1937. Majoranas, as these hypothetical anyons are affectionally called, are predicted to exhibit numerous exotic properties, such as simultaneously behaving like a particle and antiparticle, allowing mutual annihilation, and the capability to hide quantum information by encoding it nonlocally in space. The latter property specifically holds the promise of resilient quantum computing.

Since 2010, many research groups have raced to find Majoranas. Unlike fundamental particles, such as the electron or the photon, which naturally exist in a vacuum, Majorana anyons need to be created inside hybrid materials. One of the most promising platforms for realizing them is based on hybrid superconductor-semiconductor nanodevices. Over the past decade, these devices have been studied with excruciating detail, with the hope of unambiguously proving the existence of Majoranas. However, Majoranas are tricky entities, easily overlooked or mistaken with other quantum states.

Researchers from the University of Tsukuba have shown how adding a tiny resonator structure to an ultrafast electron pulse detector reduced the intensity of terahertz radiation required to characterize the pulse duration (ACS Photonics, “Streaking of a Picosecond Electron Pulse with a Weak Terahertz Pulse”).

To study proteins—for example, when determining the mechanisms of their biological actions—researchers need to understand the motion of individual atoms within a sample. This is difficult not just because atoms are so tiny, but also because such rearrangements usually occur in picoseconds—that is, trillionths of a second.

One method to examine these systems is to excite them with an ultrafast blast of laser light, and then immediately probe them with a very short electron pulse. Based on the way the electrons scatter off the sample as a function of the delay time between the laser and electron pulses, researchers can obtain a great deal of information about the atomic dynamics. However, characterizing the initial electron pulse is difficult and requires complex setups or high-powered THz radiation.