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Scientists claim they have observed a fifth force of nature that could transform our understanding of how the universe works.

Researchers at the Hungarian Academy of Sciences have revealed results that could show it in action.

They saw an excited, decaying helium atom emit light when the particles split in a strange way that could not be explained by the current understanding of physics.

The cosmos was born in a churning fluid 300 million times hotter than the sun. We’ve recreated this hell, and it’s not just hot, it is also very, very strange, says Amanda Gefter (science writer based in London). TO LOOK deep into the fundamental structure of matter is to look billions of years back in time, to the moment when matter first blinked into being. Recreating the conditions of that moment has long been an aim for physicists wanting to understand how the universe evolved from the cosmic fireball that existed a fraction of a second after the big bang. Now researchers at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in Upton, New York, have, almost certainly, finally recreated the moments after creation. By colliding nuclei together at enormous speeds, RHIC experimenters were able to break down the structure of nuclear matter. This resulted, most experts agree, in the formation of a long-sought-after plasma that is believed to be the primal stuff of the cosmos, the state of matter at the beginning of time. It turns out, though, that the nature of matter is inextricably tied to the vacuum in which it resides. And the RHIC experiments have thrown up some surprises. They seem to show that the vacuum is a richer and more complicated place than was previously imagined. They suggest the boundary between something and nothing is more blurred than experts had predicted. The stuff made at RHIC is a plasma consisting of quarks and gluons, the most basic building blocks of everything we see around us. Quarks combine in threes to form the protons and neutrons that comprise the nucleus of every atom. But while we can observe a single proton or neutron, we cannot observe a single quark. Quarks are perpetually confined to group living. In fact, the harder you try to pull quarks apart, the stronger the force between them becomes. This is part of the theory of quantum chromodynamics (QCD), which describes how the force between the quarks is carried by the massless gluons.

In QCD, it is the vacuum that imprisons the quarks. While it may sound like a barren place, the vacuum of QCD is a complex, dynamic arena. It writhes with virtual particles that appear in pairs, then annihilate and disappear again. It is haunted by strange creatures of various kinds, too, topologically complex knots and twists that are relatives of wormholes, places where space turns in on itself and seems treacherous. These knots and twists carve out paths for the gluons to travel along, thereby keeping the quarks together. These strange ideas have credence because of the success of QCD in predicting the reactions of fundamental particles. The only way to unglue quarks is to “melt” the vacuum between them. But the vacuum doesn’t give in easily. To raze its jagged terrain requires enormous amounts of concentrated energy, found only in powerful nuclear collisions, or the fireball at the earliest moments of time.

Scientists from Regensburg and Zurich have found a fascinating way to push an atom with controlled forces so quickly that they can choreograph the motion of a single molecule within less than a trillionth of a second. The extremely sharp needle of their unique ultrafast microscope serves as the technical basis: It carefully scans molecules, similar to a record player. Physicists at the University of Regensburg now showed that shining light pulses onto this needle can transform it into an ultrafast “atomic hand.” This allows molecules to be steered—and new technologies can be inspired.

Atoms and are the constituents of virtually all matter that surrounds us. Interacting with each other according to the rules of quantum mechanics, they form complex systems with an infinite variety of functions. To examine , in a cell, or new ways of solar energy harvesting, scientists would love to not only observe individual molecules, but even control them.

Most intuitively, people learn by haptic exploration, such as pushing, pulling, or tapping. Naturally, we are used to macroscopic objects that we can directly touch, squeeze or nudge by exerting forces. Similarly, atoms and molecules interact via forces, but these forces are extreme in multiple respects. First, the forces acting between atoms and molecules occur at extremely small lengths. In fact, these objects are so small that a special length scale has been introduced to measure them: 1 Ångström (1Å = 0.000,000,000,1 m). Second, at the same time, atoms and molecules move and wiggle around extremely fast. In fact, their motion takes place faster than picoseconds (1 ps = 0.000,000,000,001 s). Hence, to directly steer a molecule during its motion, a tool is required to generate ultrafast forces at the atomic scale.

Scientists on an experiment at the Large Hadron Collider see massive W particles emerging from collisions with electromagnetic fields. How can this happen?

The Large Hadron Collider plays with Albert Einstein’s famous equation, E = mc², to transform matter into energy and then back into different forms of matter. But on rare occasions, it can skip the first step and collide pure energy—in the form of electromagnetic waves.

Last year, the ATLAS experiment at the LHC observed two photons, particles of light, ricocheting off one another and producing two new photons. This year, they’ve taken that research a step further and discovered photons merging and transforming into something even more interesting: W bosons, particles that carry the weak force, which governs nuclear decay.

At these temperatures, the atoms move extremely slowly and can be controlled through quantum mechanical effects that are negligible at higher temperatures.

The team used lasers to excite the atoms and coax them into one shared motion. They found that when the atoms act collectively, they can shape and steer light through their electrical and magnetic interactions with it. The shared behavior allows them to act like a collection of electric charges or very small magnets that affect the light.

New experimental evidence of a collective behavior of electrons to form “quasiparticles” called “anyons” has been reported by a team of scientists at Purdue University.

Anyons have characteristics not seen in other , including exhibiting fractional charge and fractional statistics that maintain a “memory” of their interactions with other quasiparticles by inducing quantum mechanical phase changes.

Postdoctoral research associate James Nakamura, with assistance from research group members Shuang Liang and Geoffrey Gardner, made the discovery while working in the laboratory of professor Michael Manfra is a Distinguished Professor of Physics and Astronomy, Purdue’s Bill and Dee O’Brien Chair Professor of Physics and Astronomy, professor of electrical and computer engineering, and professor of materials engineering. Although this work might eventually turn out to be relevant to the development of a quantum computer, for now, Manfra said, it is to be considered an important step in understanding the physics of quasiparticles.

The technology behind the quantum computers of the future is fast developing, with several different approaches in progress. Many of the strategies, or “blueprints,” for quantum computers rely on atoms or artificial atom-like electrical circuits. In a new theoretical study in the journal Physical Review X, a group of physicists at Caltech demonstrates the benefits of a lesser-studied approach that relies not on atoms but molecules.

“In the quantum world, we have several blueprints on the table and we are simultaneously improving all of them,” says lead author Victor Albert, the Lee A. DuBridge Postdoctoral Scholar in Theoretical Physics. “People have been thinking about using molecules to encode information since 2001, but now we are showing how molecules, which are more complex than atoms, could lead to fewer errors in quantum computing.”

At the heart of quantum computers are what are known as qubits. These are similar to the bits in classical computers, but unlike classical bits they can experience a bizarre phenomenon known as superposition in which they exist in two states or more at once. Like the famous Schrödinger’s cat thought experiment, which describes a cat that is both dead and alive at the same time, particles can exist in multiple states at once. The phenomenon of superposition is at the heart of quantum computing: the fact that qubits can take on many forms simultaneously means that they have exponentially more computing power than classical bits.

Solar flares emit sudden, strong bursts of electromagnetic radiation from the Sun’s surface and its atmosphere, and eject plasma and energetic particles into inter-planetary space. Since large solar flares can cause severe space weather disturbances affecting Earth, to mitigate their impact their occurrence needs to be predicted. However, as the onset mechanism of solar flares is unclear, most flare prediction methods so far have relied on empirical methods.

The research team led by Professor Kanya Kusano (Director of the Institute for Space-Earth Environmental Research, Nagoya University) recently succeeded in developing the first physics-based model that can accurately predict imminent large solar flares. The work was published in the journal Science on July 31, 2020.

The new method of flare prediction, called the kappa scheme, is based on the theory of “double-arc instability,” that is a magnetohydrodynamic (MHD) instability triggered by magnetic reconnection. The researchers assumed that a small-scale reconnection of magnetic field lines can form a double-arc (m-shape) magnetic field and trigger the onset of a solar flare (Figure 1). The kappa scheme can predict how a small magnetic reconnection triggers a large flare and how a large solar flare can occur.

Picture an airplane that can only climb to one or two altitudes after taking off. That limitation would be similar to the plight facing scientists who seek to avoid instabilities that restrict the path to clean, safe, and abundant fusion energy in doughnut-shaped tokamak facilities. Researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and General Atomics (GA) have now published a breakthrough explanation of this tokamak restriction and how it may be overcome.

Toroidal, or doughnut-shaped, tokamaks are prone to intense bursts of heat and particles, called edge localized modes (ELMs). These ELMs can damage the reactor walls and must be controlled to develop reliable fusion power. Fortunately, scientists have learned to tame these ELMs by applying spiraling rippled magnetic fields to the surface of the plasma that fuels fusion reactions. However, the taming of ELMs requires very specific conditions that limit the operational flexibility of tokamak reactors.