Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: particle physics – Page 217

Why string theory requires extra dimensions

String theory found its origins in an attempt to understand the nascent experiments revealing the strong nuclear force. Eventually another theory, one based on particles called quarks and force carriers called gluons, would supplant it, but in the deep mathematical bones of the young string theory physicists would find curious structures, half-glimpsed ghosts, that would point to something more. Something deeper.

String claims that what we call —the point-like entities that wander freely, interact, and bind together to make up the bulk of material existence—are nothing but. Instead, there is but a single kind of fundamental object: the string. These strings, each one existing at the smallest possible limit of existence itself, vibrate. And the way those strings vibrate dictates how they manifest themselves in the larger universe. Like notes on a strummed guitar, a string vibrating with one mode will appear to us as an electron, while another vibrating at a different frequency will appear as a photon, and so on.

String theory is an audacious attempt at a theory of everything. A single mathematical framework that explains the particles that make us who and what we are along with the forces that act as the fundamental messengers among those particles. They are all, every quark in the cosmos and every photon in the field, bits of vibrating strings.

Fusion power may run out of fuel before it even gets started

For decades, achieving controlled fusion was a physics challenge. But now, as the ITER megaproject gears up to demonstrate fusion’s potential as an energy source—and startup companies race to beat it—the practical roadblocks to fusion power plants are coming into focus. One is a looming shortage of tritium fuel. Others could prevent reactors from ever running reliably—a necessity if fusion is to provide a constant “baseload” to complement intermittent solar and wind power.

Some of fusion’s fitfulness is innate to the design of doughnut-shaped tokamak reactors. The magnetic field that confines the ultrahot, energy-producing plasma is generated in part by the charged particles themselves, as they flow around the vessel. That plasma current in turn is induced by pulses of electrical current in a coil of wire in the doughnut’s hole, each lasting a few minutes at most. In between pulses the magnetic field ebbs, interrupting tokamak operations—and power delivery. The repetitive starts and stops of the reactor’s powerful magnetic fields also generate mechanical stresses that could eventually tear the machine apart.

In theory, the beams of particles and microwaves used to heat the plasma can also drive the plasma current. So can a quirk of plasma physics called the bootstrap effect. Near the edge of the plasma, a sharp pressure gradient causes the particles to spiral in such a way that they interfere with each other and push themselves—by their own bootstraps—around the ring.

Researchers demonstrate the potential of a new quantum material for creating two spintronic technologies

Over the past decade or so, physicists and engineers have been trying to identify new materials that could enable the development of electronic devices that are faster, smaller and more robust. This has become increasingly crucial, as existing technologies are made of materials that are gradually approaching their physical limits.

Antiferromagnetic (AFM) spintronics are devices or components for electronics that couple a flowing current of charge to the ordered spin ‘texture’ of specific materials. In physics, the term spin refers to the intrinsic angular momentum observed in electrons and other particles.

The successful development of AFM spintronics could have very important implications, as it could lead to the creation of devices or components that surpass Moore’s law, a principle first introduced by microchip manufacturer Gordon Earle Moore’s law essentially states that the memory, speed and performance of computers may be expected to double every two years due to the increase in the number of transistors that a microchip can contain.

An advanced computational tool for understanding quantum materials

Researchers at the University of Chicago’s Pritzker School of Molecular Engineering (PME), Argonne National Laboratory, and the University of Modena and Reggio Emilia have developed a new computational tool to describe how the atoms within quantum materials behave when they absorb and emit light.

The tool will be released as part of the open-source software package WEST, developed within the Midwest Integrated Center for Computational Materials (MICCoM) by a team led by Prof. Marco Govoni, and it helps scientists better understand and engineer new materials for quantum technologies.

“What we’ve done is broaden the ability of scientists to study these materials for quantum technologies,” said Giulia Galli, Liew Family Professor of Molecular Engineering and senior author of the paper, published in Journal of Chemical Theory and Computation. “We can now study systems and properties that were really not accessible, on a large scale, in the past.”

Mystery in the Cosmos: Telescope Array Detects Ultra-High Energy Extraterrestrial Particle With No Obvious Source

A groundbreaking detection of an extremely energetic cosmic ray by the Telescope Array experiment raises questions about its source, as it points to a cosmic void, challenging current theories in cosmic ray origins and high-energy physics.

Discovery of an Exceptional Extraterrestrial Particle

Researchers involved in the Telescope Array experiment have announced the detection of an extraordinarily energetic cosmic ray. This particle, which originated beyond our galaxy, possesses an astounding energy level of over 240 exa-electron volts (EeV). Despite this remarkable find, its exact source remains elusive, as its arrival direction does not point to any known astronomical entities.

Beyond the Void: New Experiment Challenges Quantum Electrodynamics

Absolutely empty – that is how most of us envision the vacuum. Yet, in reality, it is filled with an energetic flickering: the quantum fluctuations. Scientists are currently scientists are gearing up for a laser experiment intended to verify these vacuum fluctuations in a novel way, which could potentially provide clues to new laws in physics.

A research team from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has developed a series of proposals designed to help conduct the experiment more effectively – thus increasing the chances of success. The team presents its findings in the scientific journal Physical Review D.

The physics world has long been aware that the vacuum is not entirely void but is filled with vacuum fluctuations – an ominous quantum flickering in time and space. Although it cannot be captured directly, its influence can be indirectly observed, for example, through changes in the electromagnetic fields of tiny particles.

Magnetization by Laser Pulse: A Futuristic Twist in Material Science

A research team has revealed that ultrashort laser pulses can magnetize iron alloys, a discovery with significant potential for applications in magnetic sensor technology, data storage, and spintronics.

To magnetize an iron nail, one simply has to stroke its surface several times with a bar magnet. Yet, there is a much more unusual method: A team led by the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) discovered some time ago that a certain iron alloy can be magnetized with ultrashort laser pulses. The researchers have now teamed up with the Laserinstitut Hochschule Mittweida (LHM) to investigate this process further. They discovered that the phenomenon also occurs with a different class of materials – which significantly broadens potential application prospects. The working group presents its findings in the scientific journal Advanced Functional Materials.

Breakthrough Discovery in Magnetization.