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Archive for the ‘particle physics’ category: Page 142

Sep 16, 2023

Universe slows cosmic growth defying the theory of relativity

Posted by in categories: cosmology, particle physics

Dark energy is believed to have a negative impact on big structures, limiting the formation of such particles.

Contrary to earlier understandings based on Einstein’s theory of general relativity, research from the University of Michigan has now found that the pace of growth of these substantial structures is slower than expected.


Large cosmic structures are predicted to expand at a certain rate as the universe expands, with galaxy clusters and other dense areas expanding faster than empty space.

Continue reading “Universe slows cosmic growth defying the theory of relativity” »

Sep 16, 2023

Gearing up for mobility’s future with quantum computing

Posted by in categories: computing, particle physics, quantum physics

Any physical object, alive or inanimate, is composed of atoms and subatomic particles that interact in different ways governed by the principles of quantum mechanics. Some particles are in a pure state—they remain fixed and unchanged. Others are in a quantum state—a concept that can be difficult to understand because it involves having a particle occupy multiple states simultaneously. For instance, an electron in a pure state spins up or down; in a quantum state, also referred to as superposition, it spins up and down simultaneously. Another quantum principle states that particles can be in a state of entanglement in which changes in one directly affect the other. The principles of superposition and entanglement are fundamental to quantum computing.

Quantum bits, or qubits, are the smallest units of data that a quantum computer can process and store. In a pure state, qubits have a value of 1 or 0, similar to the bits used in computing today. In superposition, they can be both of these values simultaneously, and that enables parallel computations on a massive scale. While classical computers must conduct a new calculation any time a variable changes, quantum computers can explore a problem with many possible variables simultaneously.

Existing computers, although sufficient for many applications, can’t fully support all of the changes required to create a connected and intelligent-mobility ecosystem. Quantum computing (QC) could potentially provide faster and better solutions by leveraging the principles of quantum mechanics—the rules that govern how atoms and subatomic particles act and interact. (See sidebar, “Principles of quantum computing,” for more information). Over the short term, QC may be most applicable to solving complex problems involving small data sets; as its performance improves, QC will be applied to extremely large datasets.

Sep 15, 2023

Whirlwind Tech: The Future of Energy-Efficient Spintronics Computing

Posted by in categories: computing, particle physics, sustainability

Researchers in Germany and Japan have been able to increase the diffusion of magnetic whirls, so-called skyrmions, by a factor of ten.

In today’s world, our lives are unimaginable without computers. Up until now, these devices process information using primarily electrons as charge carriers, with the components themselves heating up significantly in the process. Active cooling is thus necessary, which comes with high energy costs. Spintronics aims to solve this problem: Instead of utilizing the electron flow for information processing, it relies on their spin or their intrinsic angular momentum. This approach is expected to have a positive impact on the size, speed, and sustainability of computers or specific components.

Magnetic whirls store and process information.

Sep 15, 2023

AI and atoms: How artificial intelligence is revolutionizing nuclear material

Posted by in categories: particle physics, robotics/AI

There’s a three-dimensional solution to manage the evolving dual-use concern of AI: advance states-centric monitoring and regulation, promote intellectual exchange between the non-proliferation sector and the AI industry, and encourage AI industrial contributions.

Sep 15, 2023

Student-built nuclear fusion reactor to debut in Australia

Posted by in categories: nuclear energy, particle physics

The student-built Tokamak reactor will be 3 × 3 feet in size and be the first such facility built for nuclear fusion in a university.

Australia is set to become home to the world’s first nuclear fusion facility designed, built, and operated by students. The project is planned by the University of New South Wales (UNSW) but will not use nuclear fuel, a press release said.

Nuclear fusion is the process where atoms of lighter elements like hydrogen are heated up to hundreds of millions of degrees Celsius to enable their fusion under large amounts of force. The process releases large amounts of energy, which can then be used to power devices and machines.

Sep 15, 2023

Matter found to comprise 31% of the total amount of matter and energy in the universe

Posted by in categories: cosmology, economics, particle physics

One of the most interesting and important questions in cosmology is, “How much matter exists in the universe?” An international team, including scientists at Chiba University, has now succeeded in measuring the total amount of matter for the second time. Reporting in The Astrophysical Journal, the team determined that matter makes up 31% of the total amount of matter and energy in the universe, with the remainder consisting of dark energy.

“Cosmologists believe that only about 20% of the total is made of regular or ‘baryonic’ matter, which includes stars, galaxies, atoms, and life,” explains first author Dr. Mohamed Abdullah, a researcher at the National Research Institute of Astronomy and Geophysics-Egypt, Chiba University, Japan. “About 80% is made of , whose mysterious nature is not yet known but may consist of some as-yet-undiscovered subatomic particles.”

“The team used a well-proven technique to determine the total amount of matter in the universe, which is to compare the observed number and mass of galaxy clusters per unit volume with predictions from ,” says co-author Gillian Wilson, Abdullah’s former graduate advisor and Professor of Physics and Vice Chancellor for research, innovation, and economic development at UC Merced.

Sep 15, 2023

Rare-earth atom can make a quantum repeater at telecom wavelengths

Posted by in categories: particle physics, quantum physics

Demonstration with erbium marks a step towards long-distance quantum communication.

Sep 15, 2023

Scientists Discover “Demon” Particle

Posted by in categories: materials, particle physics

Right in time for spooky season, scientists have discovered the existence of something called the “demon” particle. While the name of the material may strike terror in some, its discovery is actually far less sinister. Hidden from researchers for over seven decades, the “composite” of electrons was recently discovered according to a new study published in Nature.

“Demons have been theoretically conjectured for a long time, but experimentalists never studied them,” paper senior author Peter Abbamonte said in the study. “In fact, we weren’t even looking for it. But it turned out we were doing exactly the right thing, and we found it.”

Sep 14, 2023

A scalable and user-friendly platform for physicists to carry out advanced quantum experiments, cheaply

Posted by in categories: computing, particle physics, quantum physics

Quantum computers can solve certain computational problems much faster than ordinary computers by using specific quantum properties. The basic building blocks of such machines are called quantum-bits or qubits. Qubits can be realized using several physical platforms such as nuclear spins, trapped ions, cold atoms, photons, and using superconducting Josephson circuits.

Several such qubits operate in the domain, and require specialized room temperature microwave electronics for control and readout of the quantum states of the qubits. However, there lies a challenge when it comes to connecting classical electronics to these qubits. The qubits need high frequency (GHz) electromagnetic signals for control and readout pulses in the order of a few tens of nanoseconds.

The traditional setup for generation and capture of such signals is often costly and complex with many components. This can be addressed by developing a specific FPGA-based system that brings the functionality of all the traditional equipment on to a single board. However, with such developments, three main challenges need to be kept in mind: generation and capture of the high-fidelity microwave signals, scalability, and a user-friendly interface.

Sep 14, 2023

Toward a Complete Theory of Crystal Vibrations

Posted by in categories: computing, information science, mathematics, particle physics

A new set of equations captures the dynamical interplay of electrons and vibrations in crystals and forms a basis for computational studies.

Although a crystal is a highly ordered structure, it is never at rest: its atoms are constantly vibrating about their equilibrium positions—even down to zero temperature. Such vibrations are called phonons, and their interaction with the electrons that hold the crystal together is partly responsible for the crystal’s optical properties, its ability to conduct heat or electricity, and even its vanishing electrical resistance if it is superconducting. Predicting, or at least understanding, such properties requires an accurate description of the interplay of electrons and phonons. This task is formidable given that the electronic problem alone—assuming that the atomic nuclei stand still—is already challenging and lacks an exact solution. Now, based on a long series of earlier milestones, Gianluca Stefanucci of the Tor Vergata University of Rome and colleagues have made an important step toward a complete theory of electrons and phonons [1].

At a low level of theory, the electron–phonon problem is easily formulated. First, one considers an arrangement of massive point charges representing electrons and atomic nuclei. Second, one lets these charges evolve under Coulomb’s law and the Schrödinger equation, possibly introducing some perturbation from time to time. The mathematical representation of the energy of such a system, consisting of kinetic and interaction terms, is the system’s Hamiltonian. However, knowing the exact theory is not enough because the corresponding equations are only formally simple. In practice, they are far too complex—not least owing to the huge number of particles involved—so that approximations are needed. Hence, at a high level, a workable theory should provide the means to make reasonable approximations yielding equations that can be solved on today’s computers.