Scientists are diving into the deep sea to study one of the universe’s biggest mysteries—quantum gravity.
Using KM3NeT, a vast underwater neutrino telescope, researchers are watching ghost-like particles that may hold the key to uniting the physics of the very large and the very small. By analyzing how neutrinos oscillate—or don’t—during their journey through space, they’re searching for subtle signs of decoherence, a possible effect of quantum gravity.
A tiny particle and a big physics puzzle.
In the 1930s, researchers first noticed oddities in how galaxies moved, suggesting something invisible exerted gravitational pull. Decades later, studies of the cosmic microwave background —the lingering radiation from the universe’s birth—confirmed dark matter’s importance in shaping cosmic evolution.
A pivotal study by the Planck Collaboration in 2018 revealed that dark matter makes up roughly 27% of the universe’s total energy. By comparison, ordinary matter—the stuff of planets, stars, and us—accounts for only 5%.
Scientists have spent decades trying to understand what dark matter might be. Supersymmetry, a popular theory in particle physics, proposes a “partner” particle for every known particle, potentially offering clues about dark matter’s identity.
In a new development at CERN, researchers at the LHCb collaboration have determined the spin-parity of singly heavy charm baryons for the first time, addressing a long-standing mystery in baryon research.
Singly heavy baryons are particles containing one heavy quark—which in this case is a charm quark—and two light quarks. While the existence of these particles is not new, the exact nature of their excitation modes has remained elusive.
The study, published in Physical Review Letters, determined the nature by measuring the spin-parity of these charm baryons. Phys.org spoke to co-author Guanyue Wan, a Ph.D. Candidate at Peking University, China.
For the first time, scientists have directly measured the cross-section of a weak r-process nuclear reaction using a radioactive ion beam. Specifically, the team studied the reaction 94Sr(α, n)97Zr, where a radioactive isotope of strontium (strontium-94) absorbs an alpha particle (a helium nucleus), emits a neutron, and becomes zirconium-97.
The findings have been published as an Editors’ Suggestion in Physical Review Letters
<em> Physical Review Letters (PRL)</em> is a prestigious peer-reviewed scientific journal published by the American Physical Society. Launched in 1958, it is renowned for its swift publication of short reports on significant fundamental research in all fields of physics. PRL serves as a venue for researchers to quickly share groundbreaking and innovative findings that can potentially shift or enhance understanding in areas such as particle physics, quantum mechanics, relativity, and condensed matter physics. The journal is highly regarded in the scientific community for its rigorous peer review process and its focus on high-impact papers that often provide foundational insights within the field of physics.
Quantum technologies operate by leveraging various quantum mechanical effects, including entanglement. Entanglement occurs when two or more particles share correlated states even if they are distant.
When two particles are spin entangled, the intrinsic angular momentum (i.e., spin) of one particle can influence that of its entangled partner. This would suggest that the energy of the second particle can be altered via a nonlocal correlation, without enabling faster-than-light communication.
Researchers at Shanghai Jiao Tong University and Hefei National Laboratory recently carried out a study aimed at testing this theoretical prediction experimentally using two quantum memories.
A group of Carnegie Mellon University researchers recently devised a method allowing them to create large amounts of a material required to make two-dimensional (2D) semiconductors with record high performance. Their paper, published in ACS Applied Materials & Interfaces in late December 2024, could lead to more efficient and tunable photodetectors, paving the way for the next generation of light-sensing and multifunctional optoelectronic devices.
“Semiconductors are the key enabling technology for today’s electronics, from laptops to smartphones to AI applications,” said Xu Zhang, assistant professor of electrical and computer engineering. “They control the flow of electricity, acting as a bridge between conductors (which allow electricity to flow freely) and insulators (which block it).”
Zhang’s research group wanted to develop a certain kind of photodetector, a device capable of detecting light and which can be used in a variety of applications. To create this photodetector, the group needed to use materials that were an atom’s-width thick, or as close to 2D as is possible.
A research team led by Professor Sun Qing-Feng in collaboration with Professor He Lin’s research group from Beijing Normal University has achieved orbital hybridization in graphene-based artificial atoms for the first time.
Their study, titled “Orbital hybridization in graphene-based artificial atoms” has been published in Nature. The work marks a significant milestone in the field of quantum physics and materials science, bridging the gap between artificial and real atomic behaviors.
Quantum dots, often called artificial atoms, can mimic atomic orbitals but have not yet been used to simulate orbital hybridization, a crucial process in real atoms. While quantum dots have successfully demonstrated artificial bonding and antibonding states, their ability to replicate orbital hybridization remained unexplored.
A study led by the University of Portsmouth has achieved unprecedented precision in detecting tiny shifts in light displacements at the nanoscale. This is relevant in the characterization of birefringent materials and in high-precision measurements of rotations.
The quantum sensing breakthrough is published in the journal Physical Review A, and has the potential to revolutionize many aspects of daily life, industry, and science.
Imagine two photons, massless particles of light, that are intertwined in a unique way, meaning their propagation is connected even when they are separated. When these photons pass through a device that splits the particles of light into two paths—known as a beam-splitter—they interfere with each other in special patterns. By analyzing these patterns, researchers have developed a highly precise method to detect even the tiniest initial spatial shifts between them.