SuperAgers retain memory performance in their 80s and 90s, which new research has shown is not just due to low genetic Alzheimer’s risk.
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Quantum computer boldly goes where no quantum computer has gone before: Space
There’s big news from the quantum world. A quantum computer has been used in space for the first time. The device was aboard a spacecraft in low Earth orbit and demonstrated technology that could eventually help solve a problem that has been bugging satellites for years.
The issue is that when orbiting satellites send their raw data back down to Earth, bottlenecks and bandwidth limits slow everything down. One way to overcome this would be to process the raw data in situ before sending it.
So a team of physicists led by Philip Walther at the University of Vienna came up with a way that could eventually do just that. Their solution was to build a quantum photonic processor that uses individual light particles, or photons, to perform complex operations using compact optical hardware.
DarkSide detector puts ‘nuclear’ dark matter to the test
Researchers at the DarkSide collaboration have unveiled results from a seven-year experiment that tested whether dark matter particles could exist as composites of smaller, elementary particles. While the search turned up no direct evidence of this “ultraheavy nuclear” dark matter, results from the DarkSide-50 detector could lay the groundwork for future experiments, helping physicists work out whether dark matter has an internal structure.
The research has been published in Physical Review D.
A tiny stellar system may be a ‘satellite of a satellite’
Astronomers using data from the Euclid space telescope have discovered an exceptionally faint stellar system near the Fornax dwarf galaxy. Called Fornax-7, it appears to contain only about 170 times the mass of the sun in stars. The discovery paper was posted to the arXiv preprint server on Sept. 13.
The lambda cold dark matter model of the universe predicts that dark matter halos of any mass should host their own smaller subhalos. This is well established for galaxies with masses similar to the Milky Way’s, which have many dwarf satellites, but it has never been confirmed for hosts much less massive than the Milky Way.
The current record-holder is the Large Magellanic Cloud (LMC), which has candidate ultra-faint companions. Finding a satellite around something as small as the Fornax dwarf spheroidal galaxy (Fornax dSph), roughly 100 times less massive than the LMC, would extend “the observed hierarchical formation of satellite systems nearly two orders of magnitude below the LMC,” researchers write in the paper.
Magnetic order survives weak quantum fluctuations in gapless magnets
In a new study published in Physical Review Letters, researchers have shown that magnetic order can survive weak quantum fluctuations in disordered magnets that lack an energy gap. The work establishes robust ferromagnetism in the two-dimensional random-bond quantum Ising model, confirming a longstanding conjecture in quantum statistical mechanics.
Many magnets owe their order to spontaneous symmetry breaking (SSB). Physicists have long sought to prove that this order is stable against perturbations such as quantum fluctuations. Existing proofs, however, typically require the system to have an energy gap. Disordered magnets such as the random-bond Ising model are gapless, placing them outside the reach of these proofs.
The researchers developed a proof technique that does not rely on an energy gap. They adapted an argument from statistical mechanics, known as the Peierls argument, to quantum systems.
New tool tracks a hidden protein involved in viral infection and cell cleanup
Viruses such as influenza A and dengue can hijack a cellular system that helps manage protein aggregates. Previous work by FMI emeritus group leader Patrick Matthias and his team showed that a small protein called ubiquitin plays an important role in this process.
The viruses rely on a free form of ubiquitin that is not attached to other proteins. This “unanchored” ubiquitin is also involved in immune responses and protein cleanup, but it has been difficult to study because researchers lack tools that can specifically detect it.
So, Matthias and collaborators at ETH Zurich set out to build a tool that could distinguish unanchored ubiquitin from other forms of the protein. Working with researchers in Guillaume Diss’s lab and the FMI structural biology facility, Longlong Wang—a former postdoc with Matthias—started with HDAC6, a protein that naturally binds unanchored ubiquitin. They improved the binding, then used computer-based protein design tools, including AlphaFold, to generate thousands of new versions. Their work is published in Science Advances.
Scientists find lunar ‘magnetic fossil’ in Chang’e-6 samples
The moon no longer has a global magnetic field, but lunar rocks and soils still contain records of ancient magnetism. Studying the magnetic minerals in these samples can help scientists understand how the moon’s magnetic field evolved over time.
Researchers examining impact-glass particles containing metallic iron from Chang’e-6 lunar soil samples discovered face-centered cubic γ-Fe—the first time this iron phase has been identified in natural lunar samples.
The study, led by professor Du Haifeng from the High Magnetic Field Laboratory of the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS), was published in the Proceedings of the National Academy of Sciences on Sept. 16.
Spin rephasing helps quantum memories store single-photon states longer for future networks
We are continuously sending information to each other, transmitting zeros and ones through a giant network of connected computers and devices. Scientists are now trying to extend this familiar concept of the internet to the quantum realm, looking for an efficient way to exchange quantum rather than classical information: qubits instead of bits. The motivation is not just scientific curiosity. Qubits can be a 0, a 1 or any superposition of the two. They can also become entangled, showing a degree of correlation that is out of reach for classical bits.
A key element in enabling the quantum internet is the quantum repeater, an architecture aimed at distributing entanglement over long distances. Quantum repeaters, in turn, require quantum memories that can hold a quantum state long enough to synchronize measurements across different network segments and establish entanglement.
ICFO researchers Alberto Rodríguez Moldes, Dr. Félicien Appas, Jonathan Hänni, Dr. Jelena Rakonjac and Dr. Samuele Grandi, led by ICREA professor Hugues de Riedmatten, have taken a significant step in this direction. By implementing the so-called spin rephasing protocol, they have demonstrated that solid-state quantum memories—promising candidates for building quantum networks because of their proven high efficiency, capacity to store entanglement and multiplexing features—can store single photons for longer than previously possible. The results, published in Physical Review Letters and obtained within the Quantum Internet Alliance (QIA), bring us closer to the quantum internet.
Laser temporarily reprograms ultrathin optical device without electrodes
A tiny device that can be reprogrammed using a laser could lead to adaptable devices for computing, imaging and telecommunications. Most devices are built to perform a particular job. If you want them to do something different, you generally need to replace a component, rewire the system or manufacture a new one. For example, every time you ask a large language model like ChatGPT or Claude a question, many electrical signals race through computer chips, carrying information and performing calculations. This takes energy, and lots of it.
Scientists are always searching for faster and potentially more energy-efficient ways to process information. One possible solution is to replace some electrical signals with light.
An international team of researchers led by the ARC Center for Transformative Meta-Optical Systems (TMOS) at The Australian National University combined an ultrathin optical surface with liquid crystals, the material used in many electronic displays. The team collaborated with researchers at Nottingham Trent University in the U.K. and Friedrich Schiller University Jena in Germany.