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Chaotic behavior is typically known from large systems: for example, from weather, from asteroids in space that are simultaneously attracted by several large celestial bodies, or from swinging pendulums that are coupled together. On the atomic scale, however, one does normally not encounter chaos—other effects predominate.

Now, for the first time, scientists at TU Wien have been able to detect clear indications of chaos on the nanometer scale—in on tiny rhodium crystals. The results have been published in the journal Nature Communications.

The chemical reaction studied is actually quite simple: with the help of a precious metal catalyst, oxygen reacts with hydrogen to form water, which is also the basic principle of a fuel cell. The reaction rate depends on external conditions (pressure, temperature). Under certain conditions, however, this reaction shows oscillating behavior, even though the external conditions are constant.

Recently, a research team led by Prof. Guo Guangcan from the University of Science and Technology of China (USTC) constructed a non-Hermiticity (NH) synthetic orbital angular momentum (OAM) dimension in a degenerate optical cavity and observed the exceptional points (EPs). This study was published in Science Advances.

In topological physics, the NH systems depict open systems with complex spectra. Exceptional points are one of the unique features of NH systems. To study EPs, the team had constructed synthetic one-dimensional lattices and established topological simulation platform in a degenerate optical cavity. Based on this platform, an additional pseudomomentum was introduced as a parameter to construct the Dirac point in the two-dimensional momentum space. A pair of EPs can be obtained by introducing non-Hermitian perturbation around the Dirac point.

The detection of complex energy spectra in NH systems can be troublesome for traditional means. The research group developed a method which is referred to as wave front angle–resolved band structure spectroscopy to investigate complex energy spectra based on synthetic OAM. Using this method, the team not only detected EPs in momentum space, but also the key features of EPs like bulk Fermi arcs, parity-time symmetry-breaking transition, energy swapping and half-integer band windings.

“Enceladus is giving us free samples of what’s hidden deep below.”

Saturn’s icy moon Enceladus shoots particles of frozen silica into space, and scientists might finally know why. Scientists have long known that Enceladus spewed out icy silica that eventually made its way into Saturn’s E ring, but they didn’t have a good explanation as to why this was happening.

Now, a new study by a team at the University of California Los Angeles might provide the answer. Their research shows that tidal heating in Encealadus’ rocky core creates currents that push the silica to the surface. Once there, it’s likely released into space by deep-sea hydrothermal vents.


NASA / jpl-caltech / space science institute.

The TOI-5205’s planetary system’s unusual “forbidden planet” is set to reveal deeper secrets of the cosmos and challenge the theories of planet formation.

Astronomers recently discovered a planet as massive as our Jupiter orbiting dwarf star called TOI 5205b. Such a sporadic cosmic occurrence led scientists to call the gas giant the “forbidden planet.” Located around 280 lightyears away from Earth, the planet was spotted with the assistance of TESS, or NASA’s Transiting Exoplanet Survey Satellite. The finding has challenged the long-held idea about the planetary system.


Carnegie Science.

The Small, Red M-dwarfs

Quantum mechanics deals with the behavior of the Universe at the super-small scale: atoms and subatomic particles that operate in ways that classical physics can’t explain.

In order to explore this tension between the quantum and the classical, scientists are constantly attempting to get larger and larger objects to behave in a quantum-like way.

Back in 2021, a team succeeded with a tiny glass nanosphere that was 100 nanometers in diameter – about a thousand times smaller than the thickness of a human hair.