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A new manipulation technique could enable the realization of more versatile quantum simulators.

The Born rule, formulated almost a century ago, says that measuring a system yields an outcome whose probability is determined by the wave-function amplitude. As if by magic, preparing a quantum system in the same way and performing the same measurement can produce different results. For a long time, the Born rule’s probabilistic nature was more of a theoretical concept. But with the advent of quantum simulators, it has become an experimental reality. So-called snapshots—different measurement outcomes of the same quantum many-body state—are routinely measured. In the case of cold atoms in optical lattices, such snapshots are images that show with single-site resolution whether an atom is present or not. Now Alexander Impertro of the Ludwig Maximilian University of Munich and his collaborators have devised a way to take snapshots not just of atoms’ whereabouts but also of properties analogous to currents and local kinetic energy in crystals [1].

Imagine the possibility of sending messages that are completely impervious to even the most powerful computers. This is the incredible promise of quantum communication, which harnesses the unique properties of light particles known as photons.

Contrary to widespread belief, our Moon does have an atmosphere, albeit extremely thin and officially known as an “exosphere”. But what are the processes responsible for forming and maintaining this exosphere, which have eluded scientists for some time? This is what a recent study published in Science Advances hopes to address as a team of researchers investigated how a phenomenon known as “impact vaporization” from the surface being hit my objects ranging from micrometeoroids to massive meteorites during its recent and ancient history, respectively. This study holds the potential to help scientists better understand the formation and evolution of planetary bodies throughout the solar system and the processes that maintain them today.

For the study, the team analyzed 10 Apollo lunar samples (one volcanic and nine lunar regolith aka “lunar soil”) collected by astronauts over five landing sites with the goal of ascertaining how much space weathering they’ve endured over the Moon’s long history. This is because when an impact occurs, this causes the specific atoms to vaporize and kick up portions of this material into space while other portions remain trapped by lunar gravity, although now orbiting the Moon. In the end, the researchers discovered that impact vaporization is the main process responsible for the lunar exosphere over the several billion-year history of the Moon.

“We give a definitive answer that meteorite impact vaporization is the dominant process that creates the lunar atmosphere,” said Dr. Nicole Nie, who is an assistant professor in MIT’s Department of Earth, Atmospheric, and Planetary Sciences and lead author of the study. “The moon is close to 4.5 billion years old, and through that time the surface has been continuously bombarded by meteorites. We show that eventually, a thin atmosphere reaches a steady state because it’s being continuously replenished by small impacts all over the moon.”

TAIPEI, Taiwan — Chinese-American physicist Tsung-Dao Lee, who in 1957 became the second-youngest scientist to receive a Nobel Prize, died Sunday at his home in San Francisco at age 97, according to a Chinese university and a research center.

Lee, whose work advanced the understanding of particle physics, was one of the great masters in the field, according to a joint obituary released Monday by the Tsung-Dao Lee Institute at Shanghai Jiao Tong University and the Beijing-based China Center for Advanced Science and Technology.

Lee, a naturalized U.S. citizen since 1962, was also a professor emeritus at Columbia University in New York.

Researchers at the University of Cologne have achieved a significant breakthrough in quantum materials, potentially setting the stage for advancements in topological superconductivity and robust quantum computing / publication in Nature Physics.

A team of experimental physicists led by the University of Cologne have shown that it is possible to create superconducting effects in special materials known for their unique edge-only electrical properties. This discovery provides a new way to explore advanced quantum states that could be crucial for developing stable and efficient quantum computers. Their study, titled ‘Induced superconducting correlations in a quantum anomalous Hall insulator’, has been published in Nature Physics.

Superconductivity is a phenomenon where electricity flows without resistance in certain materials. The quantum anomalous Hall effect is another phenomenon that also causes zero resistance, but with a twist: it is confined to the edges rather than spreading throughout. Theory predicts that a combination of superconductivity and the quantum anomalous Hall effect will give rise to topologically-protected particles called Majorana fermions that will potentially revolutionize future technologies such as quantum computers. Such a combination can be achieved by inducing superconductivity in the edge of a quantum anomalous Hall insulator that is already resistance-free. The resultant chiral Majorana edge state, which is a special type of Majorana fermions, is a key to realizing ‘flying qubits’ (or quantum bits) that are topologically protected.

On cosmological scales, dark matter so dominates the gravitational behavior of the Universe that, to first approximation, researchers can ignore the gravitational pull of visible matter when simulating the large-scale distribution of galaxies. Still, determining subtle yet important properties of the Universe, such as variations in the amount of dark energy, requires knowing the exact locations of the subatomic particles (baryons) that make up the Universe’s visible matter, as well as what these particles are doing and how they are interacting with dark matter. Now Tassia Ferreira of the University of Oxford, UK, and her collaborators have identified a statistical correlation between two observable features of the Universe that has the potential to reveal the extent of astronomers’ understanding of how baryons shape the large-scale structure of the cosmos [1].

The uncovered correlation is between variations across the sky of the amount of “cosmic shear” and the intensity of the diffuse background of cosmic x rays. Cosmic shear is the apparent warping of the shapes and positions of distant galaxies by the gravitational pulls of intervening clusters of galaxies and other large concentrations of matter. The x-ray background emanates mostly from hot, thin plasma held in the gravitational potentials of those same intervening structures.

Ferreira and her collaborators found that the cosmic shear and the x-ray background are strongly correlated. This correlation is unsurprising given that both features are manifestations of the same dark-matter structures. But the researchers also found that the baryons’ locations influenced how well various physical models reproduced the correlation. One important factor is the amount of plasma (which is made of baryons) that supermassive black holes expel into intergalactic space.

Full episode with Joscha Bach Λ Ben Goertzel is here: https://youtu.be/xw7omaQ8SgANOTE: The perspectives expressed by guests don’t necessarily mirror my own…

This could be the road to quantum computation.

“In contrast, solid-state emitters embedded in a photonic circuit are hardly ‘the same’ due to slightly different surroundings influencing each emitter. It is much harder for many solid-state emitters to build up phase coherence and collectively interact with photons like cold atoms. We could use cold atoms trapped on the circuit to study new collective effects,” Hung continues.

The platform demonstrated in this research could provide a photonic link for future distributed quantum computing based on neutral atoms. It could also serve as a new experimental platform for studying collective light-matter interactions and for synthesizing quantum degenerate trapped gases or ultracold molecules.

Continue reading “Researchers trap atoms, force them to serve as photonic transistors” »

Various large-scale astrophysical research projects are set to take place over the next decade, several of which are so-called cosmic microwave background (CMB) experiments. These are large-scale scientific efforts aimed at detecting and studying CMB radiation, which is essentially thermal radiation originating from the early universe.