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However, “the idea that Saturn’s rings are young seemed very strange in the context of the solar system’s long evolutionary history,” study lead author Ryuki Hyodo, a planetary scientist at the Institute of Science Tokyo, told Space.com. “A few million years ago is the time of the dinosaurs on Earth. This would mean that the solar system was already well-established and relatively stable.”

In contrast, when Saturn formed about 4.5 billion years ago, or during the era called the Late Heavy Bombardment about 4 billion years ago, “the solar system was far more chaotic,” Hyodo said. “Many large planetary bodies were still migrating and interacting, greatly increasing the chances of a significant event that could have led to the formation of Saturn’s rings.”

To shed light on the age of Saturn’s rings, in the new study, Hyodo and his colleagues developed 3D computer models simulating crashes between micrometeoroids and the rings. These impacts typically occur at speeds of about 67,100 mph (108,000 km/h), they said.

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Blog post with audio player, show notes, and transcript: https://www.preposterousuniverse.com/podcast/2023/06/19/240-…-universe/

It’s somewhat amazing that cosmology, the study of the universe as a whole, can make any progress at all. But it has, especially so in recent decades. Partly that’s because nature has been kind to us in some ways: the universe is quite a simple place on large scales and at early times. Another reason is a leap forward in the data we have collected, and in the growing use of a powerful tool: computer simulations. I talk with cosmologist Andrew Pontzen on what we know about the universe, and how simulations have helped us figure it out. We also touch on hot topics in cosmology (early galaxies discovered by JWST) as well as philosophical issues (are simulations data or theory?).

Andrew Pontzen received his Ph.D. in astronomy from the University of Cambridge. He is currently Professor of Cosmology at University College London. In addition to his research in cosmology, he frequently writes popular articles and appears in science documentaries. His new book is The Universe in a Box: Simulations and the Quest to Code the Cosmos.

Mindscape Podcast playlist: https://www.youtube.com/playlist?list=PLrxfgDEc2NxY_fRExpDXr87tzRbPCaA5x.

Dwarf galaxies like the SMC are often un-evolved when it comes to their chemistry because their history of star formation isn’t very extensive, so they haven’t had a chance to build up many heavy elements, such as carbon, nitrogen, oxygen, silicon or iron. NGC 346, for instance, contains about 10% the abundance of heavy elements that star-forming regions in our Milky Way galaxy have. This makes clusters such as NGC 346 great proxies for studying conditions akin to those found in the early universe.

NGC 346 is still forming lots of stars, and JWST found that many of the young ones, with ages of 20 to 30 million years, still possess planet-forming disks around them. Their existence confounds expectations.

“With Webb, we have a strong confirmation of what we saw with Hubble, and we must rethink how we create computer models for planet formation and early evolution in the young universe,” said Guido De Marchi of the European Space Research and Technology Centre (ESTEC) in the Netherlands, who led the research.

Researchers at Rice University have made a meaningful advance in the simulation of molecular electron transfer—a fundamental process underpinning countless physical, chemical and biological processes. The study, published in Science Advances, details the use of a trapped-ion quantum simulator to model electron transfer dynamics with unprecedented tunability, unlocking new opportunities for scientific exploration in fields ranging from molecular electronics to photosynthesis.

Electron transfer, critical to processes such as cellular respiration and energy harvesting in plants, has long posed challenges to scientists due to the complex quantum interactions involved. Current computational techniques often fall short of capturing the full scope of these processes. The multidisciplinary team at Rice, including physicists, chemists and biologists, addressed these challenges by creating a programmable quantum system capable of independently controlling the key factors in : donor-acceptor energy gaps, electronic and vibronic couplings and environmental dissipation.

Using an ion crystal trapped in a vacuum system and manipulated by , the researchers demonstrated the ability to simulate real-time spin dynamics and measure transfer rates across a range of conditions. The findings not only validate key theories of quantum mechanics but also pave the way for novel insights into light-harvesting systems and molecular devices.

Reliably measuring the polarization state of light is crucial for various technological applications, ranging from optical communication to biomedical imaging. Yet conventional polarimeters are made of bulky components, which makes them difficult to reduce in size and limits their widespread adoption.

Researchers at the Shanghai Institute of Technical Physics (SITP) of the Chinese Academy of Sciences and other institutes recently developed an on-chip full-Stokes polarimeter that could be easier to deploy on a large scale. Their device, presented in a paper in Nature Electronics, is based on optoelectronic eigenvectors, mathematical equations that represent the linear relationship between the incident Stokes vector and a detector’s photocurrent.

“This work was driven by the growing demand for compact, high-performance polarization analysis devices in optoelectronics,” Jing Zhou, corresponding author of the paper, told Phys.org. “Traditional polarimeters, which rely on discrete bulky optical components, present significant challenges to miniaturization and limit their broader applicability. Our main goal is to develop an on-chip solution capable of direct electrical readout to reconstruct full-Stokes polarization states.”

Northwestern University engineers are the first to successfully demonstrate quantum teleportation over a fiberoptic cable already carrying internet traffic.

The discovery introduces the new possibility of combining quantum communication with existing internet cables—greatly simplifying the infrastructure required for distributed quantum sensing or computing applications.

The study is published on the arXiv preprint server and is due to appear in the journal Optica.

Quantum walks are a powerful theoretical model using quantum effects such as superposition, interference and entanglement to achieve computing power beyond classical methods.

A research team at the National Innovation Institute of Defense Technology from the Academy of Military Sciences (China) recently published a review article that thoroughly summarizes the theories and characteristics, physical implementations, applications and challenges of quantum walks and quantum walk computing. The review was published Nov. 13 in Intelligent Computing in an article titled “Quantum Walk Computing: Theory, Implementation, and Application.”

As quantum mechanical equivalents of classical random walks, quantum walks use quantum phenomena to design advanced algorithms for applications such as database search, network analysis and navigation, and . Different types of quantum walks include discrete-time quantum walks, continuous-time quantum walks, discontinuous quantum walks, and nonunitary quantum walks. Each model presents unique features and computational advantages.

UC Santa Barbara researchers developed a compact, low-cost laser that matches the performance of lab-scale systems. Using rubidium atoms and advanced chip integration, it enables applications like quantum computing, timekeeping, and environmental sensing, including satellite-based gravitational mapping.

For experiments requiring ultra-precise atomic measurements and control—such as two-photon atomic clocks, cold-atom interferometer sensors, and quantum gates—lasers are indispensable. The key to their effectiveness lies in their spectral purity, meaning they emit light at a single color or frequency. Today, achieving the ultra-low-noise, stable light necessary for these applications relies on bulky and expensive tabletop laser systems designed to generate and manage photons within a narrow spectral range.

But what if these atomic applications could break free from the confines of labs and benchtops? This is the vision driving research in UC Santa Barbara engineering professor Daniel Blumenthal’s lab, where his team is working to replicate the performance of these high-precision lasers in lightweight, handheld devices.

Scientists have found evidence of a strange state of matter called a quantum spin liquid in a material known as pyrochlore cerium stannate.

In this mysterious state, magnetic particles don’t settle into a fixed pattern but stay in constant motion, even at extremely low temperatures. Researchers used advanced tools like neutron scattering and theoretical models to detect unusual magnetic behavior that behaves like waves of light. This breakthrough could lead to new discoveries in physics and future technologies like quantum computing.

Quantum Spin Liquids

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“High-Speed Sequential DNA Computing Using a Solid-State DNA Origami Register” ACS Central Science

DNA stores the instructions for life and, along with enzymes and other molecules, computes everything from hair color to risk of developing diseases. Harnessing that prowess and immense storage capacity could lead to DNA-based computers that are faster and smaller than today’s silicon-based versions. As a step toward that goal, researchers report in ACS Central Science a fast, sequential DNA computing method that is also rewritable — just like current computers.