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This ultracold quantum device turns electricity into something far stranger that could unlock sound-based lasers

Researchers at McGill University have developed a novel device that generates sound-like particles known as phonons at extremely cold temperatures. The technology could be used to create phonon lasers, with possible applications in communications and medical diagnostics.

“Modern communication is largely based on light, including electromagnetic waves and electrical currents. In a medium such as oceans, sound can travel, whereas light and electrical currents cannot,” said Michael Hilke. “In the human body, sound waves can also be a useful tool.”

Hilke is Associate Professor of Physics and co-author of the study published in Physical Review Letters. The device was built and analyzed at McGill and the National Research Council of Canada. The material was synthesized at Princeton University.

Single X-ray photons reveal hidden light-matter interactions in 50-nanometer double slits

A rainbow reveals with colors what otherwise remains hidden: light is “refracted” by transparent matter, in this case water droplets. This same physical effect underlies many everyday technologies, like LCD screens and broadband connections based on fiber-optic cables. Light refraction is caused by an interaction between light and the atoms of matter. This brings the light waves slightly out of sync, so to speak. “X-ray light” is “refracted,” too. But the effect is difficult to measure here.

A miniature device now offers a novel approach: Researchers from the Universities of Göttingen and Hamburg, together with partners, have built the world’s smallest X-ray interferometer, to their knowledge. It has enabled them to precisely measure, for the first time, the refraction of X-rays confined to a few nanometers, and to deduce how they interact with atomic nuclei. The study was published in the journal Nature Photonics.

The new X-ray interferometer is based on the famous double-slit experiment, which Nobel laureate Richard Feynman said “has in it the heart of quantum mechanics.”

Fragile no more, nickelates get an upgrade that changes how superconductivity endures

Discovered in 2019, the material known as nickelates has intrigued researchers for its potential to become a superconductor at elevated temperatures—a property that could significantly advance such fields as quantum science and energy transmission. However, it’s a very unstable material and difficult to work with. But the lab of Professor Charles Ahn has developed a method that could enhance superconductivity in these materials. The results are published in Nature Communications.

With their ability to conduct electricity with no resistance, superconductors are a key component to quantum computing, medical imaging, and a number of other fields. A group of copper-oxide compounds known as cuprates have long been central to the study of high-temperature superconductivity (“high temperature” is a relative term—they still need to be kept in very cold environments). Nickelates are especially exciting because they share some of cuprates’ key electronic features while offering a new platform for materials design and tuning.

Enter nickelates, a material with many similarities to cuprates, but with the potential to eventually become even more useful to scientists. Dung Vu, a postdoctoral associate who led the study, noted that synthesizing nickelate thin films is “notoriously difficult.” The Ahn lab is one of the few in the world with the ability to do so.

A physicist reveals how time travel is possible | Jim Al-Khalili

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Time is the one thing every human being experiences identically, or so we assume.

Physicist Jim Al-Khalili dismantles that assumption, explaining how velocity and gravity don’t just affect clocks but actually alter the rate at which time passes for the person experiencing it.

Preorder Jim Al-Khalili’s forthcoming book, On Time: The Physics That Makes the Universe, here: https://www.amazon.com/Time-Physics-T?tag=lifeboatfound-20

About Jim Al-Khalili: Jim is a multiple award-winning science communicator renowned for his public engagement around the world through writing and broadcasting and a leading academic making fundamental contributions to theoretical physics, particularly in nuclear reaction theory, quantum effects in biology, open quantum systems and the foundations of quantum mechanics. Jim is a theoretical physicist at the University of Surrey where he holds a Distinguished Chair in physics as well as a university chair in the public engagement in science. He received his PhD in nuclear reaction theory in 1989 and has published widely in the field. His current interest is in open quantum systems and the application of quantum mechanics in biology.

About Jim Al-Khalili:

Quantum-informed machine learning for predicting spatiotemporal chaos with practical quantum advantage

Ultimately, QIML proves that we don’t need a fully fault-tolerant quantum computer to see results. By using quantum processors to learn the complex “rules” of chaos, we can give classical computers the boost they need to make reliable, long-term predictions about the most turbulent environments in the natural world.


Modeling high-dimensional dynamical systems remains one of the most persistent challenges in computational science. Partial differential equations (PDEs) provide the mathematical backbone for describing a wide range of nonlinear, spatiotemporal processes across scientific and engineering domains (13). However, high-dimensional systems are notoriously sensitive to initial conditions and the floating-point numbers used to compute them (47), making it highly challenging to extract stable, predictive models from data. Modern machine learning (ML) techniques often struggle in this regime: While they may fit short-term trajectories, they fail to learn the invariant statistical properties that govern long-term system behavior. These challenges are compounded in high-dimensional settings, where data are highly nonlinear and contain complex multiscale spatiotemporal correlations.

ML has seen transformative success in domains such as large language models (8, 9), computer vision (10, 11), and weather forecasting (1215), and it is increasingly being adopted in scientific disciplines under the umbrella of scientific ML (16). In fluid mechanics, in particular, ML has been used to model complex flow phenomena, including wall modeling (17, 18), subgrid-scale turbulence (19, 20), and direct flow field generation (21, 22). Physics-informed neural networks (23, 24) attempt to inject domain knowledge into the learning process, yet even these models struggle with the long-term stability and generalization issues that high-dimensional dynamical systems demand. To address this, generative models such as generative adversarial networks (25) and operator-learning architectures such as DeepONet (26) and Fourier neural operators (FNO) (27) have been proposed. While neural operators offer discretization invariance and strong representational power for PDE-based systems, they still suffer from error accumulation and prediction divergence over long horizons, particularly in turbulent and other chaotic regimes (28, 29). Recent work, such as DySLIM (30), enhances stability by leveraging invariant statistical measures. However, these methods depend on estimating such measures from trajectory samples, which can be computationally intensive and inaccurate in all forms of chaotic systems, especially in high-dimensional cases. These limitations have prompted exploration into alternative computational paradigms. Quantum machine learning (QML) has emerged as a possible candidate due to its ability to represent and manipulate high-dimensional probability distributions in Hilbert space (31). Quantum circuits can exploit entanglement and interference to express rich, nonlocal statistical dependencies using fewer parameters than their promising counterparts, which makes them well suited for capturing invariant measures in high-dimensional dynamical systems, where long-range correlations and multimodal distributions frequently arise (32). QML and quantum-inspired ML have already demonstrated potential in fields such as quantum chemistry (33, 34), combinatorial optimization (35, 36), and generative modeling (37, 38). However, the field is constrained on two fronts: Fully quantum approaches are limited by noisy intermediate-scale quantum (NISQ) hardware noise and scalability (39), while quantum-inspired algorithms, being classical simulations, cannot natively leverage crucial quantum effects such as entanglement to efficiently represent the complex, nonlocal correlations found in such systems. These challenges limit the standalone utility of QML in scientific applications today. Instead, hybrid quantum-classical models provide a promising compromise, where quantum submodules work together with classical learning pipelines to improve expressivity, data efficiency, and physical fidelity. In quantum chemistry, this hybrid paradigm has proven feasible, notably through quantum mechanical/molecular mechanical coupling (40, 41), where classical force fields are augmented with quantum corrections. Within such frameworks, techniques such as quantum-selected configuration interaction (42) have been used to enhance accuracy while keeping the quantum resource requirements tractable. In the broader landscape of quantum computational fluid dynamics, progress has been made toward developing full quantum solvers for nonlinear PDEs. Recent works by Liu et al. (43) and Sanavio et al. (44, 45) have successfully applied Carleman linearization to the lattice Boltzmann equation, offering a promising pathway for simulating fluid flows at moderate Reynolds numbers. These approaches, typically using algorithms such as Harrow-Hassidim-Lloyd (HHL) (46), promise exponential speedups but generally necessitate deep circuits and fault-tolerant hardware.

Quantum-enhanced machine learning (QEML) combines the representational richness of quantum models with the scalability of classical learning. By leveraging uniquely quantum properties such as superposition and entanglement, QEML can explore richer feature spaces and capture complex correlations that are challenging for purely classical models. Recent successes in quantum-enhanced drug discovery (37), where hybrid quantum-classical generative models have produced experimentally validated candidates rivaling state-of-the-art classical methods, demonstrate the practical potential of QEML even before full quantum advantage is achieved. Despite these strengths, practical barriers remain. QEML pipelines require repeated quantum-classical communication during training and rely on costly quantum data-embedding and measurement steps, which slow computation and limit accessibility across research institutions.

Chip Can Project Video the Size of a Grain of Sand

Engineers have created a 1-square-millimeter chip that can project a photograph onto an area smaller than the size of two human egg cells. This precise laser control could have applications in augmented reality, biomedical imaging, and quantum computing.


MEMS array to steer lasers for quantum computer finds other uses.

Surprise: There was a universe before the Big Bang | Ethan Siegel

“Asking the question of, where did the entire universe come from, is no longer a question for poets and theologians and philosophers. This is a question for scientists, and we have some amazing scientific answers to this question that have defied even the wildest of our expectations.” Subscribe to Big Think on YouTube ► / @bigthink Up next, The mind-blowing circle of life, explained by a biologist ► • The mind-blowing circle of life, explained… Ethan Siegel, theoretical astrophysicist and science communicator, author of the James Webb Space Telescope book, “Infinite Cosmos,” and writer of the science blog, “Starts With A Bang” joins us to explore the cosmic origins of our universe. Read Ethan’s companion article: https://bigthink.com/starts-with-a-ba… — Where did the entire universe come from? 0:57 — A question for scientists 1:43 — The quest for the beginning of the universe 2:21 — Hubble’s telescope 4:09 — Extragalactic objects 5:11 — Blueshifted vs redshifted 6:53 — General theory of relativity 7:50 — The cosmic egg 8:26 — The origin of The Big Bang 9:55 — A cosmological constant 14:24 — Scale invariant spectrum 15:13 — Testing for Cosmic Inflation 19:34 — Our cosmic origins 21:03 — Ethan Siegel, kilt influencer Read the video transcript ► https://bigthink.com/series/the-big-t

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About Ethan Siegel: Ethan Siegel is a Ph.D. astrophysicist and author of “Starts with a Bang!” He is a science communicator, who professes physics and astronomy at various colleges. He has won numerous awards for science writing since 2008 for his blog, including the award for best science blog by the Institute of Physics. His three books “Treknology: The Science of Star Trek from Tricorders to Warp Drive,” “Beyond the Galaxy: How humanity looked beyond our Milky Way and discovered the entire Universe,” and “Infinite Cosmos: Visions From the James Webb Space Telescope” are available for purchase at Amazon. Follow him on X @startswithabang.

Quantum Signatures of Proper Time in Optical Ion Clocks

A new theoretical paper shows that trapped-ion optical clocks could directly probe subtle effects at the intersection of quantum mechanics and general relativity — including the superposition of proper times and entanglement induced by time dilation.

By leveraging the extreme precision of these clocks, researchers demonstrated an experimental route to exploring phenomena that go beyond what current atomic clocks can access, even as today’s devices already account for relativistic time dilation.

Read more in Physical Review Letters.


High-precision clocks based on quantum systems will work in a regime where a quantum description of proper time might be necessary.

One-way phonon synchronization could survive noise and defects, theoretical physicists suggest

A novel approach for realizing the one-way quantum synchronization of phonons has been proposed by three theoretical physicists at RIKEN. Importantly, this method is remarkably resilient against practical challenges such as imperfections and environmental noise. Their paper, “Nonreciprocal quantum synchronization,” is published in Nature Communications.

Many devices use components that act as one-way streets, allowing particles to travel in one direction, but almost not at all in the opposite one. These so-called nonreciprocal components are widely used in microwave and light-based systems for things such as controlling signal flow and preventing reflections.

“Nonreciprocal components enable signals to travel along desired paths, whereas they are strongly attenuated in the opposite direction,” notes Franco Nori of the RIKEN Center for Quantum Computing (RQC). “This ability finds applications ranging from signal processing to invisible cloaking.”

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