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Recent middle-distance world records have benefited from a relatively new starting configuration that places some athletes in front groups on outside lanes, reducing the distance they run on tight curves. Using video analysis and physics modeling, researchers found this advantage ranges from 0.1 to over 1 second depending on the event—enough to be the difference between breaking a world record and running a great but unremarkable race.

Two quantum communication channels that are individually worthless for private messaging can actually transmit secret information when used together—a phenomenon physicists thought was impossible. By combining a four-level quantum channel with a qubit erasure channel, researchers achieved over 0.0001903 private bits per use, proving that a channel's individual capacity doesn't fully predict its value for secure communication.

Researchers tried using quantum circuits to improve a classical AI model that predicts power-grid events, but discovered that simply adding more qubits didn't help—the bottleneck was how fast information could enter the quantum system. They developed a new design called "wings" that act as auxiliary circuits, allowing information to flow in through a faster pathway. With this fix, a 12-qubit core system improved from 83.6% to 85.2% accuracy when two wing modules were added, with each wing delivering measurable gains.

Researchers showed that certain mathematical properties of a system's connection graph determine how efficiently you can describe that system using simplified quantum representations. They identified three key graph measures—cutwidth, tree-cutwidth, and a new parameter called learning complexity—that control both the overhead needed for these simplified descriptions and how many measurements you need to learn the system from scratch.

Scientists built QArray+, a physics simulator that runs on graphics processors and can model how quantum dot arrays behave in real time—not just at equilibrium. The simulator is 1,000× faster than earlier tools and captures the non-equilibrium dynamics that matter when measuring quantum states quickly, making it practical to generate the training data needed to automate device tuning.

Physicists have developed a method to run quantum computers that simulate how particles behave in extreme collisions, including cases where particles remember their history—something previous simulations couldn't capture. The approach works by adding a special helper system that tracks this memory and then removing it to recover the full behavior, and it cleanly transitions to simpler models when memory effects become negligible.

Physicists have figured out when a common computational shortcut for quantum systems becomes unreliable. The shortcut—called Krylov truncation—works by approximating quantum behavior using a smaller, manageable system, but information leaks and errors grow over time. The research shows that the method breaks down after a time directly proportional to how the quantum information spreads across the system, with accuracy degrading like a round trip where information must travel out to the edge of the approximation and back.

Researchers developed a quantum algorithm that can map out the full range of energy levels in complex particle theories, revealing everything from their ground state behavior to how they heat up. They tested it on a specific gauge theory using circuits small enough to run on today's superconducting quantum computers, and showed the method uses about half the qubits normally needed while naturally resisting quantum measurement errors.

The shape and size of an ion trap's metal walls directly control the electric-field noise that disturbs trapped ions—and closing the trap makes normal vibrations noisier while tangential ones quieter. Using geometry and billiard-ball mathematics, researchers predicted exactly how different trap configurations alter noise across all ion positions simultaneously, with implications for quantum computing gates that depend on stable ions.

When quantum computers use a computational shortcut called annealing to solve problems, they can get trapped in a dead-end state if the problem crosses a certain type of phase transition. Researchers developed a mathematical framework predicting how many errors pile up during this trap, finding that the error rate follows predictable power-law patterns that shift sharply depending on the problem parameters.

How data centers operate flexibly—by moving computing tasks around or cutting power when needed—can delay expensive power grid expansion, but which strategy works best depends entirely on where the data center sits. In a fossil-fuel-heavy grid like PJM's, shifting work between regions cuts costs by 6–19%; in a carbon-capped grid like Korea's, timing workloads for solar hours works better and avoids building costly batteries.

Physicists created a bizarre state of matter—a Bose-Einstein condensate of dipolar molecules—and discovered they could stretch it into an ellipse using carefully tuned microwave fields. By twisting the orientation of these fields, they could make the entire condensate rotate, offering a new way to study exotic quantum behaviors like vortices and superfluidity in systems dominated by long-range interactions.

Chaotic quantum systems have a hidden structure at their energy edges that makes them surprisingly resistant to disturbance. Researchers found that states at the spectral edge are about one-third as sensitive to small changes as states in the middle of the spectrum, following a universal mathematical pattern that depends on whether the system has time-reversal symmetry.

Quantum computers need to generate random quantum operations for testing and calibration, but a new proof shows that shallow circuits—the speediest option—fundamentally cannot do this job for several important classes of operations. Even when you allow extra helper qubits and operations beyond the target group, the mathematical obstacle remains: you need circuit depth that grows with system size, not shrinks.

Researchers created a quantum encryption system that detects eavesdropping in a radically different way: by putting the sender and receiver's operations into quantum superposition so their order becomes undefined. Unlike standard quantum encryption methods that require publicly revealing and discarding part of the raw key to spot tampering, this approach kept every bit potentially usable for the final key while still catching eavesdroppers 15% of the time per qubit.

When a quantum system coupled tightly to its environment is suddenly disturbed, the amount of work it absorbs follows an unexpected pattern: near the minimum energy cost, the probability drops off according to a mathematical power law rather than smoothly. Researchers developed a precise computational method that captures this behavior exactly, even in the notoriously difficult regime where the system and environment are so strongly entangled that standard approximations fail.

Physicists tested whether fundamental speed-accuracy tradeoffs hold up in quantum systems when interactions are added. The bounds remained valid in some cases but broke down in others depending on how the system's interactions were defined—suggesting that nonlinearities pose a real threat to these limits that theorists had thought were rock-solid.

Physicists discovered that quantum materials possess a special geometric structure that determines how they bend light and generate electric current — even in messy, real-world conditions with disorder and interactions. By developing a new mathematical framework called the cQAC tensor, the researchers derived exact rules connecting this geometry to measurable electrical responses, and showed that geometric effects can dominate the total response in multiband insulators.

A mathematical model shows how a single external actor can influence a synchronized network by pulling it toward a different frequency. The researchers found critical tipping points: push too hard and the network fragments; adjust the pressure carefully and the group syncs up at a new frequency set by the influencer rather than their natural rhythm.

Physicists discovered that quantum systems interacting strongly with heat baths often fail to reach thermal equilibrium—even when the coupling is weak, which defies everyday thermodynamic intuition. The researchers identified specific conditions and parameter choices that restore equilibrium behavior, and showed how to combine different types of mathematical models to maintain consistent temperatures across the system.

Quantum systems usually need defects or particle interactions to behave chaotically, but this work shows that geometry alone can do it. When quantum particles hop across randomly-wired networks, the shape and connectivity of those networks dictates whether chaos emerges—independent of any material disorder. Large networks generated robust chaos and smooth energy spreading, while thin, highly interconnected ones created a split personality: some particles localized in place while others moved freely.

Physicists have developed a systematic method to create larger and more efficient quantum error-correcting codes by mathematically "lifting" existing ones while keeping their core structure intact. The approach yields codes with better performance than previously available versions and makes it cheaper in terms of physical resources to perform reliable quantum operations on these codes.

A study of seven major Bitcoin liquidation crashes found no single early-warning signal that works across all events. Price showed telltale signs of instability before five crashes but completely failed to warn of two sudden news-driven collapses; only a compression in trading order-flow emerged as a consistent (though imperfect) precursor across all events. This suggests crypto crashes fall into at least two different types—those that build up gradually and those triggered suddenly by external shocks—each with its own fingerprint.

Physicists have found a way to verify that pairs of photons are quantum-entangled without waiting around for the notoriously difficult task of catching both photons at the detector simultaneously. By flooding one part of the photon pair with bright classical light and measuring what comes out, they can now certify entanglement using ordinary intensity measurements—the same kind a simple camera makes. The team demonstrated this works across the full spatial properties of the photon pairs.

Researchers have designed the first complete blueprint for using fault-tolerant quantum computers to simulate atomic nuclei — a problem that's been largely overlooked despite its similarities to chemistry simulations. The resource requirements for simulating certain nuclei (like magnesium-32) are comparable to current chemistry benchmarks, though simulating lighter nuclei would require substantially more computing power.

Physicists discovered that tweaking how strongly light couples to atoms can trigger a sudden, sharp change in how chaotically a quantum system evolves—visible through a mathematical measure called Krylov complexity. The transition marks the boundary between two fundamentally different types of quantum behavior, where the system switches from being orderly and confined to becoming wild and spreading.

A mathematical model shows that political corruption can become a stable, self-sustaining system rather than merely the sum of individual bad actors. Once corruption reaches a critical threshold in how officials interact and support each other, the system locks in place — small anti-corruption efforts fail to budge it, and corruption persists across elections and crises.

Physicists discovered that quantum particles hopping on a branching network with randomly weak connections can enter an unusual state that is neither fully spread out nor fully trapped. The particles occupy most of the network, yet concentrate their energy in a way normally seen only in completely localized systems—a phenomenon the researchers call semi-fractality. By varying the strength of the weak links, they found the system can shift between this semi-fractal regime and complete localization, revealing a new intermediate form of quantum confinement.

Physicists have developed a faster way to simulate quantum systems by replacing expensive mathematical operations with cheaper ones that run well on modern computers. The new method is up to 100 times faster than the previous standard approach, completing calculations on a single graphics processor that would have taken vastly longer before.

Researchers discovered that microscopic metallic grains embedded in quantum computer materials are a major source of signal degradation, matching the impact of the previously identified culprit known as two-level system defects. These grains are created during standard manufacturing and had been overlooked because existing diagnostic tools misidentified their damage as coming from other sources.

When charged particles emit photons, they don't have a single well-defined energy boundary—instead they fade out gradually at the edge, following a mathematical power law. Rey shows this fuzzy edge comes directly from soft photons we can't measure individually, and that the exact shape of this edge encodes information about how those unmeasured photons behave.

Physicists discovered that certain quantum detectors fail catastrophically when they cross the edge of a black hole, producing mathematical infinities that can't be resolved. The breakdown happens specifically when detectors measure nonlinear properties like momentum or energy density, suggesting the popular "firewall" model of black hole boundaries may be fundamentally incompatible with how these detectors work.

Researchers designed a quantum heat engine using superconducting circuits that can approach the theoretical efficiency limit (Carnot efficiency) while still producing useful power—something impossible for classical engines. The trick is harnessing collective quantum effects that boost the engine's activity in ways classical systems cannot match.

When multiple identical four-level atoms are arranged in certain geometric configurations, they emit light in coordinated bursts that grow much faster than expected—following a mathematical power law where the peak brightness scales roughly with the square of the number of atoms rather than linearly. Researchers developed a unified mathematical framework using group theory to predict and explain these synchronized emission patterns across seven different atomic geometries.

A physicist has figured out how to calculate the partition function—a fundamental quantity describing quantum behavior—for wormholes in string theory by working from charge-sector data. The method reconstructs what happens when quantum fields traverse these hypothetical shortcuts through spacetime, revealing mathematical constraints and symmetries these wormhole properties must obey.

Physicists have found a new way to tell whether a quantum system behaves in an orderly, predictable way or descends into chaos — and it works even when the system is exposed to environmental noise. The approach, based on measuring quantum correlations between particles, outperforms the standard method in certain noisy conditions, especially when the noise has a memory effect that lets quantum information leak back into the system.

Physicists mapped out exactly how quantum systems transition from behaving in predictable, orderly ways to becoming completely chaotic—a shift that happens when you gradually introduce rule-breaking into an otherwise perfectly symmetric system. By studying a model circuit and tracking how information scrambles over time, the team identified the precise mechanisms, speeds, and distances involved in this tipping point.

Researchers proved that a specific type of quantum error-correction code, when combined with a spatial coupling technique and a particular decoding algorithm, can reach the theoretical performance limit for correcting erasure errors. The breakthrough shows that this practical decoding method works as well as the best theoretically possible method, closing a gap between theory and what's actually implementable.

Physicists have developed a streamlined method for simulating how quantum systems evolve when they're knocked out of equilibrium—a notoriously hard problem because the complexity explodes exponentially. Instead of tracking all the mathematical details, the new approach focuses only on operators that act on small, localized regions of the system, discarding the rest as negligible. Tests on two benchmark quantum systems show this simplified method accurately predicts correlation patterns and how energy and particles move through the system, while cutting computational demand significantly.

Physicists have figured out how to exactly predict how parts of certain quantum systems evolve over time, even when those parts are constantly jostled by the rest of the system around them. They showed that a specific type of quantum rule called Rule 201 can be solved mathematically using a compact mathematical structure, making it possible to calculate how quantum properties change moment by moment without the usual explosion of complexity.

Researchers used an AI language model paired with mathematical rules to discover new quantum error-correcting codes that could help scale up quantum computers. The AI system found dozens of competitive code designs by evolving mathematical specifications, including some based on non-abelian groups that were never explored before in this context.

Researchers designed communication tasks that can definitively prove when two quantum devices are genuinely incompatible — meaning they cannot both operate simultaneously in the same quantum system. The proof works without needing to know the internal details of the devices, and reveals a new way quantum systems outperform classical ones in communication tasks.

Researchers expanded how to build topological codes—a leading approach to protecting quantum computers from errors—by relaxing the requirement that they repeat perfectly across space. The new codes combine translation symmetry with rotations and reflections, and surprisingly, they can require fewer qubits in practice than the standard designs, making them simpler to build.

Quantum networks face a fundamental trade-off: the longer you run a quantum link without maintenance, the more its signal quality degrades, but pausing to recalibrate takes the link offline entirely. Researchers developed a mathematical protocol that automatically decides how long each link should operate before recalibrating, balancing quality against availability to meet a network's performance needs.

Physicists have identified how to harness the quantum environment surrounding tiny conductors to reduce noise and boost measurement precision. The key is tuning the bandwidth of this environment to create synchronized interference patterns in electron flow, allowing devices to achieve better precision than systems without this engineered memory effect.

Researchers proved that for a broad class of optimization problems, even quantum computers face fundamental speed limits when trying to beat classical algorithms. On problems where each variable connects to at most D constraints, any quantum advantage shrinks to just a constant improvement — the hard part (improving by roughly 1/√D) remains equally hard for both quantum and classical machines.

Physicists created a special quantum state in ultracold atoms that mimics a theoretical arrangement predicted to host particles with unusual braiding properties—a key building block for quantum computers. Using precise measurements, they confirmed the state had the expected pairing structure, marking the first direct observation of this arrangement in a controlled laboratory setting.

Physicists developed a mathematical toolkit for understanding how quantum fields behave in warped spacetimes—curved geometries that include cosmic defects like strings and monopoles. By breaking down the complex geometry into simpler pieces, they derived exact solutions showing how fields vibrate around these defects, with specific predictions for how particles pop in and out of existence near a monopole in anti-de Sitter space.

Physicists have shown that quantum systems described by a particular mathematical framework cannot evolve the same way backward as forward in time—a fundamental asymmetry encoded in the ratio 2/3. When they modeled the behavior of ultracold lithium atoms using this framework, they found that collapse effects grew a trillion times stronger in the forward direction than the reverse, matching none of the symmetric collapse models currently used in physics.

In a simplified model of interacting electrons with unusual physical properties, researchers found that breaking symmetry rules (a non-Hermitian feature) dramatically amplifies the tendency for electrons to bunch up in ordered patterns. This effect is strongest at special points in the system where the usual rules of quantum mechanics start to fail, and a reliable diagnostic tool called the topological marker successfully tracks when and where this bunching occurs.

The International Astronomical Union has built a framework called the Flagship Ecosystem that helps countries use astronomy education and research to address poverty, inequality, and lack of skilled workers. The system combines funding, training, open resources, and communities of practice to make astronomy-based development projects easier to launch and scale across different regions.

Physicists discovered that by rapidly switching electric fields around two tiny barriers in a quantum channel, they can trap particles temporarily and control whether they pass through or bounce back. The spacing between the barriers and the strength of the oscillations determine whether particles get stuck in "bound states"—special configurations where they linger far longer than physics normally allows.

When laser beams carrying data travel through a turbulent atmosphere, turbulence scrambles their structure and spreads their power across multiple beam patterns. Researchers created a mathematical model that predicts exactly how much power leaks from the original beam pattern into neighboring ones—and found the loss scales predictably with distance, following a simple formula that works even over very long paths.

Researchers found that constantly measuring a chain of quantum particles fundamentally changes how quickly disorder spreads through the system. At low measurement rates, a boundary between up and down spins expands rapidly; at high rates, it moves sluggishly—a shift called the ballistic-to-diffusive transition. This transition is directly linked to how entanglement (quantum correlation) builds up in the system and can be observed in real experiments without complex filtering tricks.

When people hold multiple related beliefs rather than a single opinion, the way those beliefs connect internally changes how groups reach consensus. Researchers modeled this by giving each person a personal network of three beliefs (for or against, or neutral) linked in different patterns, then watched how groups with these varied belief structures influenced each other. They found that certain internal belief structures make groups more resistant to polarization, but only up to a point—adding more beliefs helps less and less.

Researchers discovered that a key measurement of quantum instability in driven systems has a hidden geometric meaning: it describes how fast a quantum state moves through a particular mathematical landscape. More importantly, they found that nonlinear effects naturally put the brakes on this runaway behavior, creating a built-in limit to how chaotic the system becomes.

Researchers demonstrated a new way to control how quickly quantum information decays in qubits by engineering surfaces that manipulate low-frequency magnetic noise around them. Unlike previous approaches that focused on spontaneous emission, this method targets pure dephasing—the gradual loss of quantum coherence—using specially designed cobalt-iron-boron metasurfaces placed near nitrogen-vacancy centers in diamond. The technique opens a new path for protecting quantum information without relying on optical engineering.

When quantum computers try to solve logic puzzles using Grover's algorithm, the way you write down the puzzle matters enormously for how many quantum resources you need. Researchers found that switching from the standard way of writing these puzzles (CNF) to a different format called ESOP cuts the number of quantum bits needed, reduces complex quantum gates, and shrinks the overall circuit — sometimes substantially — while solving the same problems.

Researchers discovered a new way to create long-range quantum entanglement in mixed states—a halfway point between pure and completely random quantum systems. The key insight: when you restrict a quantum system to stay symmetric under translations, the simple, short-range entangled states that normally fill the space are vastly outnumbered by complex, long-range entangled ones. This happens not because of exotic quantum phenomena, but simply because there's more room for complexity.

Researchers developed a new approach that allows recurrent neural networks to efficiently simulate quantum systems at scale, reaching lattices as large as 52×52 sites while matching results from established quantum simulations. By harnessing recent advances in parallel processing, they overcame the common assumption that recurrent networks are too sequential for quantum problems and showed these models can work reliably on modest computers.

Researchers showed how to create special quantum defects by slightly disturbing a topologically ordered quantum system — defects that could enable a new form of quantum computing through defect braiding. The team mapped out the energy spectrum of these synthetic defects and pinpointed the quantum phase transition that triggers their emergence, filling a gap in a decade-old theoretical proposal that had never been systematically tested.

A new method for zooming in and out on networks where two different types of things interact—like plants and pollinators, or actors and movies—reveals multiscale structure that standard techniques miss. When researchers compressed these bipartite networks the usual way, they erased crucial information about role separation; the new approach preserves it, uncovering hidden hierarchies that traditional analysis overlooks.

Physicists have designed a way to control magnetic behavior in one material by attaching a quantum magnetic layer next to it. The quantum layer acts like a bath that damps and drives the classical magnetic material, creating new ways to tune how magnetic waves, domain walls, and skyrmions (tiny magnetic vortices) move and disappear. This could let engineers manipulate magnetic dynamics without direct electrical or magnetic contact.

Researchers built a device that converts signals between microwave circuits in quantum computers and optical fibers with less thermal noise than previous designs. By combining two materials—silicon and lithium niobate—using a precise printing technique, they achieved the strong signal conversion needed for practical quantum-to-optical communication.

A quantum state satisfies a "strong Markov property" if you can recover lost information about it by measuring just one copy and applying a local fix — and this works the same way regardless of what you actually measure. The researchers show this property is equivalent to a simpler mathematical condition: correlations must decay in a particular way, and they prove three surprising consequences, including that you can estimate multiple properties of a quantum state from a single measurement.

Researchers demonstrated that quantum computers can simulate how fluids move and mix under varying flow patterns — a step toward realistic fluid dynamics calculations on quantum hardware. Using IonQ's trapped-ion systems, they solved the advection-diffusion equation in three dimensions and identified a major bottleneck: repeatedly reading out and reloading fluid density data. They propose using a technique called MPS shadow tomography to make this process faster at scale.