Science – Page 151

Decoding Quantum Chaos with Correlator Signals

02.12.2025 by pricpr

New research reveals how higher-order quantum correlations can unlock a detailed understanding of complex many-body dynamics.

Beyond Chance: Refining Quantum Randomness Certification

01.12.2025 by pricpr

$The distribution of Bell certificates, quantified by Shannon entropy, reveals a classification based on the randomness they yield, with analysis demonstrating that even with a white noise value of $1\mathrm{e}{-6}$, distinctions arise between Shannon and min-entropy measurements of certificate quality.$

A new study systematically evaluates Bell inequality-based protocols to bolster the security and reliability of quantum random number generators.

Beyond Classical Limits: Quantum CSPs and the Power of Commutativity

01.12.2025 by pricpr

New research explores how leveraging quantum properties can redefine the boundaries of solvable constraint satisfaction problems.

Untangling the Quantum Realm: How Topology Shapes Entanglement

01.12.2025 by pricpr

$The study demonstrates that, for two circle states exhibiting $ \Delta = 0 $ and coinciding within the Metaplectic group, an antipodal entanglement condition-regulated by a control parameter $ \rho = \pi $-does not fundamentally alter the entanglement’s classicalization, indicating a robustness in the system's behavior despite variations in entanglement phase.$

New research reveals a surprising link between the geometric properties of space and the delicate phenomenon of quantum entanglement, offering insights into the transition from quantum to classical behavior.

Cycles, Entanglement, and Quantum Advantage

01.12.2025 by pricpr

New research reveals how topological properties of game cycles connect to the power of quantum strategies, offering insights into the fundamental limits of computation.

Squeezing Information from the Edge of Chaos

01.12.2025 by pricpr

$The study demonstrates that the long-time growth rate $k_F$ of the Fisher information $F(\varphi, s)$ under homodyne detection is optimized not at backaction-evading conditions ($\varphi = 0.6$), but rather at general-dyne measurements identified by parameters $(s_{opt}, \varphi_{opt}) = (0, 0.583)$, achieving a maximized Fisher information that surpasses the global quantum Fisher information $I_{G}$.$

New research reveals how harnessing quantum measurement backaction at critical points can dramatically improve the precision of continuous sensing protocols.

Beyond the Limit: Quantum Sensing with Geometric Phase

01.12.2025 by pricpr

Longitudinally-coupled qubit-oscillator systems undergo free evolution within oscillator phase space, and a geometric protocol-involving a specific sequence of operations-manipulates this motion, demonstrating how control sequences dictate the system’s trajectory and revealing the fundamental interplay between quantum states and classical dynamics.

A new approach leverages the geometric phase in qubit-oscillator systems to achieve enhanced sensitivity in quantum sensing applications.

Beyond the Quantum Limit: Harnessing Non-Commutation for Precision Measurement

01.12.2025 by pricpr

$Quantum estimation schemes explore varied approaches to parameter inference, ranging from sequential applications of a parameter-encoding operator $H^\lambda$ to more complex, coherently controlled, non-commutative sequences involving both $H^g$ and $H^\lambda$ repeated $N$ times, ultimately demonstrating a progression in encoding strategies for enhanced precision.$

A new framework reveals how the fundamental non-commutative nature of quantum mechanics can be exploited to dramatically enhance the precision of measurements, surpassing established limits.

Time Crystals Illuminate the Path to Ultra-Precise Sensing

01.12.2025 by pricpr

$A boundary time crystal functions as a tunable light source and decoder, encoding phase information onto emitted photons via a unitary transformation $e^{-i\hat{\Lambda}\varphi}$ and revealing it through monitoring time-averaged intensity, where a zero phase difference renders the decoder a perfect absorber, and homodyne detection sensitive to the phase difference between the input field and a local oscillator.$

Researchers have harnessed the unique properties of boundary time crystals to create a light source capable of surpassing the standard limits of measurement precision.

Recommender Systems That Adapt to Change

30.11.2025 by pricpr

The system models data generation as a temporal process shaped by both fluctuating factors $𝐯$ and stable characteristics $𝐬$, acknowledging that observed samples $𝐱$ and their labels $𝐲$ are ultimately products of latent representations $𝐳$ and inherent causal dependencies-a framework anticipating inevitable shifts in distribution over time.

New research tackles the challenge of maintaining accuracy as user preferences and data patterns evolve over time.