Quantum Physics
Strong Quantum Mpemba Effect from Exact Slow-Mode Selection in Constrained Rydberg Chains
Mingdi Xu, Kaixiang Lu, Zijun Wei et al. (+3 more)
CStrong
quantum Mpemba acceleration requires suppressing the slowest visible Liouvillian relaxation channel, but a robust many-body mechanism for enforcing such suppression remains challenging. We identify such a mechanism in locally dephased constrained Rydberg chains through exact slow-mode selection. For constrained single-
spin-flip
Hamiltonians, local dephasing turns the
Hamiltonian itself into an exact left Liouvillian eigenmode, $\mathcal L^\dagger(H)=-\gamma H$. A finite-temperature reference state generically overlaps with this $H$-like slow mode, whereas translationally invariant states with $\mathrm{Tr}(H\rho_0)=0$ remove it and are confined to the $Q=0$ operator sector. When the next visible $Q=0$ mode decays faster, these selected states exhibit a strong
quantum Mpemba effect. We demonstrate this mechanism in the PXP chain for a zero-energy scar eigenstate, the all-zero product state, and a translation-invariant $Z_2$ cat state, and show that it persists in the $(2,3)$ model and the longer-range blockade family. Our results identify Liouvillian mode visibility, rather than special scar wave functions, as the organizing principle for anomalously fast relaxation in constrained open
quantum systems.
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All authors Mingdi Xu, Kaixiang Lu, Zijun Wei, Xiang-Ping Jiang, Haiping Hu, Lei Pan
Medical Physics
Review of oxygen measurement and relevance to the mechanisms of FLASH radiotherapy
Brian W. Pogue, David I. Hunter, Corbin Narita et al. (+3 more)
FLASH radiotherapy (FLASH-RT) is the phenomenon of relative sparing of normal tissue when ultra-high dose rates (UHDR) are used compared with conventional dose rates (CDR) as clinically used. Despite extensive investigation, the underlying mechanisms remain unexplained. Among the proposed hypotheses, tissue oxygen has consistently been a central theme because oxygen is the most dominant factor known to modulate radiation-induced damage. The factors implicated in FLASH sparing include the baseline partial pressure of oxygen (pO2), transient radiolytic oxygen consumption (ROC), and oxygen-dependent changes in the chemistry of reactive oxygen species (ROS) that vary with dose rate. This review synthesizes current evidence on in vivo oxygen measurement techniques, highlighting their capabilities and limitations in capturing the spatial and temporal heterogeneity of tissue oxygenation. Key experimental studies in skin are summarized and interpreted by modulating oxygen levels via changes in inspired oxygen gas and vascular clamping interventions, demonstrating that the FLASH effect occurs only at intermediate baseline pO2 (normoxic or slightly hypoxic) values, but not at hypoxia or hyperoxia. Direct measurement of oxygen consumption during UHDR irradiation is possible, providing one of the first in situ measurements of radiation chemistry in patients. In parallel, recent advances in fast in vitro radiation chemistry assays indicate that UHDR irradiation alters radical yields, favoring increased production of solvated electrons and reduced hydroxyl radical mediated damage. Taken together, the available data suggest that the FLASH sparing effect arises from an interplay among the delivered dose and dose rate, local oxygen availability, and radiation chemistry, with tissue-specific variation in scavenging, leading to altered biological responses across the CDR-to-UHDR shift.
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All authors Brian W. Pogue, David I. Hunter, Corbin Narita, William S. Thomas, Xu Cao, Harold M. Swartz
High Energy Astrophysical Phenomena
The Complete Catalog of Gamma-Ray Transients Observed by GRBAlpha & VZLUSAT-2 CubeSat Missions
Marianna Dafcikova, Jakub Ripa, Andras Pal et al. (+45 more)
We present the largest sample of gamma-ray transients observed by any CubeSat mission so far. Observations were acquired by a 1U CubeSat GRBAlpha, the smallest astrophysical space observatory, and a 3U CubeSat VZLUSAT-2. Both missions were technological pathfinders and carried a novel CsI scintillator-based detector read-out by silicon photomultipliers. They operated on Sun-synchronous low Earth orbits below 550 km for about four years; GRBAlpha between March 2021 and June 2025 while VZLUSAT-2 between January 2022 and November 2025. Despite being technological experiments, they observed over 300 gamma-ray transients including gamma-ray bursts (GRBs),
solar flares, soft gamma repeaters and one outburst from an X-ray binary. Among these are the two brightest GRBs ever observed, GRB 221009A and GRB 230307A, without saturation and GRBs at
redshifts up to z=4.2. GRBAlpha also contributed to the InterPlanetary Network. Regular monitoring of transients was demonstrated by a detection rate of two transients or one GRB a week and the shortest time between two subsequent detections of only 42 minutes. We show that a constellation of nanosatellites around the Earth would observe at least 60% of
Fermi/GBM GRBs with 5$\sigma$ significance and over 90% at 3$\sigma$ level. GRBAlpha and VZLUSAT-2 prove that routine monitoring of the gamma-ray sky can also be done by low-cost and quickly developed nanosatellite missions.
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All authors Marianna Dafcikova, Jakub Ripa, Andras Pal, Norbert Werner, Michaela Duriskova, Yasushi Fukazawa, Martin Kolar, Laszlo Meszaros, Filip Munz, Masanori Ohno, Lea Szakszonova, Hiromitsu Takahashi, Masato Yokota, Jean-Paul Breuer, Hsiang-Kuang Chang, Balazs Csak, Vladimir Daniel, Juraj Dudas, Marcel Frajt, Gabor Galgoczi, Peter Hanak, Filip Hroch, Chin-Ping Hu, Jan Hudec, Nikola Husarikova, Yuto Ichinohe, Jakub Kapus, Miroslav Kasal, Martin Koleda, Robert Laszlo, Chih-Hsun Lin, Tsung-Che Liu, Tsunefumi Mizuno, Kazuhiro Nakazawa, Hirokazu Odaka, Michal Pazderka, Ales Povalac, Maksim Rezenov, Martin Sabol, Kaustubha Sen, Miroslav Smelko, Petr Svoboda, Martin Topinka, Che-Chih Tsao, Tomas Urbanec, Ivo Vertat, Tomas Vitek, Chih-En Wu
Optics
Scanless quantum Fourier-transform mid-infrared spectroscopy for rapid high-sensitivity hyperspectral mapping
Paul Gattinger, Bettina Heise, Andreas W. Schell et al. (+3 more)
Fourier-transform infrared (FTIR) spectroscopy is a well-established technique for qualitative and quantitative chemical analysis. Classical FTIR systems rely, however, on direct mid-infrared (mid-IR) scan-based time-domain measurements of coherence functions; thus, the signal-to-noise ratio and measurement speed are constrained by design. In this paper, we demonstrate a scanless
quantum FTIR (sQFTIR) technique that exploits principles of metrology with entangled
photons to circumvent the limitations inherent to classical FTIR systems. The approach exploits the interferometric nature of the sensing paradigm and relies on frequency-domain measurements performed with a static, low-gain nonlinear interferometer. A robust reconstruction
algorithm is used to retrieve time-domain signals and reconstruct respective mid-infrared (mid-IR) spectra (3000$~$cm$^{-1}$ to 2380$~$cm$^{-1}$) from near-IR measurements (approx. 780$~$nm to 820$~$nm). The suggested sQFTIR protocol eliminates the need for optical delay scanning and leverages inherent mapping between the related domains. In the theoretical section, we evaluate the intrinsic signal-to-noise advantage of the proposed method over conventional scan-based time-domain measurements; a difference of 26.8 dB (factor of 21.8) is demonstrated. Building on the enhanced sensitivity of the scheme, we demonstrate rapid sQFTIR-based hyperspectral imaging with a spatial resolution of 12.3$~\mu$m and a spectral resolution down to 8$~$cm$^{-1}$. Hyperspectral mapping of human colon tissue, microplastics, and multilayer
polymer samples composed of polypropylene and ethylene vinyl alcohol yield high-quality single-pixel spectra with acquisition times down to 10$~$ms.
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All authors Paul Gattinger, Bettina Heise, Andreas W. Schell, Kristina Duswald, Markus Brandstetter, Ivan Zorin
Quantum Physics · Cross-listed from cs.AR
Fixed Point Exploration For CV-QKD IR QC-MET-LDPC Toward Hardware Implementation
Guilherme Vergne de Oliveira, Mauro Queiroz Nooblath Neto, Micael Andrade Dias et al. (+4 more)
High-speed LDPC decoding is a major bottleneck in CV-QKD and motivates hardware acceleration with fixed-point arithmetic. This work compares SPA, MSA, and NMS under a unified low-SNR fixed-point framework using common graph,
matrix, and quantization settings. Multiple formats are evaluated through FER, and average iterations. The results show that performance depends strongly on the interaction between decoder rule and numerical precision. SPA achieved the best overall performance. For reduced-complexity decoders, Q16.8 was the lowest consistent precision, with NMS outperforming MSA. Practically, SPA with Q8.4 offered the best balance between reliability and hardware efficiency for large-scale implementations.
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All authors Guilherme Vergne de Oliveira, Mauro Queiroz Nooblath Neto, Micael Andrade Dias, Francisco Revson Fernandes Pereira, Francisco Marcos de Assis, Valéria Loureiro da Silva, Nelson Alves Ferreira
Physics and Society
Where onshore wind meets forests: electricity system planning with ecologically graded forests
Muhammad Shahzad Javed, Marianne Zeyringer, Johannes Rahlf et al. (+1 more)
Onshore wind is expected to supply much of the growth in renewables, yet its expansion increasingly extends into forests, where wind generation and forest conservation act as competing
climate strategies for the same land. Net-zero system assessments typically treat forests homogeneously. Here, we grade forest exclusions by ecological value and couple them with a high-resolution net-zero electricity system model, representing onshore wind on forested and non-forested land as two distinct technologies. Applying a set of ecologically graded scenarios to Norway, we quantify how forest protection by its ecological value reshapes system design, the balance of onshore wind within and outside forests, and the robustness of these outcomes to complementary energy policy levers. At equal cost, the system treats forest as its preferred onshore resource, with forest wind comprising 60 to 90 percent of onshore capacity under permissive scenarios. Excluding forest raises system cost by up to 0.5 percent per GW of foregone forest wind, with diminishing returns as ecological criteria for forest exclusions tighten. Directing wind into forests does not compromise system efficiency, with onshore curtailment remaining largely unchanged at 3 to 8 percent. Land-use and technology decisions that appear independent may, in fact, interact, as
solar deployment reshapes the value of each wind resource and determines which is displaced from the generation mix. By quantifying the ecological value forgone per unit of forest onshore wind, this study makes explicit a trade-off that energy system modelling usually leaves implicit, providing a transferable basis for balancing the competing
climate strategies of protecting forests and sustaining wind expansion.
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All authors Muhammad Shahzad Javed, Marianne Zeyringer, Johannes Rahlf, Oliver Moen Snoksrud
Exactly Solvable and Integrable Systems
Real-Spectrum Darboux Limits at Multiple Spatial Roots of the Coupled Fokas-Lenells System
Muchen Dong and Lei Wang
We investigate Darboux constructions generated by multiple spatial roots of the coupled Fokas-Lenells system on a plane-wave background. Nonreal double roots give regular one-fold transformations, whereas real double and triple roots require directional real-spectrum limits. We classify the admissible projective null sets, derive the leading spectral corrections, and establish global regularity. A critical background relation additionally produces a persistent zero branch, leading to distinct nonlocal plateaus along
parabolic corridors, cubic level sets, and a characteristic line.
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Cosmology and Nongalactic Astrophysics
Comparing explicit likelihood and likelihood-free simulation-based inference for weak lensing cosmic shear
Simone Vinciguerra, Nicolas Martinet and Marco Gatti
Simulation-based inference (SBI) has become a major tool for extracting cosmological information from weak-
lensing (WL) surveys, particularly from non-Gaussian observables. We compare its two main paradigms: explicit likelihood inference (ELI), based on a Gaussian likelihood built from an emulator and covariance
matrix, and likelihood-free inference (LFI), which learns the likelihood directly from simulations using neural density
estimators. Using Gaussian random field mocks representative of the non-tomographic final Euclid data release, we analyse shear two-point correlation functions (shear-2PCFs), compressed with linear or non-linear methods, together with a fundamentally different map-level convolutional neural network (CNN) statistic, focusing on $\Omega_{\rm m}$ and $S_8$. We deploy posterior calibration diagnostics developed for LFI, including the test of accuracy with random points (TARP), showing that ELI becomes strongly miscalibrated under emulation inaccuracies or likelihood non-Gaussianity, whereas LFI remains well calibrated. These effects drive substantial disagreement between ELI and LFI, which largely vanishes once addressed. We further show that the compression scheme can significantly degrade ELI while leaving LFI largely unaffected. Although shear-2PCFs should capture all the information in Gaussian fields, finite compression and non-Gaussian likelihoods cause ELI constraints to differ by up to a factor of two from those inferred with the CNN, while the discrepancy drops to $\approx 30\%$ for LFI, underscoring the robustness of the deep-learning probe. Overall, our results indicate that in our simple setup, which neglects systematic biases, LFI provides a more robust and better-calibrated framework, while highlighting accurate non-Gaussian likelihood modelling and posterior calibration diagnostics as essential for future ELI analyses.
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Mathematical Physics
On the use of equilibrium models to describe dynamic adsorption regimes
M. Calvo-Schwarzwalder, A. Valverde, A. Cuesta López et al. (+3 more)
We present a column adsorption model that couples a Pseudo-First-Order (PFO) kinetic formulation with the Sips isotherm framework. Using a traveling wave approximation, we derive analytical solutions for specific operating conditions. Qualitatively, these solutions deviate significantly from their pure Sips counterparts: instead of a smooth, continuous increase in concentration at the column outlet, the PFO-Sips model predicts an abrupt, sudden breakthrough. We validate these analytical solutions against diverse experimental
datasets from the literature. The results reveal that the PFO-based model consistently underperforms compared to the original Sips formulation. Furthermore, this validation exposes fundamental inconsistencies within the PFO framework. We demonstrate that despite its widespread use in the literature for almost a century, the PFO model is inherently flawed and structurally unfit for describing column adsorption dynamics.
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All authors M. Calvo-Schwarzwalder, A. Valverde, A. Cuesta López, A. Cabrera-Codony, U. Thorat, T.G. Myers
Quantum Physics
Noise structuring in fixed-depth Trotter simulation: stationary channels and observable-level depolarization
G. L. Stavisskii, W. V. Pogosov, L. E. Fedichkin et al. (+1 more)
We analyze fixed-depth Trotter simulation as a method for structuring hardware noise in digital many-body dynamics. The number of layers is chosen using the largest endpoint time and is then kept fixed throughout the time scan, making the total noise dose approximately independent of the endpoint time. For local
stochastic faults, we show that, once propagated faults lose
memory of their insertion layer, the noisy
circuit factorizes into ideal
evolution followed by a stationary finite-depth binomial channel. In the dilute-layer limit, this channel reduces to a Poissonian exponential. The
memory time of a single fault is related to a Loschmidt echo. An important consequence is observable-level depolarization: for selected macroscopic observables at low to moderate noise levels, the stationary channel can act as an almost time-independent affine contrast correction, even though the full channel need not be depolarizing, which is crusial for error mitigation purposes. At short times, the same protocol produces a digital Zeno-like transient, in which a fixed number of noise opportunities competes with a vanishing coherent angle per layer. Our results also reveal limitations of naive zero-noise extrapolatin strategies based on oversimplified functions.
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All authors G. L. Stavisskii, W. V. Pogosov, L. E. Fedichkin, A. V. Lebedev
Quantum Physics
Variational non-gaussian approach to interacting spin-boson models
João Pedro Mendonça, Yao Wang and Krzysztof Jachymski
We apply a hybrid variational framework to interacting
spin-
boson Hamiltonians, targeting regimes where simulations are limited by the unbounded bosonic
Hilbert space and strong many-body correlations. The bosonic sector and
spin-
boson correlations are captured within a compact non-Gaussian variational
manifold, while the minimized
spin sector is obtained as the solution to an effective
spin Hamiltonian. Minimization is carried out inside a self-consistent energy-minimization loop, where variational parameters are minimized and the effective
Hamiltonian is solved via DMRG. The results are obtained without eliminating or truncating the photonic field. We
benchmark the method on the Dicke and Dicke-Ising models by comparison to converged
spin-
boson DMRG, finding accurate ground-state solutions with reduced bond dimension.
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Solar and Stellar Astrophysics
Probabilistic Stellar Age Estimation for Gaia XP Stars with NGBoost
Xiaokun Hou, Wenbo Wu, Gang Zhao et al. (+2 more)
Stellar age is a fundamental quantity for
Galactic archaeology, but reliable age estimation for large
stellar samples remains challenging. In this work, we develop an uncertainty aware NGBoost framework for
stellar age estimation using
Gaia XP-derived atmospheric parameters and chemical abundances. Different from the standard NGBoost model, we modify the loss function by incorporating the uncertainties of the training age labels. We further use a Monte Carlo strategy to quantify the influence of input-feature uncertainties on the predicted ages. The resulting model provides age estimates together with uncertainty estimates. Applying this framework to
Gaia XP
stars, we construct a
stellar age catalog containing 15,175,107
stars.
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All authors Xiaokun Hou, Wenbo Wu, Gang Zhao, Haining Li, Jingkun Zhao
Instrumentation and Methods for Astrophysics
gevolution 2.0: GPU-accelerated relativistic N-body simulations for cosmology
Julian Adamek and Øyvind Christiansen
High-performance computing is increasingly dominated by hardware acceleration using Graphics Processing Units (GPUs). To take advantage of this long-term trend, we implement a major overhaul of the parallelisation approach in the relativistic particle-mesh N-body code gevolution. The new version 2.0 of gevolution employs three layers of parallelisation: MPI for scalability on a distributed
memory system, shared
memory parallelisation on each MPI rank using OpenMP, and offloading all compute intensive tasks to GPUs using CUDA. The code also includes many new features that have been developed over the past years. We provide an overview of the code structure and show key performance
benchmarks. The public release of gevolution 2.0 can be found at https://github.com/gevolution-code/gevolution-2.0. We also release a GPU-ready version of the LATfield2 library which provides the parallelisation backend, available at https://github.com/gevolution-code/LATfield2.
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Materials Science
Informatics Modeling of High Tg Polymers: Assessing the Role of Processing versus Chemistry
Qinrui Liu and Scott R. Broderick
Despite the advances in structure-based modeling of
polymer properties, accurately predicting glass transition temperature (Tg) is still challenging for
polymers whose behavior is strongly influenced by intermolecular interactions and processing conditions. We previously developed a machine-learning model based on
polymer topological descriptors to predict Tg. The model performed well and was based solely on the chemistry and structure of the
polymer without any inclusion of processing parameters. In this work, we have extended that work by first applying that same model to a larger range of
polymers and second by integrating processing parameters into the feature set. The chemistry-based model still demonstrates consistent predictive performance for most
polymers, indicating that Tg is indeed primarily chemistry and structure driven and not strongly impacted by processing. However, several
polymers exhibited deviations between predicted and experimental Tg values. Detailed analysis reveals that these differences are related to strong intermolecular interactions and processing-dependent factors, particularly for
polymers prepared by solution casting and high temperature annealing. These results demonstrate that molecular
topology provides a strong foundation for Tg prediction; however, this approach also screens out those classes of
polymers for with processing conditions play an important role.
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High Energy Physics (Phenomenology)
Quantum numbers of excited $\Xi_c^\prime$ and $\Omega_c$ baryons and the $P$-wave $\Sigma_c$ spectrum
Xuan Luo, Shu-Wei Zhang, Hua-Xing Chen et al. (+1 more)
Heavy
quark effective theory (HQET) permits seven $P$-wave states in each of the $\Sigma_c$, $\Xi_c^\prime$, and $\Omega_c$
flavor-sextet sectors, yet the experimentally visible spectra differ strikingly among the three sectors. We show that strong decays, kinematic thresholds, and configuration mixing act as a dynamical filter between the underlying multiplet structure and the observed resonance spectrum. Using QCD sum rules for the masses and light-cone sum rules for the strong decays, we find that only four $\Sigma_c$, four $\Xi_c^\prime$, and five $\Omega_c$ states are sufficiently narrow to contribute to experimentally identifiable resonance structures. The four narrow $\Xi_c$ states, $\Xi_c(2882)$, $\Xi_c(2923)$, $\Xi_c(2939)$, and $\Xi_c(2965)$, and the four narrow $\Omega_c$ states, $\Omega_c(3000)$, $\Omega_c(3050)$, $\Omega_c(3066)$, and $\Omega_c(3090)$, exhibit similar mass-splitting patterns and provide spectroscopic anchors for a common $\lambda$-mode multiplet structure, supporting the successive assignments $J^P=1/2^-,3/2^-,3/2^-$, and $5/2^-$. We tentatively interpret $\Omega_c(3119)$ as a predominantly $\rho$-mode state with $J^P=3/2^-$. With this multiplet structure constrained by the $\Xi_c$ and $\Omega_c$ spectra, we predict four relatively resolvable $P$-wave $\Sigma_c$ states that may overlap within the observed $\Sigma_c(2800)$ and $\Sigma_c(2900)$ structures, providing concrete targets for future amplitude analyses.
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All authors Xuan Luo, Shu-Wei Zhang, Hua-Xing Chen, Hui-Min Yang
Quantum Physics
Sensing relativistic quantum fields with minimally perturbing local measurements
F. Daem, L. Ballesteros Ferraz, A. Zampeli et al. (+1 more)
We develop a framework for minimally perturbing local measurements in relativistic
quantum field theory, with the aim to sense local properties of the field in a non-destructive manner. The field properties are sensed by weakly coupled pointers and encapsulated in conditional expectation values dependent on a postselection of the field state. Our operational protocol uses causally admissible Kraus updates for the field, in line with recent relativistic measurement theories, keeping in mind restrictions related to “impossible measurements”. We illustrate our approach with three applications: a spacelikeness detector for causal-structure sensing, counting particle-creation densities in a supercritical potential and non-destructive discrimination between entangled states of the field and mixtures.
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All authors F. Daem, L. Ballesteros Ferraz, A. Zampeli, A. Matzkin
Optics
Femtosecond-to-millisecond holographic imaging of laser ablation dynamics
Shotaro Kawano, Keiichiro Toda, Miu Tamamitsu et al. (+3 more)
Femtosecond
laser ablation redistributes optically deposited energy across electronic, structural, mechanical, and thermal degrees of freedom over timescales from femtoseconds to milliseconds. However, these coupled processes are usually measured in separate temporal ranges and through different observables, limiting quantitative comparison between early transient dynamics, residual heating, and final morphology. Here we introduce pump-probe
holographic imaging that reconstructs amplitude- and phase-resolved optical fields across this full temporal range under matched imaging conditions. Applied to deep-ultraviolet femtosecond ablation of BK7 glass, the method captures the transition from early excitation and removal-stage dynamics to residual substrate heating and permanent modification. Differential phase analysis isolates sub-nanosecond
evolution of the transient ablating layer and microsecond residual heating after material removal. Above the ablation threshold, crater depth increases with fluence, whereas the residual thermal signal saturates, indicating that additional absorbed energy is preferentially partitioned into material removal and ablation-related processes rather than retained as substrate heat. These results identify fluence-dependent energy partitioning as a dynamical basis of low-heat-affected femtosecond processing and establish
holographic imaging as a route to tracking
laser-driven nonequilibrium material transformations.
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All authors Shotaro Kawano, Keiichiro Toda, Miu Tamamitsu, Haruyuki Sakurai, Kuniaki Konishi, Takuro Ideguchi
Fluid Dynamics
Transition to chaos in two-dimensional Rayleigh-Bénard convection: the role of the magnetic field
Francis F. Franco, Gabriel de T. Paula, Roman Chertovskih et al. (+2 more)
The impact of an externally imposed
magnetic field on numerical simulations of two-dimensional Rayleigh-Bénard convection (RBC) is investigated. Initially, the RBC model is examined in the absence of a
magnetic field to establish a baseline. Then, a background
magnetic field is introduced, and its influence on the transition to chaos is explored. For the purely hydrodynamic case and a range of the reduced Rayleigh number, the system exhibits traveling rolls which, after an attractor-merging crisis, give way to chaotic traveling rolls. Upon imposing a background
magnetic field, there is a notable increase in the occurrence of traveling roll dynamics. Furthermore, the presence of the
magnetic field favors the splitting/breaking of convective rolls, indicating a possible mechanism for transition to two-dimensional
turbulence, with the structure of the convection
cell being disrupted. A detailed analysis of the velocity field reveals that the collision between a saddle point and the center of a convective roll restores the system's original
topology, with two symmetric kinetic
vortices. During this collision, a
magnetic vortex splits in two as a result of a
magnetic reconnection. This behavior occurs intermittently in time.
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All authors Francis F. Franco, Gabriel de T. Paula, Roman Chertovskih, Dalton N. Oliveira, Erico L. Rempel
Statistical Mechanics
Large scale behavior in the Kuramoto-Sivashinsky equation: The Schwinger-Dyson route
Olivier Coquand
The present paper is a study of the large scale properties of the Kuramoto-Sivashinsky equation. By using a Schwinger-Dyson framework, we aim to provide a proof that the only solutions that can sustain a stable scaling in the infrared limit have a negative effective viscosity (in the Kuramoto-Sivashinsky sense) with a minimal set of hypotheses, thereby showing that this constitutes a general property of the wave equation that does not depend on a specific set of truncations of a renormalisation group flow, or limitations of a given numerical scheme for example.
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Materials Science
The Recurrent Structural Frameworks of Stable Inorganic Materials
Roee Asher, Nadav Moav and Lee A. Burton
The number of possible
crystal structures vastly exceeds the number realized among thermodynamically stable inorganic materials, suggesting that experimentally accessible structure space is organized around a limited set of preferred structural frameworks. Analysis of 23,160 structures on the thermodynamic convex hull identifies 6,820 distinct structural frameworks, of which 2,382 recur across multiple chemically distinct materials and are therefore classified as structural prototypes. Within a filtered
dataset, metallic systems exhibit particularly strong structural recurrence, with 6,270 materials grouped into 535 frameworks and 327 prototypes, while 5,557 ionic compounds occupy 1,704 frameworks and 696 prototypes. These results demonstrate that stable inorganic materials occupy a highly compressible region of structure space and establish a recurrence-based catalog of structural prototypes that provides an empirical measure of framework prevalence, enabling the relative likelihood of structural frameworks in future materials to be estimated from their recurrence among known compounds.
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Materials Science
Chemical filters for ultra-high-throughput materials screening and generation
Kinga O. Mastej, Panyalak Detrattanawichai, Hyunsoo Park et al. (+3 more)
Generative artificial intelligence is rapidly transforming materials design by enabling de novo exploration of immense chemical spaces. Yet a large proportion of AI-generated compositions remain implausible, violating established chemical principles, which limits the reliability and interpretability of generative materials design. Here, we introduce a chemical validity operator that recasts heuristic chemical rules as a configurable algorithmic prior for evaluating and guiding generative materials discovery. Built on the open-source SMACT package, a data-informed oxidation-state model exposes tunable thresholds, allowing users to interpolate continuously between permissive and conservative chemical constraints, while supporting both exploratory and conservative materials-design workflows. Benchmarking six state-of-the-art generative models for inorganic
crystals shows that most reproduce stoichiometry but under-represent realistic oxidation-state combinations, and that filtering removes compositions reliant on rarely observed oxidation states while preserving low-energy compounds near the convex hull. Beyond screening, the same operator can also serve as a reinforcement-learning reward, steering a latent
diffusion model towards chemically grounded compositions. By encoding chemical heuristics and observations, this work establishes a foundation for oxidation-state-aware generative models.
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All authors Kinga O. Mastej, Panyalak Detrattanawichai, Hyunsoo Park, Anthony Onwuli, Masahiro Negishi, Aron Walsh
Chaotic Dynamics
Beyond the Edge of Chaos: Stability-Expressivity Transfer in Reservoir Forecasting
Yao Du and Xingang Wang
The edge-of-chaos heuristic has long served as a guiding principle for designing reservoir computers, yet its relevance to machine performance remains elusive. Here, taking the spectral radius of the reservoir network as the control parameter, we show that the radius yielding the best
forecasting performance does not coincide with the Lyapunov edge of the isolated, teacher-forced, or closed-loop generative reservoir. By analyzing the collective dynamics of the teacher-forced reservoir, we find that the target dynamics are represented mainly by stable Lyapunov modes whose finite-time stability is strongly modulated by the input. This finding motivates a stability-expressivity transfer index, which balances the stability of these modes against their expressivity in representing the target. Across chaotic and quasiperiodic targets, and for both asymmetric and symmetric reservoirs, this index accurately identifies the optimal spectral radius for autonomous
forecasting.
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Statistical Mechanics
A Unified Discrete and Continuous Theory of Core-Halo Complexity Maximizers
Akshat Sharma
The maximization of statistical complexity has long been associated with the emergence of probability distributions lying between perfect order and complete disorder. While previous studies have shown that complexity-maximizing distributions exhibit a two-level structure in finite discrete systems, an analogous unified treatment for both discrete and continuous probability spaces has remained unavailable. In this work, we develop a general variational framework for a generalized statistical complexity constructed from Shannon and Renyi
entropies. We derive a common stationary equation governing both discrete probability masses and continuous probability densities and prove that every stationary solution necessarily possesses exactly two probability levels, establishing a universal core-
halo structure. We further demonstrate that the optimization problem reduces to a single multiplicity parameter and prove that the global complexity maximum is attained by the smallest admissible core, corresponding to a single dominant state in the discrete case and an infinitesimal core in the continuous limit. These results provide a complete analytical characterization of the complexity-maximizing distributions and reveal a common mathematical structure underlying complexity optimization in both discrete and continuous settings. The framework establishes a unified foundation for generalized statistical complexity with potential applications in statistical mechanics, information theory, and the analysis of complex systems.
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Medical Physics
Portable surrogate-free 4D MRI from standard fast multi-slice 2D MRI via implicit neural representations
Muheng Li, Xinyang Wu, Xia Li et al. (+5 more)
Four-dimensional MRI (4D MRI) characterizes respiratory organ motion, yet existing reconstruction pipelines are tightly coupled to specific acquisition platforms (e.g., non-Cartesian trajectories with self-gating, vendor-specific navigators, or external respiratory hardware), limiting broad adoption across diverse clinical and research settings, including low-field, open-bore, and non-supine imaging. We present SIMPLE-4D (Surrogate-free, IMplicit, PortabLE 4D MRI), a software-first portable workflow that operates entirely on reconstructed slices from standard fast multi-slice 2D MRI and requires no pulse-sequence modification, no non-Cartesian trajectory, no navigator, and no external hardware. SIMPLE-4D combines an acquisition-agnostic front end consuming standard 2D protocols, a surrogate-free variational motion encoder that extracts a compact motion code directly from each 2D slice, and a physics-aware continuous spatio-temporal reconstruction based on a hash-encoded implicit neural representation (INR) with a SIREN deformation network producing bidirectional cycle-consistent DVFs and motion-dependent Gauss-Legendre thick-slice quadrature. Bidirectionality yields a complete inter-frame motion model by composition, supporting downstream tasks such as dose accumulation without retraining. We validate the identical pipeline on two contrasting
datasets: a 1.5 T clinical bSSFP
dataset (5 volunteers, 3 sessions each) and a 0.5 T open-bore HASTE
dataset (5 volunteers, supine and upright). To our knowledge, this is the first per-frame 4D volumetric respiratory MRI reconstruction on a weight-bearing upright open-bore low-field scanner from reconstructed 2D Cartesian slices alone. On low-field data the INR template additionally acts as an implicit denoiser, yielding +132% SNR. Systematic ablations isolate each component's contribution.
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All authors Muheng Li, Xinyang Wu, Xia Li, Orso Pusterla, Philippe C. Cattin, Sairos Safai, Antony J. Lomax, Ye Zhang
Materials Science
Localized crystallization of Ce:YIG thin films on Si using CO2 laser annealing for integrated nonreciprocal photonic device applications
Xinran Ji, Junxian Wang, Tianchi Zhang et al. (+6 more)
Laser annealing (LA) technique has emerged as an effective method for localized crystallization of magneto-optical (MO) garnet thin films on
semiconductor substrates. However, no studies have explored the crystallization and magneto-optical (MO) properties of cerium-substituted yttrium iron garnet (Ce:YIG, Ce1Y2Fe5O12) thin films for integrated photonic device applications using LA technique. In this study, we provide a comprehensive investigation into the
laser annealing of Ce:YIG films deposited on SiO2 substrates and silicon nitride photonic waveguides for integrated nonreciprocal photonic device applications. Garnet phase was successfully observed in films grown on SiO2 substrates, and SiN waveguides with
laser annealing of sputtered Ce:YIG films on top of a
laser annealed Y3Fe5O12 seed layer. The magneto-optical (MO) properties of Ce:YIG films on oxidized Si substrates were found to be comparable to those prepared by rapid thermal annealing (RTA). A Mach-Zehnder Interferometer (MZI) type optical isolator based on Ce:YIG film on SiN was fabricated, exhibiting a saturation Faraday rotation of -2317.7 deg/cm and propagation loss of 188.2 dB/cm. Isolation ratio of 27.1 dB and insertion loss of 10.1 dB were achieved at 1552.7 nm wavelength.
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All authors Xinran Ji, Junxian Wang, Tianchi Zhang, Xuan Zhao, Di Wu, Zixuan Wei, Yizhi Chen, Jialong Wang, Lei Bi
Nuclear Experiment
First measurement of $\mathbf{\rm \Xi_{\rm c}^{0}}$ production in $\mathbf{Pb}-\mathbf{Pb}$ collisions at $\mathbf{\sqrt{\textit{s}_{\rm NN}}}$ = 5.02 TeV
ALICE Collaboration
The ALICE Collaboration reports the first measurement of the production of
prompt $\Xi_{\mathrm c}^{0}$
baryons in
nucleus$-$
nucleus collisions by analyzing data from $\mathrm{Pb}-\mathrm{Pb}$ collisions at $\sqrt{s_{\mathrm{NN}}}~=5.02~\mathrm{TeV}$. The production and transverse-momentum ($p_{\mathrm T}$) differential spectra of $\Xi_{\mathrm c}^{0}$ are particularly sensitive to the hadronization process and to strangeness production in the
quark–
gluon plasma formed in high-energy heavy-ion collisions. The $\Xi_{\mathrm c}^{0}$
baryons are reconstructed at midrapidity ($|y|<0.5$) in the transverse-momentum intervals $3<p_{\mathrm T}~<12~\mathrm{GeV}/c$ and $4<p_{\mathrm T}~<12~\mathrm{GeV}/c$ in the 0$-$10% and 30$-$50% centrality intervals, respectively. The
nuclear modification factor ($R_{\mathrm{AA}}$) reaches values up to 3 in the interval $3<p_{\mathrm T}~<4~\mathrm{GeV}/c$, which is the largest value measured so far for charm
hadrons. Model predictions are compatible with the measured $R_{\mathrm{AA}}$, while, in the measured $p_{\mathrm T}$ intervals, they underestimate the production yield as well as the measured $\Xi_{\mathrm c}^{0}/\mathrm{D}^{0}$, $\Xi_{\mathrm c}^{0}/\Lambda_{\mathrm c}^{+}$, and $\Xi_{\mathrm c}^{0}/\mathrm{D}^{+}_{\mathrm s}$ yield ratios.
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Quantum Physics
How the Quantum Sorites Phenomenon Strengthens the Bell Argument and How a Random-Matrix Collapse Dynamics Answers It
Malcolm Forster
Bell proved that no theory of pre-existing local values can reproduce the predictions of
quantum mechanics, but his proof leaves the culprit ambiguous: one may reject either of two independence conditions, Outcome Independence or Parameter Independence, and most commentators have found Outcome Independence the safer sacrifice. The first part of this paper presents, in a form adapted to
spin-1/2 particles in the singlet state, an argument (Forster 2014) that removes the ambiguity: using a chained family of experiments in which
quantum mechanics predicts an extreme pattern of correlations – the
quantum Sorites phenomenon – a contradiction is derived without ever assuming Outcome Independence. Under the resulting
theorem, anyone who holds that hidden variables could improve on the
quantum probabilities must give up Parameter Independence itself. That looks like a heavy price, because Parameter Independence appears to be protected twice over: rejecting it seems to put superluminal influences into spacetime, and its statistical shadow – the No-Signaling condition – is experimentally beyond reproach The second part of the paper shows that the price is payable. In the random-
matrix collapse dynamics proposed by Kryukov, measurement is a random walk of the
quantum state, and the hidden variable is not a stock of values fixed at the source but the random stream that drives the walk – like the stored random numbers of a computer simulation, with the measurement settings playing the role of seeds. In that framework Parameter Independence is false while Outcome Independence and No-Signaling are both true, and one can say exactly how the Sorites argument is blocked, why the violation involves no process propagating in spacetime, and why the influence of one wing's setting on the other wing's outcome – demonstrated here in a simulation – can never be used to send a message.
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Plasma Physics
Nonlinear Dynamics of Current-Carrying ELM Filaments: Spiral Vorticity, Rotation, and Velocity Suppression
Souvik Mondal, N Bisai, Abhijit Sen et al. (+1 more)
In this work, we investigate the nonlinear dynamics of isolated current-carrying edge-localized mode (ELM) filaments using a reduced electromagnetic fluid model in slab geometry. Numerical simulations show that unidirectional parallel current significantly suppresses radial filament velocity and reduces the outward propagation velocity by weakening the
curvature-driven interchange force. The reduction in radial velocity is found to follow a modified scaling relation, demonstrating that increasing current progressively weakens outward filament propagation. Analysis of the vorticity equation shows that the electromagnetic current source changes from a dipolar structure to a remarkable spiral pattern, and overcomes the conventional
curvature drive in the nonlinear phase. This current-driven source directly imprints its
topology on the vorticity field, resulting in spiral vorticity, enhanced angular momentum, increased rotational energy, and localized shear layers. The filament therefore undergoes a transition from a conventional propagating state to a rotationally self-organized electromagnetic structure. These findings demonstrate that parallel current acts as an effective electromagnetic vorticity source and provides new insight into the nonlinear dynamics of ELM filaments in tokamak edge
plasmas.
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All authors Souvik Mondal, N Bisai, Abhijit Sen, Indranil Bandyopadhyay
General Relativity and Quantum Cosmology
Angular momentum flux through post-Newtonian order for noncircular nonspinning black-hole binaries in Einstein-Maxwell-dilaton theory
Qi Tan and Peng-Cheng Li
We compute the instantaneous angular momentum flux from nonspinning black hole binaries in Einstein-Maxwell-dilaton theory for generic noncircular orbits up to relative first post-Newtonian order. Working in the Einstein frame and using the direct integration of the relaxed field equations approach, we construct the scalar, electromagnetic, and tensor gravitational fields in the wave zone and express the required source multipole moments in the center-of-mass frame. In addition to the leading $1/R$ radiative fields, we retain the next-to-leading $1/R^2$ terms in the wave-zone fields, which describe finite-distance corrections and do not contribute to the flux at null infinity. We obtain separately the scalar, electromagnetic, and tensor contributions to the angular momentum flux. The scalar and electromagnetic channels begin with dipole radiation, while the tensor channel begins at quadrupole order. Our results recover the quasicircular balance relation, the known general-relativistic limit, and the expected scalar- and electromagnetic-dipole suppression limits. Together with the previously known energy flux, these results provide the dissipative information required for future studies of orbit-averaged eccentric
evolution and waveform phasing in Einstein-Maxwell-dilaton theory.
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Quantum Physics
Unifying Charge-Learnability Transitions in Monitored \(U(1)\)-Symmetric Quantum Circuits through Informational Power of Local Measurement
Yi-Fan Gong and Dan-Bo Zhang
Charge-learnability transitions in monitored symmetric
quantum circuits reveal how local measurement records acquire sufficient information to infer a conserved charge. Here we extend charge learnability to probabilistic weak measurements, for which the measurement probability and measurement strength are independently tunable. We find that the learnability phase boundary is organized by the informational power of local measurement. We further introduce cross
entropy as a label-sensitive diagnostic that distinguishes unbiased, biased, and antibiased decoder variants. Finally, the exact record–label mutual information provides a decoder-independent
benchmark for the information fundamentally available for charge inference. Our results establish informational power of local measurement as a unifying principle for charge learnability under general monitoring protocols.
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