General Relativity and Quantum Cosmology
Fast Bayesian Inference for Long-Duration Gravitational-Wave Signals in 3G detectors
Anand S. Sengupta
Third-generation (3G) gravitational-wave detectors will observe binary-
neutron-
star inspirals for nearly a day, so Earth's rotation becomes part of the signal rather than a negligible correction. This destroys the usual separation between intrinsic and extrinsic parameters and creates a major computational bottleneck for
Bayesian inference. We show that the exact five-harmonic Jaranowski-Krolak-Schutz (JKS) decomposition restores the separation of the rotating
antenna amplitude response from the computationally expensive intrinsic waveform calculations. By sampling the intrinsic waveform on a frequency grid set by its phase
curvature and then applying error-controlled relative binning, likelihood evaluations for a 21.3-h signal are accelerated by O(10^4), making day-long 3G signal inference practical.
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Soft Condensed Matter
Molecular interfacial rheology: Lipid membrane shear viscosity
Zhi-Xun Xu and Amaresh Sahu
We develop a method to extract the shear viscosity of a lipid membrane from
equilibrium molecular dynamics simulations. The method characterizes the rheology of general interfacial systems embedded in three-dimensional media; we term it molecular interfacial rheology. In our simulations the planar
bilayer and surrounding water are confined between solid, parallel walls. Following Onsager's regression hypothesis, membrane and water fluctuations are assumed to relax according to the coupled continuum-mechanical equations governing the confined system—which predict that the membrane transverse velocity autocorrelation function (TVACF) decays exponentially, at a rate set by the membrane and water viscosities. The measured TVACF, however, exhibits damped oscillations followed by a slowly decaying tail. We reconcile these behaviors using the Mori–Zwanzig formalism, and extract the wavevector-dependent membrane viscosity from the time-integral of the TVACF. Results from theory and simulations agree over a decade of wavevectors, and extrapolating to long wavelengths yields shear viscosities ranging from 0.064 to 0.18 pN*us/nm across two representative single-component, fluid-phase
bilayers. Our results are corroborated by nonequilibrium simulations where a spatially varying in-plane body force is applied to lipid molecules, thus validating the framework of molecular interfacial rheology.
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Earth and Planetary Astrophysics
Dust Substructures and Line Perturbations driven by a Forming Planet in J16120
Anibal Sierra, Andrés F. Izquierdo, Paola Pinilla et al. (+18 more)
Hints of
planet formation have been independently reported within the gap of the disc around 2MASS J16120668-301027 from millimetre continuum, infrared, and H-alpha observations. In this work, we present new evidence for ongoing
planet formation based on Atacama Large Millimeter/submillimeter Array (ALMA) Band 7 observations, detecting 0.87 mm
dust continuum emission together with 12CO (J=3-2) and 13CO (J=3-2) line emission. Visibility modelling of the continuum data reveals an inner disc and two
dust rings peaking at 23 and 75 au. The continuum morphology is better reproduced by an eccentric disc model (e approximately 0.1) than by an axisymmetric disc. We further investigate the gas kinematics through modelling of the 12CO channel maps. The residual line-width map shows a localised increase in velocity dispersion at the position of a previously reported circumplanetary disc candidate (deprojected radius approximately 32 au, position angle approximately 170 degrees) and along its orbit. This signal is spatially coincident with kink-like features and a transition from sub-Keplerian to super-Keplerian velocities. In addition, the velocity residual map exhibits an arc-like structure extending outward from the
planet candidate, while the gas kinematics, despite substantial uncertainties, is consistent with inflow towards the candidate's orbital radius. The observed increase in velocity dispersion agrees with predictions from
planet-disc interaction simulations, which produce enhanced
turbulence both at the
planet location and along its orbital path. Taken together, the continuum morphology and gas kinematic signatures provide compelling new evidence for ongoing
planet formation within the disc gap.
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All authors Anibal Sierra, Andrés F. Izquierdo, Paola Pinilla, Kan Chen, Myriam Benisty, Laura Pérez, Teresa Paneque-Carreño, Carolina Agurto-Gangas, Jaehan Bae, John Carpenter, Luca Cieza, Dingshan Deng, Stefano Facchini, Camilo González-Ruilova, Nicolás Kurtovic, Aleksandra Kuznetsova, Carlo F. Manara, James Miley, Álvaro Ribas, Giovanni Rosotti, Miguel Vioque
Materials Science
Remote epitaxy beyond polarity
Ching-Tai Fu, Pei-Jan Hung, Xudong Li et al. (+21 more)
Remote epitaxy through a monolayer two-dimensional material-covered substrate establishes a crystallographic registry across the van der Waals (vdW) surface that enables the epitaxial growth, lift-off and transfer of single-crystalline films. A central belief in remote epitaxy is that the substrate facilitating the phenomenon must be a material with strong ionicity, as the interatomic electrostatic potential fluctuation in covalent and metallic materials is substantially attenuated by two-dimensional materials. Here, we show remote epitaxy is possible when the substrate is a metallic or covalently bonded material and experimentally demonstrate non-polar remote homo- and heteroepitaxy across a wide range of material systems, including both metals and
semiconductors. The achieved non-polar remote interactions are designed and engineered by harnessing substrate conductivity and vicinal surface step-edge density. These findings indicate that remote epitaxy is universal and applicable to ionic, metallic, and covalent materials, expanding its capabilities and stimulating a plethora of new fundamental scientific questions about the mechanism of remote epitaxy.
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All authors Ching-Tai Fu, Pei-Jan Hung, Xudong Li, Xiaolong Zhu, Yu Han, Sayantan Mahapatra, Zhiheng Zhao, Qingsong Fan, Xubing Wu, Qizhang Li, Chenxi Sui, Zirui Zhou, Ting-Hsuan Chen, Cheng-Hao Lei, Ivan Kuzmenko, Xiaobing Zuo, Byeongdu Lee, Alexander S. Filatov, Jeffrey R. Guest, Fengyuan Shi, Yuzi Liu, Hua Zhou, Yunfeng Shi, Po-Chun Hsu
Atmospheric and Oceanic Physics
Disentangling Internal and Forced Climate Variability with Convolutional Neural Networks using Multivariate Fields
Guillaume Gastineau, Elena Provenzano, Constantin Bône et al. (+2 more)
Long-term
climate data exhibit variations composed of internal and forced components. Internal variability arises from natural processes that could occur within a stable
climate. Forced variability, on the other hand, reflects
climate changes induced, for example, by anthropogenic greenhouse gas and aerosol emissions. Accurately distinguishing between these types of variability is crucial for attributing
climate fluctuations and understanding internal variability processes and impacts. In this study, we apply a U-Net convolutional network, a model commonly used in computer
vision, to separate forced and internal
climate variability from 1950 to 2022 using a multi-model
dataset. The
dataset includes multiple fields from five single-model initial-condition large ensembles. Cross-validation is conducted by training the U-Net using the data from the ensembles of four models, leaving out the data from one model to assess performance. Validation results yield errors ranging from 0.1{\deg}C to 0.4{\deg}C for the forced variability of local-scale monthly surface air temperature, which is no more than half the magnitude of external forcing. The U-Net achieves better performance than a simple approach based on a fourth-order
polynomial trend for estimating forced variability. The error is mainly due to insufficient sampling and poor agreement among the models, as the U-Net underestimates the warming for the model with the highest transient
climate sensitivity during validation. Performance is lower for variables like sea-level pressure and precipitation because of their low ratio of forced to internal variability. This framework might be enhanced by incorporating a larger multi-model
dataset in the training and validation.
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All authors Guillaume Gastineau, Elena Provenzano, Constantin Bône, Nicolas Lebas, Robert C. J. Wills
Quantum Physics
Fundamental Limits of Quantum Metrology Beyond Fixed Causal Order
Wenjie Wei, Yutong Li and Shengshi Pang
Quantum metrology with indefinite causal order (ICO) has attracted intense interest due to its potential to surpass the limitations of conventional fixed-order strategies. A key open question is whether ICO can fundamentally enhance asymptotic precision scaling. In this work, we bridge this gap for the estimation of a single parameter encoded in $N$ identical uses of a finite-dimensional
quantum channel. We first establish a universal Heisenberg-scaling upper bound for the full general ICO process-
matrix class and show that for
unitary channels its optimal
quantum Fisher information (QFI) coincides exactly with that of parallel strategies. For noisy channels, a structurally refined bound shows that channels restricted to the standard
quantum limit (SQL) under parallel strategies remain SQL-limited under general ICO strategies. Most significantly, an asymptotically tight (AT) bound is derived to close the remaining possibility of an asymptotic ICO advantage by showing that general ICO and optimal parallel strategies have exactly the same leading QFI coefficient in both the SQL and Heisenberg regimes. For the operationally motivated class of
quantum circuits with
quantum control of causal order, we further obtain an iterative constraint on finite-query precision whose asymptotic limit agrees with that of the AT bound. Our results clarify the ultimate role of indefinite causality as a metrological resource for
quantum channel estimation.
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High Energy Physics (Phenomenology)
Displaced Signals from Long-lived Particles in Neutrinoless Double Beta Decay
Patrick D. Bolton, Noor-Inès Boudjema, Frank F. Deppisch et al. (+2 more)
Much of the literature on neutrinoless double beta ($0\nu\beta\beta$) decay with light new-physics mediators focuses on invisible missing energy. We investigate the scenario in which a massive Majoron-like particle $\phi$ is produced on-shell during $0\nu\beta\beta$ decay and subsequently decays into visible final states after travelling a macroscopic distance. Specifically, we analyze the displaced energy deposition from $\phi$ decays into a
photon pair ($\gamma\gamma$), a
photon and a dark
photon ($\gamma\gamma_D$) and an electron-positron pair ($e^+e^-$). We demonstrate that the displaced decays modify the expected visible energy spectra and provide novel, distinct experimental signatures at current and upcoming $0\nu\beta\beta$ experiments, with the promise of improving the sensitivity of the standard invisible Majoron searches in $0\nu\beta\beta$ decay by more than two orders of magnitude. The relevant effective couplings can naturally arise in well-motivated ultraviolet-complete scenarios that conventional $0\nu\beta\beta$ decay searches cannot probe.
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All authors Patrick D. Bolton, Noor-Inès Boudjema, Frank F. Deppisch, Chandan Hati, Chayan Majumdar
High Energy Astrophysical Phenomena
Electromagnetic alignment and jet precession around supermassive black holes: Quasi-periodic oscillations in tidal disruption events
Pau Amaro-Seoane, Leif Lui, Alejandro Torres-Orjuela et al. (+1 more)
We evaluate quasi-periodic oscillations and jet formation in
tidal disruption events using the covariant formulation of electromagnetic angular-momentum transfer. General-relativistic frame-dragging tears apart misaligned transient
accretion flows, forming an isolated inner mini-disk. The accumulation of
magnetic flux on the event horizon powers a relativistic jet via the Blandford-Znajek mechanism. Because the
magnetic field anchors to the precessing mini-disk, the jet axis rotates, generating
geometric modulations in the observed X-ray and
radio fluxes. To ensure physical consistency with the force-free magnetosphere required to launch a Blandford-Znajek jet, we model the electromagnetic back-reaction using a split-monopole
magnetic field
topology. By performing a small-
spin expansion of the Noether current density over the event horizon, we derive a closed-form analytical reaction torque exerted by the electromagnetic field on the
accretion plasma. We evaluate the resulting kinematics to show that the electromagnetic back-reaction induces a retrograde precession of the mini-disk, coupling with the prograde Lense-Thirring precession to dictate the global oscillation frequency. We formulate explicit predictions for observable transient signals and predict a monotonic attenuation of the peak-to-trough flux ratio as the mini-disk aligns, as well as a specific frequency drift signature characterized by an initial lengthening followed by an asymptotic shortening of the time interval between consecutive
flares. We establish an analytical mechanism where
magnetic flux depletion stalls
alignment, predicting a constant residual modulation amplitude at late times. We formulate a methodology to extract the black hole
spin and the
magnetic flux density directly from the temporal derivatives of this predicted frequency drift, operating independently of spectral continuum fitting.
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All authors Pau Amaro-Seoane, Leif Lui, Alejandro Torres-Orjuela, Xian Chen
Quantum Gases
How dipolar interactions structure molecular droplets
Wiiliam Freitas, Panagiotis Giannakeas and Jan M. Rost
We investigate how dipolar interactions between microwave-shielded polar molecules structure the self-bound droplets formed under variation of the interaction strength. We identify the transition from droplets to
crystals as a finite-size first order transition. With droplet-ring states and transitional supersolid states we predict additional structure in the
crystal and droplet phases, respectively. To describe this strongly correlated regime, and in particular the reconfiguration of
quantum ground states, we design a variational Monte Carlo framework based on neural
quantum states. It is especially suitable to describe ground states and almost degenerate states with very different configurations. Moreover, one can easily determine the superfluid fraction. Our results reveal the sequence of finite-size structures through which dipolar interactions reorganize molecular droplets into
crystals.
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Physics and Society
Mitigating Disease Spread by Design in Refugee and IDP Camps
Giulia Zarpellon, Joseph Aylett-Bullock, Frank Krauss et al. (+1 more)
Disease spread represents an increasing challenge in refugee and internally displaced person (IDP) settlements. The movement and interaction of people within camps is influenced by their layout, which therefore has the potential to significantly affect disease spread. This work aims at creating a methodology to explore the potential effects of different camp layouts as mitigating factors in the spread of diseases within settlements. We showcase proof-of-concept experiments by leveraging the JUNE
agent-based epidemic model, discuss the kind of operational insights this methodology can facilitate, and provide a framework for future investigations.
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All authors Giulia Zarpellon, Joseph Aylett-Bullock, Frank Krauss, Miguel Luengo-Oroz
Mathematical Physics · Cross-listed from cs.LG
Variational Continuation for Double Pendulum Periodic Orbits
Leo Yao, Ziming Liu and Max Tegmark
We present a Hessian-based approach to numerically continue periodic orbits in dynamical systems. A loop (periodic orbit candidate) is parametrized as a
Fourier series; a loss function is defined based on the deviation of the loop from the physical differential equations. Unlike previous work relying on hand-derived Jacobians, our method automates the process by leveraging automatic differentiation, a common machine learning technique. The continuation direction can be determined by the flat directions of the loss landscapes (directions with zero
eigenvalues), making the search of periodic orbits efficient and guided. Our method is integrator-free, precisely initializes oscillations around unstable fixed points, and efficiently detects orbit family intersections and subharmonic bifurcations. As a demonstration, we present full continuations of periodic double pendulum oscillations from fixed points, showing bifurcations along orbit families and categorizing branches of periodic orbits. In particular, we find periodic orbits where both pendulum masses are never simultaneously at rest, which to our knowledge has been missing in the literature.
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High Energy Physics (Theory)
The Junction That Remembers: Infrared Response of Two Coupled SYK Majorana Systems
Ali Vahedi
Two strongly interacting Majorana systems of the Sachdev–Ye–Kitaev type, each with its own independent disorder, are joined by a link that is switched on in time. We ask how the infrared structure of the link is imprinted on the response and whether the system remembers how it was opened. At large $N$ the leading cross-correlation between the two systems is an exact product of two
equilibrium propagators and the switching profile; because the disorder is independent, no ladder dresses it. The link operator has scaling dimension one half, which gives its susceptibility a universal logarithm whose coefficient and phase we fix and verify numerically, while the gap of the coupled
equilibrium problem grows more slowly than the naive crossover estimate. Exact dynamics for up to twelve Majoranas per side show strong parity transfer and
entanglement several times the free-
fermion ceiling. The work done by the switch has a first-order part that does not depend on the switching time and a second-order part that grows in magnitude with it. Once the work is held fixed, the protocol dependence of the
entanglement, the link expectation value and a scrambling diagnostic nearly vanishes, and the small residuals do not depend on whether the protocols differ at low or at high frequency. These small systems have no infrared window, so they neither confirm nor exclude
memory at large $N$.
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Earth and Planetary Astrophysics
Contrasting C/O ratios in Uranus and Neptune from disequilibrium chemistry: A clue to distinct evolutionary pathways?
T. Briand, V. Hue, O. Mousis et al. (+4 more)
The formation of Uranus and Neptune remains poorly constrained largely due to uncertain deep elemental abundances. Carbon monoxide (CO), a disequilibrium species in the upper troposphere, provides an indirect constraint on the deep oxygen abundance. We investigate the deep O/H and C/O ratios of the ice
giants and their formation history by accounting for meridional variations in atmospheric structure and uncertainties in chemical kinetics. We extended a 1D thermochemical and
diffusion model into a pseudo-2D model by including latitudinal variations in key model parameters. The O/H ratio was inferred by matching the modeled upper-tropospheric CO mole fractions to observations, and combined with the deep carbon abundance to derive the C/O ratio. For Uranus, varying tropospheric methane alone yielded O/H $\sim [47-57] \times$ protosolar, whereas allowing $K_{zz}$ to vary expanded the range to O/H $\sim [62-177] \times$ protosolar. For Neptune, the corresponding ranges are O/H $\sim [182-215] \times$ protosolar and O/H $\sim [222-342] \times$ protosolar, respectively, supporting lower oxygen enrichment in Uranus than Neptune. Chemical-network uncertainties have a more modest effect, amounting to at most $\sim 10\%$ of the retrieved oxygen ranges, comparable to the uncertainty associated with the measured CO abundance on Neptune, but larger on Uranus. We computed C/O latitudinal ranges and found C/O $\sim [0.06-0.52]$ on Uranus and $\sim [0.02-0.12]$ on Neptune. Comparison with a protoplanetary disk model suggests different formation or evolutionary pathways for the two
planets. Our results highlight the dominant role of vertical mixing in constraining deep oxygen abundance and the importance of accounting for meridional variability and chemical uncertainties. This work also provides a framework for selecting the entry latitude of a future Uranus Orbiter and Probe mission.
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All authors T. Briand, V. Hue, O. Mousis, T. Cavalié, T. Benest Couzinou, A. Schneeberger, M. D. Hofstadter
Quantum Physics
Restricting the effects hides a nonphysical symmetry from every causal structure
Chon-Fai Kam
Real-amplitude
quantum theory is the subtheory of
quantum theory invariant under complex conjugation, and experiments in networks of independent sources have measured correlations above the real bound. We construct a theory on which the same conjugation fails complete positivity and still leaves every probability in the unit interval, and whose correlations are exactly those of its own conjugation-invariant subtheory in every causal structure, the bilocality scenario included. Its states are all the density
matrices, its effects are the operators every partial transpose of which is again a
quantum effect, and its operations are the completely PPT-preserving maps. The symmetrized subtheory simulates it once each source carries a reference frame rather than each system. One map therefore receives three different verdicts in three theories, so the
symmetry alone marks no boundary at all.
Quantum theory admits every effect its states permit, and no theory with that property can hide a
symmetry this way, so what sustains the separation measured in the network experiments is the absence of a restriction rather than any feature of conjugation. What does have a boundary is the class of theories whose correlations coincide with those of their symmetrized subtheory. We show that sectorial closure, meaning invariance of the effects and the operations under the
symmetry acting independently on each source, suffices for the absence of a gap under any finite group, and that it cannot be weakened on the effects. Fixing unrestricted states and conjugation makes the effects of this theory the largest the
symmetry admits and its operations the largest sectorially closed ones, so it is not one construction among several. Locating where sectorial closure fails, for a candidate effect set built from a fixed bound entangled state, is a finite computation on a single ray of effects.
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Cosmology and Nongalactic Astrophysics
Supernovae Unite: Host-Galaxy Mass Measurements of Type Ia Supernovae and Their Impact on Cosmology
J. Lee, R. Camilleri, T. M. Davis et al. (+22 more)
Current consensus suggests that Type Ia
supernova (SN Ia) brightnesses post light-curve standardization correlate with their host-
galaxy stellar masses, which must be accounted for to obtain accurate cosmological constraints. For example, Vincenzi et al. (2025) showed that different host-
galaxy stellar mass measurements for the same
dataset produce
redshift-dependent differences of order $\sim 0.01$ mag, large enough to appreciably shift cosmological constraints. We present internally consistent host-
galaxy stellar masses remeasured using aperture photometry and spectral energy distribution (SED) fitting for SN-Unite, which combines the spectroscopic Pantheon+ and the photometric Dark Energy Survey five-year (DES-SN5YR) samples into the largest SN Ia cosmology sample to date, with 2884 likely SNe Ia. We find that photometry and SED fitting choices shift SN-Unite Flat$w$CDM parameters well below statistical uncertainties. Our
stellar masses differ from the Pantheon+ data release partly due to a
redshift-dependent internal inconsistency within Pantheon+, while remaining largely consistent with the DES-SN5YR (DES-Dovekie) data release. When the Pantheon+ subsample of SN-Unite is combined with
Baryon Acoustic Oscillations (BAO) and
Cosmic Microwave Background (CMB) measurements, the significance for time-evolving dark energy increases from 3.4$\sigma$ to 4.0$\sigma$ based on the maximum a posteriori when our newly derived host-
galaxy stellar masses replace the Pantheon+ data-release host-
galaxy stellar masses, while DES-Dovekie remains virtually unchanged, consistent with the findings of Hoyt et al. (2026). By remeasuring the host-
galaxy stellar masses using a consistent framework throughout the whole sample, we improve the robustness of the SN-Unite cosmological constraints against systematic differences in host-
galaxy stellar mass measurements.
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All authors J. Lee, R. Camilleri, T. M. Davis, D. Rubin, K. Bechtol, L. Galbany, M. Sako, M. Sullivan, T. E. Müller-Bravo, D. Scolnic, M. Vincenzi, D. Brout, C. Lidman, A. Möller, P. Shah, M. Acevedo, P. Armstrong, B. A. Bassett, R. C. Chen, H. T. Diehl, J. Frieman, K. Grech, B. Popovic, B. O. Sánchez, B. E. Tucker
Strongly Correlated Electrons
Breakdown of Anomalous Hall Scaling in Dilute Kondo System
Arnab Bhattacharya, Prashant Singh, Ajay Kumar et al. (+4 more)
The confluence of strong electronic correlations and Berry
curvature-driven transport constitutes a largely underexplored frontier in
quantum materials research, particularly in systems where electronic correlations arise from flat-band physics rather than conventional $f$-electron states. Here, we report an intrinsic Berry
curvature driven anomalous
Hall transport in the dilute Kondo system Ru$_2$Mn$_{0.5}$Ti$_{0.5}$Ge, a non-$f$-electron Heusler
alloy hosting flat bands with van Hove singularity proximate to the
Fermi level. The anomalous
Hall response is strikingly non-monotonic, violating the
Fermi-
liquid scaling relation near the
magnetic transition and is restored only at low temperature, coincident with the onset of Kondo coherence. Ab initio calculations strongly establish that the Berry
curvature originates from the Kondo hybridization induced interplay of flat bands and
spin-orbit coupling mediated anticrossings at the
Fermi level. Our findings demonstrate that Kondo coherence of flat bands bears a profound impact on Berry
curvature associated ferroic responses, mandating a rigorous theoretical understanding of anomalous transport in the regime where reciprocal space
topology and strong correlations are intrinsically intertwined.
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All authors Arnab Bhattacharya, Prashant Singh, Ajay Kumar, Afsar Ahmed, Yaroslav Mudryk, I. Das, Anis Biswas
Quantum Physics
Compiling the 2D Fermi-Hubbard ground-state energy estimation algorithm for active volume quantum architectures
Harriet Apel, Athena Caesura, Carys Harvey et al. (+11 more)
As
quantum computing enters the early fault-tolerant era,
circuit compilation choices will increasingly depend on details of the underlying architecture rather than solely optimizing for generic proxies such as non-Clifford count. We present an active-volume-aware compilation of the ground-state energy estimation
algorithm for the two-dimensional
Fermi-Hubbard model using
quantum phase estimation and Trotterized time
evolution. The proposed compilation reduces the active volume across $L\times L$ square
lattices with $L=4$ to $20$, achieving up to a $3.9\times$ reduction over prior work optimized for non-Clifford cost. As a by-product of these compilation improvements, the resulting
circuits also achieve state-of-the-art Toffoli counts, with a ~$2\times$ reduction for the $L=20$ case. Lastly, the active volume architecture and recent execution scheduling advances provide a means of translating these reduction trends into runtime. This demonstrates the increasing importance of architecture-aware compilation for practical early fault-tolerant
quantum computing.
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All authors Harriet Apel, Athena Caesura, Carys Harvey, Sam Heavey, Angus Kan, Jessica Lemieux, Ryan Levy, Sam Pallister, Joseph Peetz, William Pol, Sukin Sim, William A. Simon, Mark Steudtner, Gideon Uchehara
Nuclear Theory
Spectator shadowing as the source of the breaking of NCQ scaling at RHIC-FXT and FAIR energies
Tom Reichert and Iurii Karpenko
The apparent scaling of the
elliptic flow of identified
hadrons with the number of constituent
quarks indicates the presence of
quark coalescence, and in turn suggests the presence of a deconfined state in heavy-ion collisions. Recent measurements at RHIC found a breaking of NCQ scaling at low energies and suggested that this marks the onset of partonic collectivity at higher energies. Here, we present a new framework
embedding the effect of spectator shadowing into the flow scaling relations. Using a toy model with an idealized
quark coalescence source and a ballistic Glauber model for the bypassing spectator, we demonstrate that the observed breaking is an effect of spectator shadowing.
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Quantum Physics
SAR and InSAR Change Detection with Quantum Generative Models
Samwel K. Sekwao, Shaunak De, Alexis Hocken et al. (+7 more)
Change detection in synthetic aperture radar (SAR) and interferometric synthetic aperture radar (InSAR) underpins disaster response, infrastructure monitoring and land-use enforcement. Detection is limited by the background
estimator, which conventionally forms a conditional expectation directly from observed pixel statistics and degrades where those statistics are sparse, including the regime produced by the heavy-tailed marginals of sub-meter-resolution radars. In this work, we integrate state-of-the-art satellite imagery with
quantum machine learning on IonQ trapped-ion-based
quantum processors. By replacing the empirical conditional with a
quantum circuit Born machine (QCBM)-sampled generative model in Copula space, we substantially improve change detection on sparse real-world images. On Capella Space satellite image acquisitions, the generative
estimator matches conventional methods when the observed statistics are adequate, and substantially outperforms them when they are not. Executing the trained model on IonQ trapped-ion based hardware reproduces the results of the ideal and noisy simulations and demonstrates up to par, or even better, performance with the classical state-of-the-art methods. For a SAR
dataset of an airport, QPU
circuit evaluations for both training and inference achieved a maximized filtered F1 score of 0.32, compared with 0.16 and 0.24 for the two classical baselines. For an InSAR
dataset of a volcanic lava flow, all three methods reached a maximum filtered F1 of approximately 0.66. These experiments demonstrate the feasibility of executing a QCBM-based background
estimator on trapped-ion hardware. We further demonstrate that the QCBM method successfully extends to interferometric coherence data, achieving performance comparable to classical approaches.
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All authors Samwel K. Sekwao, Shaunak De, Alexis Hocken, Scott Staniewicz, Evgeny Epifanovsky, Craig Stringham, Gordon Farquharson, Martin Roetteler, Panagiotis Kl. Barkoutsos, Jason Iaconis
Earth and Planetary Astrophysics
Evidence for LP 890-9d via Transit Timing Variations
Kevin B. Stevenson, Guangwei Fu, Kristin S. Sotzen et al. (+10 more)
LP 890-9, also known as SPECULOOS-2 and TOI-4306, is a nearby late-M
dwarf hosting two confirmed transiting rocky
exoplanets. We analyze 20 JWST/NIRSpec PRISM transits of LP 890-9b and LP 890-9c obtained as part of GO program 7073 and detect statistically significant transit timing variations (TTVs), with peak-to-peak amplitudes of ~17 s and ~35 s, respectively. Using analytic linear TTV theory, we find that the known two-
planet configuration cannot reproduce the measured TTV amplitudes or super-period, whereas three-
planet models provide substantially better fits. The best-fit configuration places the candidate third
planet, LP 890-9d, between
planets b and c, with an orbital period of ~4.4 days; however, the current data do not uniquely determine its orbital architecture, and periods spanning 4.0-6.9 days remain plausible. TESS is insensitive to transits of LP 890-9d and we find no evidence for the candidate in JWST observations, although the phase coverage (ranging from ~50% to ~80%) depends strongly on the candidate orbital period. Additional high-precision transit observations of LP 890-9b and LP 890-9c are needed to refine their TTV solutions and further constrain the orbital properties of the third
planet.
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All authors Kevin B. Stevenson, Guangwei Fu, Kristin S. Sotzen, E. M. May, Larissa Palethorpe, Jacob Lustig-Yaeger, Ted M. Johnson, Eric Agol, Katherine A. Bennett, Carlos Gascón, David K. Sing, Jeff A. Valenti, Hannah R. Wakeford
High Energy Physics (Phenomenology)
Chaos is Target-Blind in High-Energy QCD Evolution
Raktim Abir
Chaotic
evolution measures how rapidly nearby configurations separate, but the existence of such rapid
evolution does not by itself determine what physical information the
evolution actually carries. For fixed-coupling JIMWLK
evolution with fresh transverse-local, color-isotropic noise, we show that this distinction becomes exact - leading to a no go
theorem. At finite rapidity step and finite transverse regulator, the exact linearized update depends on the Wilson-line background only through local adjoint rotations of fresh color-isotropic noise. Once the past is conditioned upon, these rotations leave the complete local noise measure invariant, so the tangent process has the same probability law for any target ensemble evolved with the same regulated fixed-coupling dynamics, including dilute and saturated ensembles. After the exact global color-rotation mode is removed, the reduced tangent process found to have a positive leading Lyapunov exponent which indicate chaotic
evolution. Fixed-coupling JIMWLK therefor can be dynamically chaotic while its tangent-only statistics carry no information about the target ensemble. Spatially nonlocal noise however evades the argument because correlations between distinct sites leave relative Wilson lines in the conditional covariance.
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Earth and Planetary Astrophysics
JWST Excludes Exomoons Down to 0.1 Earth Radii Around a Rocky, Temperate Exoplanet
David Kipping
To date, even with JWST, it has not been possible to test for exomoons as small as the Moon. Only two reported searches for exomoons around bound
planets have been attempted with JWST, both of which relied on a single JWST transit. We suggest that the below expectation sensitivity to date is, in part, a product of the considerable intrinsic flexibility of the
planet+moon transit model when confronted with a single event, and the presence of unanticipated systematic noise. To test this, we present a search around the rocky, temperate-zone
exoplanet LP 890-9c using twelve JWST transits. We find no evidence for an exomoon but exclude $0.1R_{\oplus}$ moons to 95% confidence across the entire Hill region, representing by far the most sensitive search to date. Our limits exclude analogs to many real
Solar System moons, such as Europa, Rhea and Umbriel. However, we emphasize that the close-in orbit of LP 890-9c (0.04au) would make any moons larger than ${\sim}0.1R_{\oplus}$ unlikely to survive for many Gyr due to tides. Regardless, our study firmly establishes that JWST can indeed probe down to remarkably small moons. Further, we find that even a single transit can deliver impressive limits, with the exception of one epoch that is contaminated by red noise. However, by pairing it with just one cleaner epoch, the sensitivity recovers to a level indistinguishable from any other pairing, which bodes well for a potential second JWST transit of Kepler-167e.
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High Energy Physics (Phenomenology)
Inelastic from the Other Side: Xenon Excitation Signals in Light of the LZ High-Recoil Event
Guanhua Gu, Lingfeng Li, Shao-Song Tang et al. (+1 more)
The LUX-ZEPLIN (LZ) experiment recently reported a single event consistent with a
nuclear recoil of $E_{\rm NR}\sim248\pm23\,(\mathrm{stat})\pm23\,(\mathrm{syst})$~keV in an extended-energy search. We study the accompanying inelastic-xenon channel, $\chi+\Xe\to\chi+\Xe^{*}$, which provides a complementary test of DM interpretations of such high-
recoil events. Using the non-relativistic effective-field-theory (NREFT) framework with shell-model
nuclear-transition inputs, we compute the inelastic-xenon rates for representative scenarios including inelastic dark matter and accelerated DM populations. We also simulate their S1–S2 responses, with detector modeling validated against public LZ data. The
nuclear de-excitation adds an electromagnetic component shifting the signal toward the electronic-
recoil band and, in some cases, toward clustered backgrounds from isotopes. We therefore construct a schematic, physics-motivated background model and perform a simplified statistical analysis. For many
benchmarks, the inelastic-xenon rate is $\mathcal{O}(0.1)$ of the elastic rate or below, suggesting that substantially larger exposures are required before this companion channel becomes observable. Our results illustrate the importance of isotope-induced background structures in the extended-energy region and extend the phenomenology of inelastic-xenon signatures to a wider range of DM scenarios.
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All authors Guanhua Gu, Lingfeng Li, Shao-Song Tang, Yongheng Xu
Quantum Gases
Fluctuations of a Photon Bose-Einstein Condensate Coupled to a Reservoir: Describing Coherence Properties in a Free-Energy Model
Martin Weitz, Andreas Redmann, Riccardo Panico et al. (+4 more)
Photons are mutually nearly noninteracting particles, so thermalized
photon ensembles are commonly obtained not from direct particle-particle-interactions but rather from contact with matter, which can constitute a reservoir for the
photon gas. We develop a theory model for
photons in a material-filled (e.g.
liquid dye) optical microcavity, with the aim to study the fluctuation properties using a free-energy description for noninteracting
photons coupled to a reservoir of material electronic excitations. To begin with, we use a single mode description for the condensate. For a small relative size of the material reservoir, corresponding to the canonical regime, condensate number fluctuations are small, and the derived free energy landscape takes the usual Mexican-hat shaped form such that spontaneous
symmetry breaking occurs. In contrast, for a large relative size of the reservoir, corresponding to the grand canonical regime, fluctuations become as large as the average particle number. We show that the resulting free energy landscape acquires a bowl-shaped form, with a single minimum at the origin. Thus, a macroscopic occupation of the ground state (i.e., Bose-Einstein condensation) in the absence of spontaneous
symmetry breaking is expected. We also provide a model for the treatment of a
photon gas trapped in a box-shaped potential with spatially distributed coupling to a reservoir. The model predicts, for example, a statistically fluctuating pattern of islands with long-range coherence, resembling transient microcondensates.
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All authors Martin Weitz, Andreas Redmann, Riccardo Panico, Leon Kleeblank, Kevin J.H. Peters, Frank Vewinger, Julian Schmitt
Astrophysics of Galaxies
Rapid quenching and early gas depletion in the core of a galaxy protocluster at z=2.2
C. D'Eugenio, H. Dannerbauer, A. Naufal et al. (+6 more)
Understanding how
galaxy evolution is affected in forming high-z overdensities is a major open question in modern astrophysics. Here, we present the average properties of the quiescent
galaxy population recently identified in the core of the Spiderweb protocluster at z = 2.16. By stacking observations from the Hubble Space
Telescope (HST; F160W imaging and G141 grism spectroscopy), the James Webb Space
Telescope (JWST; PaBeta narrowband imaging), and the Atacama Large Millimeter/submillimeter Array (ALMA; 1.2 mm
dust continuum imaging), we constrained their ensemble
star formation history (SFH), residual
dust-obscured
star formation, and cold gas mass, respectively. The inferred average SFH indicates steady
stellar mass growth, with progenitor SFRs consistent with those of massive Halpha emitters (HAEs) in the same structure. This is followed by rapid quenching, on average 500 Myr prior to observation. No significant age differences are found between active
galactic nucleus (AGN) hosts and non-AGN systems. We find weak PaBeta emission for 80% of the sample, yet with
dust-obscured
star formation rates consistent with quiescence in all but one source (ID 443) excluded from the sample. Our
galaxies remain individually and globally undetected in the
dust continuum, yielding an average gas fraction fgas= Mmol/Mstar<7%, consistent with previously reported gas depletion trends with
stellar mass observed in neighboring HAEs. We thus find the Spiderweb protocluster to host a sizable population of gas-depleted, massive quenched
galaxies in its core, likely descending from main-sequence
galaxy progenitors and building the first elements of the red sequence in this high-z forming cluster.
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All authors C. D'Eugenio, H. Dannerbauer, A. Naufal, J. M. Pérez-Martínez, Y. Koyama, P. G. Pérez-González, Y. H. Zhang, T. Kodama, K. Daikuhara
Disordered Systems and Neural Networks
Connecting heterogeneous dynamics with local entropy
Jun Wu, Walter Kob, Yujie Wang et al. (+1 more)
Establishing a robust and physically interpretable link between static structure and heterogeneous relaxation dynamics remains a fundamental challenge in glass physics. Here, we introduce a weighted pair-
entropy descriptor based on the conventional two-body excess
entropy. For this, we multiply the integrand used to calculate the excess
entropy by a weight function that is directly related to the length scale of the pair correlation function. This multiplication does not affect the contribution of the short range order to the local excess
entropy, but allows to take into account the structure present on intermediate distances, i.e., the medium-range order. For a canonical two-dimensional Lennard-Jones glass former, the resulting descriptor exhibits a strong correlation with particle-level dynamical propensity at long times (multiples of the alpha-relaxation time), with a maximum structure–dynamics correlation reaching about 0.9, substantially outperforming the predictive power of the conventional local pair excess
entropy. These results demonstrate that incorporating a physically motivated structural length scale into
entropy-based descriptors markedly enhances their predictive power while preserving physical interpretability. Our findings provide a simple and general framework for investigating structure–dynamics correlations in glass-forming systems.
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All authors Jun Wu, Walter Kob, Yujie Wang, Zhen Zhang
Applied Physics
Thermoelectric properties of metal-semiconductor percolation composites
Oleksandr Porubaniyi, Sergii Tomko, Mihailo Cherkez et al. (+2 more)
We analyze thermoelectric response of composite materials comprising homogeneous
semiconductor hosts with randomly distributed metallic inclusions. We demonstrate that the properties of such materials are strongly affected by the percolation transition (with background conductivity). We show that in vicinity of percolation threshold, the power factor and the thermoelectric figure of merit strongly depend on both the concentration and arrangement of inclusions. Finally, we identify promising regimes for enhancing the power factor in realistic composites.
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All authors Oleksandr Porubaniyi, Sergii Tomko, Mihailo Cherkez, Viktor Podolskiy, Radion Cherkez
Solar and Stellar Astrophysics
ROCKETS I: Investigating the Impact of the Rocket Effect on Two Nearby Young Open Clusters Encased in Infrared Bubbles
R. Arun, G. Maheswar, Annapurni Subramaniam et al. (+5 more)
We introduce ROCKETS (Rocket-driven Cluster Kinematics & Triggered
Star-formation), a
Gaia based programme investigating kinematic fingerprints of
stellar feedback or rocket effect in young
star forming regions. We analyse two young clusters with O-type
stars enclosed by mid-infrared bubbles, Collinder 69 and IC 1396 as a methodological demonstration on two nearby
benchmark regions. Co-moving candidates are selected within an astrometric ellipse defined by the median and median absolute deviation of Class I/II YSOs with
Gaia data. For each
star, we compute a relative proper-motion angle (RPMA) relative to the ionising source. In both regions the RPMA distribution shows a strong excess at RPMA $<15^{\circ}$, corresponding to sources moving away from the respective ionising sources. We quantify this using the Rocket Effect Index (REI), finding $\mathrm{REI}\simeq 1.1$ for Collinder 69 and $\mathrm{REI}\simeq 1.7$ for IC 1396. When considering only Class I/II YSOs, the REI of both regions increases to $\mathrm{REI}\gtrsim 10$. Velocity-structure analysis of the sample shows that the RPMA $<15^\circ$ subset has stronger positive pairwise expansion than the full co-moving population, providing additional support for the rocket effect. The outward-moving
stars are not uniformly distributed; instead, their position angles are strongly anisotropic and preferentially aligned towards the bright-rimmed clouds.
Gaia colour-magnitude diagrams show no strong age offset between sources moving outward and literature cluster members. The observed kinematic signatures support feedback-driven acceleration of gas and triggered
star formation preferentially towards higher density regions of expanding bubbles due to the rocket effect.
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All authors R. Arun, G. Maheswar, Annapurni Subramaniam, Piyali Saha, T.P. Sudheesh, B. Shridharan, Blesson Mathew, Akhil Krishna R
Solar and Stellar Astrophysics
Energy Partitioning at the Termination Shock
Judit Szente, Bart van der Holst, Gabor Toth et al. (+1 more)
We show new results of a global 3D magnetohydrodynamic (MHD) simulation of the Boston University outer heliosphere model where we used a newly developed approach that distributes the non-adiabatic shock heating among the cold
protons, electrons, and pickup-ions (PUIs), while maintaining total energy conservation of all ions (cold
protons and PUIs) and electrons. In our previous simulations ( E.S. Bair et al. 2025; B. van der Holst et al. 2026), all non-adiabatic shock heating was channeled to the cold
protons, resulting in a too large temperature jump at the termination shock (TS) for the thermal
solar wind. Using a new methodology we improved the simulation results with respect to the temperature jump observed at the TS by Voyager 2 (V2) spacecraft. Our simulations approached the observed jump conditions of a factor 10–20 in the cold
solar wind temperature V2 measurements, and we obtain improvements in the simulation results relative to the data. Because we directly estimate in this way the distribution of non-adiabatic heating at the TS, we have the opportunity to study the physical process of heating cold
plasma and PUIs in the TS. The results show that having almost 100% non-adiabatic shock heating going towards PUIs at the TS reproduces the jump conditions observed along the V2 trajectory. This information is key to understanding the physical processes that shape the heliosphere. As shown by M. Opher et al. (2020), PUIs significantly change the shape of the heliosphere, for example, the presence of hot PUIs results in a deflated inner heliosheath. Our work provides the architecture of how energy partitioning at shocks in kinetic simulations (J. Giacalone et al. 2021) can be utilized in global MHD models.
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All authors Judit Szente, Bart van der Holst, Gabor Toth, Merav Opher
Earth and Planetary Astrophysics
Enabling Metallicity Measurements of M-dwarf Microlensing Lenses out to the Galactic Bulge
Jiyuan Zhang, Gregory Green, Weicheng Zang et al. (+2 more)
We demonstrate that
metallicity becomes identifiable for M-
dwarf microlensing lenses out to bulge distances when multi-band lens photometry is combined with the angular Einstein radius, thereby defining the photometric–microlensing
metallicity method. The cool atmospheres of M
dwarfs contain abundant molecules, whose broad absorption bands make their positions in an optical–NIR color–absolute magnitude diagram sensitive to
metallicity. The angular Einstein radius provides the mass–distance constraint needed to infer the lens absolute magnitude, while the intrinsic M-
dwarf locus and reddening vector are non-parallel in color–color space, allowing the lens extinction and intrinsic color to be inferred simultaneously from its multi-band photometry, thereby recovering the lens intrinsic position in the
metallicity-sensitive color–absolute magnitude diagram. The method requires three-band lens photometry spanning roughly the R, Z, and K bands, making it particularly well suited to Roman through its high-resolution F062, F087, and F213 imaging. With the planned Roman
Galactic Bulge Time-Domain Survey (GBTDS) observations plus an additional $\sim$8 hr of F062 imaging per field ($\sim$40 hr in total) roughly a decade after Roman launch, host
metallicities could be measured for $\sim$150 planetary systems under the GBTDS yield forecast, with a typical $1\sigma$ precision of $\sim$0.25 dex from our mock-recovery analysis. Applied homogeneously to GBTDS microlensing events with and without detected
planets, the method would enable the first measurement of the occurrence–
metallicity relation for cold low-mass
planets beyond the snow line, constrain the low-
metallicity cutoff for their formation, and extend occurrence–
metallicity studies into the inner
Galaxy.
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All authors Jiyuan Zhang, Gregory Green, Weicheng Zang, Hongjing Yang, Shude Mao