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Friday 12 June

Soft Condensed Matter

Interfacial mass transfer resistance at fluid-fluid interfaces

Hyeongjoo Row, Brandon J. Wallace, Joshua B. Fernandes et al. (+2 more)

Complex chemistry in nano- and microscale compartments is often governed by how quickly reagents transit a fluid-fluid interface. Mass transport across interfaces is commonly modeled by assuming local equilibrium, enforcing continuity of chemical potential across the interface. While adequate at large scales, this approximation may break down at the microscale, where interfacial processes can become rate-limiting. Here, we extend linear irreversible thermodynamics to describe nonequilibrium interfacial mass transport. We identify an interface-limited regime, in which transport is governed by interfacial resistance and exhibits exponential relaxation. Combining microfluidic and spectroscopic techniques, we introduce an experimental technique that explores this regime and provides a direct measurement of the interfacial mass transfer coefficient. For a model system consisting of acetonitrile transport across a surfactant-stabilized water-oil interface, we obtain an interfacial transport coefficient ${M \sim 7\,{\rm nm/s}}$. These results establish interfacial mass transfer resistance as a governing mechanism in microscale transport and provide a framework to predict, control and measure mass transport in multiphase systems at microscale.
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All authors Hyeongjoo Row, Brandon J. Wallace, Joshua B. Fernandes, Kevin R. Wilson, Kranthi K. Mandadapu

Quantum Physics

Quasilinear Equivalence Checking for Detector Error Models

Mathys Rennela

A Detector Error Model (DEM) is a structured representation of error mechanisms in quantum circuits, which has gained popularity in quantum compilation pipelines for its ability to capture fault-tolerance at a circuit level. It lists error mechanisms as instructions targeting detectors and observables, specifying for each physical fault channel the probability that the fault fires, the detectors it triggers, and the observables it flips. In this paper, we develop an equational theory for DEMs, with its associated categorical semantics. We present a sound, terminating, confluent rewriting system for DEM terms, formulating it as a symmetric monoidal theory (a PROP) over the Giry monad. We prove that every DEM term has a unique normal form, which can be computed efficiently in quasilinear time $O(k|E|\log|E|)$, where $|E|$ is the number of instructions and $k$ bounds the size of a target set. This provides a complete set of invariants (via Tanner graphs) for structural DEM equivalence. We provide the first static decision procedure for DEM equivalence, with rigorous correctness guarantees. It is complete (decides full decoder-equivalence exactly) for non-adaptive quantum error correction (QEC) pipelines, and scales to a sound and applicable decision procedure for partially-adaptive circuits (lattice surgery, distributed QEC, ...) without suffering exponential overhead. We discuss its application to the verification and optimisation of quantum compilers.
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High Energy Physics (Theory)

Primal Bootstrap for Pion Scattering at Large-N

Sebastiano Bocchia and Alessandro Vichi

We introduce a basis for tree-level meromorphic scattering amplitudes suitable for describing pion scattering in the large-N limit. The basis is constructed as linear combinations of Lovelace-Shapiro-like amplitudes with varying Regge slopes and intercepts. The resulting amplitudes satisfy by construction the fundamental requirements of analyticity, crossing symmetry, and Regge behavior. We analyze their behavior in specific kinematical regimes, including the high-energy fixed-angle limit. We also show that finite linear combinations of our basis elements need not violate unitarity. Nonetheless, because unitarity is not imposed by construction, we enforce it a posteriori by requiring positivity of the partial-wave decomposition. This condition can be formulated as an optimization problem and solved numerically. The solutions to this primal bootstrap problem yield meromorphic amplitudes that satisfy all the aforementioned constraints. We compare several observables with the bounds obtained from the dual positivity conditions and show that our family of amplitudes spans the full allowed parameter space. With appropriate modifications, this method can be extended to construct amplitude families for broader applications.
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Astrophysics of Galaxies

From THESAN-ZOOM to JWST: Predicting ionizing photon escape and the rise of UV-bright reionization sources

Zebedee Summerfield, William McClymont, Sandro Tacchella et al. (+14 more)

Understanding the sources and evolution of cosmic reionization remains a central challenge in astrophysics, with the escape of ionizing Lyman-continuum (LyC) photons from early galaxies representing a major uncertainty. In this work, we use more than 35,000 galaxy realisations from the THESAN-ZOOM cosmological radiation-hydrodynamic simulations to identify indirect diagnostics of the LyC photon escape fraction ($f_\mathrm{esc}$) and the LyC photon escape rate ($\dot{N}_\mathrm{ion,esc}$) across the redshift range $z=3-16$. We train random forest regression models using these diagnostics to predict both quantities. We present four models: two trained with the full set of simulation-derived indicators to predict $f_\mathrm{esc}$ and $\dot{N}_\mathrm{ion,esc}$, and two restricted to observables accessible to JWST photometric surveys. We find the 10-to-100$\,$Myr star-formation rate ratio ($\mathrm{SFR}_{10} / \mathrm{SFR}_{100}$) and the gas-to-stellar mass ratio ($M_\mathrm{gas} / M_*$) to be the strongest diagnostics of $f_\mathrm{esc}$, suggesting a strong relationship between ionizing photon escape and gas clearing through bursty star formation. In contrast, rest-frame UV ($1500 \, \r{A}$) absolute magnitude ($M_\mathrm{UV}$) dominates $\dot{N}_\mathrm{ion,esc}$ prediction. Motivated by the strong predictive power of $M_\mathrm{UV}$, we combine observed UV luminosity functions with derived $\dot{N}_\mathrm{ion,esc} - M_\mathrm{UV}$ relations to construct histories of reionization. These are consistent with observational constraints, avoiding the recently reported crisis in the ionizing photon budget. Our analysis suggests that the bulk of reionization occurred rapidly after $z \approx 8$, driven by UV-bright galaxies, with the $M_\mathrm{UV} < -17$ populations providing the dominant contribution.
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All authors Zebedee Summerfield, William McClymont, Sandro Tacchella, Aaron Smith, Rahul Kannan, Enrico Garaldi, Ewald Puchwein, Xuejian Shen, Josh Borrow, A. Lola Danhaive, Laura Keating, Gabriel Maheson, Parth Mehrotra, Charlotte Simmonds, Amanda Stoffers, Mark Vogelsberger, Oliver Zier

High Energy Astrophysical Phenomena

Linear Gravitational Wave Memory Through the Window of Core-Collapse Supernovae

Colter J. Richardson, Anthony Mezzacappa, Haakon Andresen et al. (+1 more)

Low-frequency gravitational waves ($\lessapprox$ 50 Hz) from core-collapse supernovae are becoming more important for current and future gravitational wave studies. This frequency region is dominated by the global morphology of the explosion and the anisotropic emission of neutrinos from the event. This paper serves as a brief review of both theory and detection (prospects) for gravitational waves in the low-frequency region. We discuss the generation of the linear gravitational wave memory sourced from neutrino emission and show results from an example 15 $M_{\odot}$ Solar metallicity progenitor. We also discuss the detection of the linear gravitational wave memory in current detectors, utilizing a combination of a linear predictive filter and matched templating. Finally we will discuss detection prospects in future detectors such as Cosmic Explorer, Einstein Telescope, the Laser Interferometer Space Antenna, and the Lunar Gravitational-wave Antenna.
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All authors Colter J. Richardson, Anthony Mezzacappa, Haakon Andresen, Michele Zanolin

High Energy Physics (Experiment)

Measurement of the muon neutrino charged-current cross section with SND@LHC

The SND@LHC Collaboration: D. Abbaneo, S. Ahmad, R. Albanese et al. (+162 more)

We report a measurement of the muon neutrino charged-current (CC) interaction cross section on tungsten using the electronic detectors of the SND@LHC experiment at the CERN Large Hadron Collider. The analysis uses proton–proton collision data at a centre-of-mass energy of $\sqrt{s} = 13.6$ TeV, corresponding to an integrated luminosity of $68.6 ~\text{fb}^{-1}$ collected during LHC Run 3 in 2022 and 2023. A total of 31 $\nu_\mu$ CC candidates are selected against an expected background of $5.0 \pm 1.1$ events, consistent with a signal expectation of $24^{+10}_{-9}$ events. The signal strength is measured to be $\hat{\mu} = 1.09^{+0.72}_{-0.37}$, and the combined muon neutrino and anti-neutrino CC cross section on tungsten is determined to be $\sigma(\nu_\mu + \bar{\nu}_\mu) = (37^{+24}_{-12})\times 10^{-35}~\text{cm}^2$ at a median energy of $228$ GeV. In addition, a calorimetric measurement of the hadronic energies of the neutrino candidate events is performed, making use of calibration data from dedicated test-beam campaigns.
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All authors The SND@LHC Collaboration: D. Abbaneo, S. Ahmad, R. Albanese, A. Alexandrov, F. Alicante, F. Aloschi, K. Androsov, L.G. Arellano, C. Asawatangtrakuldee, M.A. Ayala Torres, N. Bangaru, C. Battilana, A. Bay, A. Bersani, C. Betancourt, D. Bick, R. Biswas, A. Blanco Castro, V. Boccia, M. Bogomilov, D. Bonacorsi, W.M. Bonivento, P. Bordalo, A. Boyarsky, S. Buontempo, M. Buzio, T. Camporesi, V. Canale, A. Celentano, D. Centanni, F. Cerutti, A. Cervelli, V. Chariton, A. Chiuchiolo, K.-Y. Choi, S. Chuethamchan, F. Cindolo, M. Climescu, G.M. Dallavalle, N. D'Ambrosio, D. Davino, R. De Asmundis, P.T. de Bryas, G. De Lellis, M. de Magistris, G. Del Giudice, G. De Marzi, A. De Roeck, S. De Pasquale, A. De Rújula, A. Di Crescenzo, C. Di Cristo, A. Di Mattia, C. Dinc, I. Dionisov, R. Donà, O. Durhan, D. Fasanella, O. Fecarotta, R.A. Fini, A. Fiorillo, N. Funicello, R. Fresa, W. Funk, G. Galati, K. Genovese, A. Golutvin, E. Graverini, L. Guiducci, A.M. Guler, V. Guliaeva, G.J. Haefeli, C. Hagner, J.C. Helo Herrera, E. van Herwijnen, S. Ilieva, S.A. Infante Cabanas, A. Infantino, A. Iuliano, R. Jacobsson, A.M. Kauniskangas, E. Khalikov, S.H. Kim, Y.G. Kim, G. Klioutchnikov, M. Komatsu, S. Kuleshov, H.M. Lacker, I. Landi, O. Lantwin, F. Lasagni Manghi, A. Lauria, K.Y. Lee, K.S. Lee, W.-C. Lee, W. Lerner, M. Liebsch, V.P. Loschiavo, A. Marrone, S. Marcellini, M. Majstorovic, F. Mei, A. Miano, A. Mikulenko, M.C. Montesi, D. Morozova, L. Mozzina, F.L. Navarria, W. Nuntiyakul, K. Obayashi, S. Ogawa, M. Ovchynnikov, G. Paggi, M. Pentella, A. Perrotta, N. Polukhina, F. Primavera, A. Prota, A. Quercia, S. Ramos, A. Reghunath, F. Ronchetti, N. Rossolino, T. Rovelli, O. Ruchayskiy, T. Ruf, Z. Sadykov, V. Scalera, W. Schmidt-Parzefall, O. Schneider, D. Schoerling, G. Sekhniaidze, A. Serban, N. Serra, M. Shaposhnikov, T. Shchedrina, L. Shchutska, H. Shibuya, C. Silano, G.P. Siroli, G. Sirri, T. E. Smith, G. Soares, J. Y. Sohn, O. J. Soto Sandoval, M. Spurio, A. Tarek, J. Tesarek, I. Timiryasov, V. Tioukov, B. Turk, E. Ursov, G. Vankova-Kirilova, G. Vasquez, V. Verguilov, N. Viegas Guerreiro Leonardo, C. Vilela, R. Wanke, S. Yamamoto, Z. Yang, C. Yazici, S.M. Yoo, C.S. Yoon, E. Zaffaroni, J. Zamora Saá

Soft Condensed Matter

Percolation of a rod-like particle in a static bed of spheres: trapping and passing

Juan C. Petit, Julio M. Ottino, Richard M. Lueptow et al. (+1 more)

We numerically investigate percolation of independent frictionless glued-sphere rod-like particles under gravity through a disordered static bed of larger spheres. We identify two distinct regimes: a trapping regime, where rods stop after percolating a limited distance in the bed and a passing regime, where rods percolate continuously with constant mean velocity. The transition between these regimes is governed by the length of the rod and the geometrical trapping threshold for spherical particles based on the rod diameter and the minimum pore throat diameter defined by three touching large spheres. The percolation velocity for all rod geometries, including the single sphere limit, collapses onto a single curve when scaled with the gravitational acceleration and the bed sphere diameter. The results also demonstrate that short rods percolate nearly twice as fast as long rods due to the geometric constraints associated with the disordered pore structure of the static bed. Consequently, long rods are more susceptible to trapping via specific contact configurations with the bed spheres, which differ from those for short rods. These results reveal how shape anisotropy introduces dynamical constraints and thresholds in granular percolation, with implications for predicting segregation in mixtures of non-spherical particles.
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All authors Juan C. Petit, Julio M. Ottino, Richard M. Lueptow, Paul B. Umbanhowar

Statistical Mechanics

Generic long-range correlations in conserved nonequilibrium mixtures

Jessica Metzger, Yariv Kafri, Mehran Kardar et al. (+1 more)

We study correlation functions in conserved nonequilibrium mixtures, including multi-temperature systems and non-reciprocal field theories. The corresponding linear theory is short-ranged, and nonlinearities are irrelevant in the renormalization-group sense. Nonetheless, we find that these nonlinearities generate long-ranged three-point correlations in the isotropic disordered phase. Our analytical predictions, which are based on a phenomenological theory, are confirmed by numerical simulations of Brownian colloids in contact with thermal baths at different temperatures. Dangerously irrelevant nonlinearities in nonequilibrium mixtures thus offer a new route to long-range correlations, supporting the hypothesis that such correlations are not the exception but the rule out of equilibrium.
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All authors Jessica Metzger, Yariv Kafri, Mehran Kardar, Julien Tailleur

Disordered Systems and Neural Networks · Cross-listed from q-bio.NC

Prospective Coding and Path Integration Emerge as Equilibrium Solutions of Self-Organizing Neural Networks with Firing-Rate Adaptation

Facundo Emina and Emilio Kropff

Continuous Attractor Neural Networks (CANNs) traditionally rely on pre-wired recurrent connectivity to model spatial representations, path integration, and anticipatory dynamics. However, the biological mechanisms through which this structured connectivity emerges via learning remain relatively unexplored. This work presents a theoretical framework revealing how continuous attractor connectivity and its computational properties self-organize through Hebbian plasticity, firing-rate adaptation, and global inhibition. We show that translationally invariant inputs naturally drive the emergence of stable, Gaussian-profiled feedforward weights. Crucially, anticipatory dynamics arise spontaneously within these feedforward architectures, shifting the activity bump forward without requiring recurrent excitatory collaterals. This predictive shift can be linearly amplified across multilayer networks, consistent with anticipatory activity observed in the superficial layers of the entorhinal cortex. Furthermore, introducing recurrent interactions allows the network to learn connections capable of self-sustaining a moving bump of activity. Finally, by modulating the network with an external, time-varying baseline current that encodes speed, the system adjusts its intrinsic velocity to function as a precise unidirectional path integrator. Ultimately, this study suggests that prospective coding and path integration are not manually engineered features, but rather naturally co-emergent properties of a single self-organizing competitive network.
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Earth and Planetary Astrophysics

Hydrogen and Helium Dissolution, Outgassing, and Loss in Evolving Sub-Neptune Magma Oceans: Examining Demographic Features and Radius Evolution

Yao Tang, Jonathan J. Fortney, Laura K. Schaefer et al. (+1 more)

Sub-Neptunes' molten interiors are expected to accommodate large quantities of volatiles, potentially altering their radius evolution. Previous studies have examined this effect in isolation with simplified evolution modeling, often assuming idealized interior and atmospheric conditions. To address this limitation, we introduce SEAMIST, a unified evolution model for sub-Neptunes and super-Earths that self-consistently combines, for the first time, interior structure, cooling, rock/iron solidification, boil-off, photoevaporation, H/He dissolution, and atmospheric composition. SEAMIST considers both a partially soluble case, in which hydrogen partitions into the magma ocean with a fraction set by mantle-envelope boundary conditions, and a fully miscible case, in which hydrogen may fully dissolve into the magma ocean at high temperatures. We identify a novel catastrophic boil-off mechanism, triggered by a positive feedback between hydrogen outgassing and mass loss that can operate billions of years after disk dispersal. In partially soluble models, the impact of H/He dissolution on radius evolution is modest. This contrasts with previous expectations, as we find that increasing hydrogen abundance from outgassing enhances mass-loss efficiency, counterbalancing volatile replenishment from the rock/iron interior. Fully miscible hydrogen, in contrast, significantly enhances envelope survival especially around low-mass stars. Overall, at intermediate to low masses, mass-radius curves from partially soluble models match observed distributions. The fully miscible case predicts a pronounced radius peak and excess planets around low stellar masses that appear inconsistent with current observations, although it reproduces the observed radius “cliff" near 4$R_\oplus$ at higher masses. Our results suggest that high metallicity may explain the cliff, although alternatives cannot be entirely ruled out.
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All authors Yao Tang, Jonathan J. Fortney, Laura K. Schaefer, Peter Gao

Atmospheric and Oceanic Physics

ENSO and the Temperature of the North Equatorial Counter Current: An Ensemble Study

David John Webb

An ensemble study using the CESM climate model is used to investigate the response of the atmosphere to changes in sea surface temperatures along the path of the North Equatorial Counter Current. The results support those of a previous study which concentrated on a single run, confirming the sensitivity of deep convection in the central Pacific to the temperature of the counter current, and its impact on the Hadley Circulation, the Southern Oscillation and the equatorial winds in the Pacific. A comparison with the ECMWF ERA5 data, finds that the atmospheric reanalysis fields show similar correlation with the temperature of the counter current.
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High Energy Physics (Phenomenology)

In search for signals of the $D\bar{D}$ bound state $X(3700)$ from study of the $B^+ \to D^+ D^- K^+$, $B^0 \to D^+ D^- K^0$ and $\Lambda_b \to D^+ D^- \Lambda$ reactions

Xiu-Lei Ren, Hai-Peng Li, Wei-Hong Liang et al. (+2 more)

We perform a theoretical study of the $B^+ \to D^+ D^- K^+$, $B^0 \to D^+ D^- K^0$ and $\Lambda_b \to D^+ D^- \Lambda$ reactions by looking at the production mechanisms, with special emphasis in the final state interaction of the charmed mesons, which gives rise to the $X(3930)$, coupling strongly to $D_s\bar{D}_s$, and another state that we call $X(3700)$, coupling strongly to $D \bar D$ that qualifies as a $D \bar D$ bound state. The combined study of all these reactions shows that the final state interaction responsible for the production of these resonances is more important in the $B^+ \to D^+ D^- K^+$ reaction than in the $\Lambda_b \to D^+ D^- \Lambda$ one. We have taken this into account and shown that normalizing the $D^+ D^-$ mass distributions to the same value at the peak of the $\psi(3770)$ production, the two mass distributions are quite different in a range of 10 MeV above the $D^+ D^-$ threshold, with a value about an order of magnitude bigger for the $B^+ \to D^+ D^- K^+$ reaction than for the $\Lambda_b \to D^+ D^- \Lambda$ one. The $D^+D^-$ mass distribution by itself also shows an enhancement of about one order of magnitude in the presence of the $X(3700)$ with respect to a calculation where this resonance is absent. We make a call to measure these magnitudes in the coming LHCb upgrades, which would bring great support to the existence of the bound $D^+ D^-$ state.
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All authors Xiu-Lei Ren, Hai-Peng Li, Wei-Hong Liang, Chu-Wen Xiao, Eulogio Oset

Astrophysics of Galaxies

Nebular_AGN: A CIGALE module for fitting active galactic nucleus emission lines

Hao Zhang, Patrice Theule, Veronique Buat et al. (+3 more)

Aims. The increasing discovery of high-redshift AGNs in recent years imposes more stringent requirements on spectral analysis tools for deriving the properties of AGNs and their host galaxies from emission-line diagnostics. To address this need, we develop a new module for the popular SED-fitting tool Code Investigating GALaxy Emission (CIGALE), the [nebular_AGN] module, which enables the efficient and flexible simulation and fitting of emission lines originating from the broad-line regions (BLRs) and narrow-line regions (NLRs) of AGNs, and allows the estimation of the physical properties of these regions. Methods. We use the spectral synthesis code Cloudy to construct the database for the new module. Based on the X-ray and accretion disk continua implemented in CIGALE, we generate the incident radiation fields of the models. We then adopt the AGN geometry and dust settings implemented in CIGALE to define a flexible set of physical parameters for the gas clouds, thereby producing a comprehensive database for the [nebular_AGN] module. Results. We benchmark the [nebular_AGN] module using a quasar composite spectrum, an empirical metallicity calibration, and observational data from X-ray-selected AGNs. Our module can approximately reproduce the majority of quasar emission-line profiles, cover the key emission-line ratios observed in AGN samples, and provide an assessment of their physical properties. For specific combinations of parameters, the metallicity derived by our module is consistent with the empirical formula. We further compare our models with other photoionization models used to simulate AGN NLR emission, and perform a line-sensitivity study to identify the most effective diagnostic lines for each parameter in our module. Finally, we confirm that the dust attenuation law plays an important role in SED fitting.
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All authors Hao Zhang, Patrice Theule, Veronique Buat, Denis Burgarella, Estelle Pons, Mederic Boquien

Lattice Field Theory

Zeros of the partition function for 12 flavor QCD

Anas Saleh, Michael Hite, Diego Floor et al. (+1 more)

We consider a four dimensional $SU(3)$ lattice gauge theory with 12 staggered fermions having identical masses and an unimproved action. Using sets of plaquette distributions for various inverse bare couplings $\beta$, we reconstruct the density of states with the Ferrenberg -Swendsen method and calculate the zeros of the partition in the complex $\beta$ plane with bare quark masses $m_q$ = 0.02, 0.06, 0.08 and 0.1 for hypercubes of linear size $L$= 4, 6, 8, 10, and 12. Our hypothesis is that there is a line of first order transitions in the $(m_q,\beta)$ plane ending at a second order phase transition. We expect this transition to be in the 4D Ising, mean field, universality class. We fit the $L$ dependence of the zeros with the lowest imaginary part using two ($y = bL^{-d}$) and three ($y = a + bL^{-d}$) parameter fits. For $m_q$ = 0.02 the results provide strong support for a first order phase transition ($d=3.98(6)$, and $a$ statistically compatible with 0). The results also indicate, with less statistical significance for $m_q=0.06$, that the three other masses are above the critical value $m_q^c$. In addition, we suggest that the infinite volume gap for the lowest zero $a$, can be represented as $a\simeq A(m_q-m_q^c)^{B}$ with $m_q^c\sim 0.05$ and $B\sim 1$. Given that there are only three data points with significant error bars, it is difficult to rule out the mean field value $B=3/2$. Combining this result with spectroscopic results by Jin and Mawhinney, indicates that the gap with real axis (Lee-Yang edge) scales roughly like $m_\sigma ^2$, where $m_\sigma $ is the mass of the $0^{++}$ scalar which is also the lowest excitation.
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All authors Anas Saleh, Michael Hite, Diego Floor, Yannick Meurice

High Energy Physics (Theory)

On the gauge-invariant dynamical charges and densities of the 1-instanton solution

C. A. da Silva and L. A. Ferreira

We study the gauge-invariant dynamically conserved charges, and their corresponding densities, for instanton solutions of Yang-Mills theories in four dimensional Euclidean space, for the gauge group $SU(2)$. Those charges were constructed in [1,2] through the integral equations of Yang-Mills theory, using techniques on generalized loop spaces. We use the integral non-Abelian Gauss law to evaluate the gauge-invariant flux of the magnetic and electric non-Abelian fields through spherical surfaces centered at the origin of the instanton solution. From such a flux, we define gauge-invariant charge densities by considering the charge within an infinitesimal spherical shell of radius $r\equiv\sqrt{x_i \, x^i}/\lambda$, with $\lambda$ being the parameter of the instanton solution, defining its size, and $x_i \, x^i = (x^1)^2 + (x^{2})^2 + (x^{3})^2$. We discuss the issue of the reparameterization invariance of the charges and densities, and show that the magnetic and electric fluxes for the instanton and anti-instanton, at $r=1$ and $x^4 = 0$, $x^4$ being the Euclidean time, are non-zero and observable. Our results give an interesting picture of the internal structure of the instanton, and may be important for the properties of the Yang-Mills $\theta$-vacuum.
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Earth and Planetary Astrophysics · Cross-listed from cs.CV

Improving Lunar Topography with Deep Learning Schrödinger Bridges

Matthew Repasky, Erwan Mazarico, Michael K. Barker et al. (+3 more)

Increasing the resolution of planetary topography models can enable a better understanding of surface processes and geomorphology; however, existing analytical super-resolution methods are expensive and difficult to apply at large scales. Generative models provide the tools to learn complex relationships within data and can be applied at scale due to hardware accelerators and parallelization. We present a diffusion-based Schrödinger Bridge (SB) generative modeling approach for lunar topography super-resolution, connecting the distribution of low-resolution topography to that of high-resolution topography, incorporating physically-constraining optical imagery. Our approach is inspired by existing Shape-from-Shading methods, which improve a priori low-resolution topography by using optical images at the target resolution. We train SBs on a novel dataset of rendered lunar topography, emulating optical imagery from the Lunar Reconnaissance Orbiter Narrow Angle Camera. The result is a flexible approach for topography super-resolution which can provide pixel-level uncertainties in the reconstruction.
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All authors Matthew Repasky, Erwan Mazarico, Michael K. Barker, Stefano Bertone, Terence J. Sabaka, Yao Xie

Strongly Correlated Electrons

Open Wilson chain numerical renormalization group approach to steady-state non-equilibrium quantum transport

Anand Manaparambil and Frithjof B. Anders

The numerical renormalization group (NRG) approach was developed to identify and quantify different equilibrium regimes of quantum impurity systems (QISs) with unprecedented accuracy by a tailored finite size representation. Out of equilibrium, the steady-state density operator is not of the Boltzmannian form but one that is determined by the imposed boundary conditions. We extend the NRG to the nonequilibrium setting by augmenting each Wilson site with a reservoir, whose coupling functions are calculated via a continuous fraction expansion in order to recover the continuum limit exactly. The nonequilibrium parameters such as a finite bias as well as a finite temperature gradient enters through the Bloch-Redfield tensor (BRT), whose zero eigenvector gives the steady-state density operator. We used the resulting open chain full density matrix (OC-FDM) approach with an effective single lead description to investigate the charge and spin transport through a quantum dot (QD) under finite bias and temperature gradient. The influence of lead asymmetry and an external magnetic field on the transport properties are also studied. For completeness, we have also investigated local properties of the QD, such as charge fluctuations and find excellent agreement with real-time quantum Monte Carlo (RT-QMC) data. The OC-FDM approach was able to explore Kondo energy scales as low as $T_K/D \approx 10^{-8}$ in the non-equilibrium regime, as well as show convergence with the established equilibrium benchmarks, such as a quantitative agreement with full density matrix numerical renormalization group (FDM-NRG) and Fermi-liquid scaling at small bias and temperature. Owing to the effective single lead description, a single OC-FDM data point takes orders of magnitude less time on a standard laptop, compared to other state-of-the-art numerical methods.
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High Energy Physics (Phenomenology)

The unintuitive SU(3) flavor and chiral limits of hadron resonances

José Ramón Peláez, Pablo Rabán and Jacobo Ruiz de Elvira

Contrary to naive expectations, poles used to define hadron resonances rigorously in the physical world may not evolve continuously to become degenerate in the SU(3)$_F$ and chiral limits of QCD. Instead, other shadow poles, usually ignored, may be the ones that degenerate and characterize the resonances in these limits. This feature is general, and we illustrate it first with the simple and familiar light-vector mesons, followed by the much-discussed light-scalar case. Their shadow poles and their degeneracy are found using the QCD low-energy effective theory unitarized to one loop.
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High Energy Physics (Phenomenology)

Efficient calculation of exclusive diffractive cross sections at the EIC and LHeC with the Sartre event generator

Tobias Toll, Dipan Ghosh and Abhinav Srivastav

We present a new version of the Sartre event generator for exclusive diffraction at small xP in the colour dipole model, for $ep$ and $e$A scattering at the EIC and the LHeC as well as ultra-peripheral $pp$, $p$A, and AA collisions at RHIC and the LHC. Sartre stores the first and second moment of the interaction amplitudes in lookup tables which are then used for efficient event generation. There are many possible combinations of processes in Sartre, with different initial state nuclear targets and different final state vector mesons or real photons. We also want to implement different versions of the dipole model: with and without non-linear saturation effects, with and without nucleon hotspot substructure. A long-standing bottleneck for simulating all possible exclusive processes has been the production of lookup tables, which take a few CPU-year for each combination, necessitating the use of computing farms. The calculation also involves integrations of rapidly fluctuating integrands, which may cause numerical glitches which takes much effort to smoothen out. In this paper we present a solution to these issues, by presenting a new numerical calculation which improves the efficiency in the table production by 3-4 orders of magnitudes. This enables us to produce lookup tables for any process that we may be interested in, in a few hours. The new calculation does also not exhibit numerical glitches. We provide novel predictions for the EIC and the LHeC using the new version of Sartre.
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Quantum Physics

No classical particle limit for massless quanta

Riccardo Falcone and Simon Fuchs

We investigate whether relativistic massless classical particles may emerge as the classical limit of massless quanta. To address this question independently of any specific dynamics, environment, or pointer basis, we develop an axiomatic and purely kinematical framework for the coarse-graining approach. In this formulation, a candidate classical phase space is taken as the outcome space of a POVM subject only to minimal classicality and covariance under the relevant spacetime symmetry group. Applying this framework to the Poincaré group, we prove a no-go theorem for massless particles: the covariance requirement is incompatible with the operational conditions for classicality. The theorem leaves open field-like limits of massless quanta, for example the emergence of electromagnetic or gravitational fields, while ruling out classical massless particles, such as classical photons or gravitons.
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Plasma Physics

Parametric instabilities of the inhomogeneous near SOL tokamak plasma, driven by the coupled effect of the high harmonic fast wave and of the ion and electron temperatures gradients, and anomalous heating of the near SOL ions

V. V. Mikhailenko, V. S. Mikhailenko and Hae June Lee

Electrostatic parametric instabilities in the inhomogeneous near-SOL tokamak plasma, driven by the combined action of a high-harmonic fast wave (HHFW) with a frequency near the 30th ion-cyclotron (IC) harmonic and electron and ion temperature gradients, are investigated numerically. The results indicate the parametric decay of the HHFW into a HHIC (Bernstein) wave and HHIC quasimode. The instability is found to exist within a finite wavelength range of the HHFW. The development of the parametric HHIC quasimode decay instability leads to the onset of parametric turbulence accompanied by anisotropic ion heating, with the ion heating rate across the magnetic field significantly exceeding that along the magnetic field.
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Computational Physics

Spin disorder competing with positional symmetry breaking governs the metal-insulator behavior in oxide paramagnets

Jia-Xin Xiong, Xiuwen Zhang and Alex Zunger

Numerous transition-metal oxides have low-temperature, long-range-ordered antiferromagnetic (AFM) states that are generally insulating, and high-temperature, disordered paramagnetic (PM) phases. The latter can be either insulating (predicted here for NaFeO3), or metallic (predicted here and previously observed in NaOsO3). Similar distinctions have been traditionally affected in strongly correlated models by the value used for Coulomb repulsion U. Here we show an alternative, strong-correlation-free (U=0) view suggesting that the distinction between insulating and metallic PM phases is governed by the competition between local magnetic moment disorder and the polymorphous distribution of off-center atomic displacements. Such parameter-free, energy-lowering symmetry breaking density functional calculations provide a framework for understanding metal-insulator behaviors across different quantum materials in terms of measurable local structural and magnetic parameters.
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Geophysics

Towards unified Geophysical Data Requirements for Magnetic Navigation (MagNav)

Regupathi Angappan, Kimberly Moore and Sriharsha Thoram

Magnetic Navigation (MagNav) has emerged as a vital alternative Positioning, Navigation, and Timing (PNT) solution, leveraging Earth's magnetic field for robust navigation in GPS/GNSS-degraded or denied environments. Despite its potential, the successful deployment of MagNav is currently hindered by the lack of standardized, high-fidelity geomagnetic reference maps. Existing datasets, primarily designed for geological exploration or academic research, do not meet the distinct operational requirements of navigation systems regarding spatial resolution, error quantification, and global accessibility. This paper initiates a community-focused dialogue on future geophysical data requirements for MagNav, grounded in extensive real-world flight trials. We distinguish between two primary use cases with divergent data needs: Operational MagNav, which requires globally consistent, queryable, and uncertainty-aware datasets for field deployment, and MagNav R&D, which demands comprehensive access to raw survey data to foster innovation. We provide a prioritized set of recommendations for future data requirements, including the development of cohesive, merged datasets, the inclusion of localized 3D uncertainty estimates, and the expansion of the World Magnetic Model (WMM) core field model to spherical harmonic degree 13 to improve consistency. Finally, we emphasize the strategic necessity of designated test ranges to validate these requirements and ensure the operational robustness of MagNav infrastructure.
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Cosmology and Nongalactic Astrophysics

Impact of non-Gaussian likelihood on cosmological constraints from the thermal Sunyaev–Zel'dovich power spectrum: a simulation-based inference analysis

Licong Xu, Íñigo Zubeldia, James Alvey et al. (+2 more)

The thermal Sunyaev–Zel'dovich (tSZ) power spectrum is a sensitive probe of cosmology and cluster astrophysics, but its statistics are non-Gaussian because the signal receives a significant contribution from rare, massive, low-redshift galaxy clusters. As a result, a Gaussian likelihood fails to describe the statistics of its power spectrum on large scales. We use simulation-based inference (SBI) to test the accuracy of the standard Gaussian power-spectrum likelihood for a Planck-like tSZ analysis. Using halo-based simulations of full-sky Compton-$y$ maps, we train neural posterior and likelihood estimators and compare the resulting constraints with those from a Gaussian likelihood assumption. Using only multipoles $\ell < 1000$, we find that the Gaussian likelihood assumption gives unbiased cosmological constraints, while the SBI-based inference shows a mild broadening of the posterior distributions for the amplitudes of residual foregrounds. This suggests that the Gaussian likelihood assumption is sufficiently accurate for cosmological inference for a Planck-like tSZ analysis, while SBI provides a useful validation tool to model non-Gaussian likelihoods beyond analytic approximations.
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All authors Licong Xu, Íñigo Zubeldia, James Alvey, Boris Bolliet, Anthony Challinor

Mathematical Physics

Tensor network manifolds and Riemannian fundamental theorem for tensor networks

Pablo Páez-Velasco

Tensor networks provide a powerful framework for efficiently representing high-dimensional data and many-body quantum states. Endowing tensor networks with a Riemannian manifold structure provides a natural setting for numerical optimization and analysis. A central feature of tensor networks is their gauge freedom, whose characterisation (captured by so-called fundamental theorems) underlies both their intrinsic structure and the design of numerical algorithms. In this work, we study the interaction between the Riemannian manifold structure and the gauge freedom for several families of tensor networks. Using group actions and Riemannian submersions, we establish a Riemannian fundamental theorem for the tensor network families studied.
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Optics

Scalable Fabrication of Thermally Reconfigurable Ge Metasurfaces Using Stencil Lithography for Mid-Infrared Molecular Sensing

Shovasis Kumar Biswas, Samir Rosas, Wihan Adi et al. (+4 more)

Mid-infrared (mid-IR) spectroscopy enables label-free molecular detection and is widely employed in biomedical, environmental, and chemical sensing; however, its broader deployment remains limited by bulky instrumentation and insufficient analytical sensitivity. Photonic metasurfaces supporting strong mid-IR resonances provide a promising route toward compact on-chip spectrometers and enhanced molecular sensing, yet their practical implementation is often constrained by limited spectral coverage and fabrication complexity. Here, we present a scalable, resist-free stencil lithography approach for fabricating arrays of Ge pillar metasurfaces on CaF2 substrates that support polarization-insensitive Mie resonances dominated by electric dipole modes. By varying the geometric design parameters during fabrication, we engineered metasurface arrays with discrete resonances spanning the 950-1700 cm^-1 molecular fingerprint region. Furthermore, leveraging the thermo-optic response of Ge, we achieved dynamic tuning of these discrete resonances, demonstrating continuous and reversible resonance shifts of approximately 36 cm^-1 per metasurface over 300-500 K, corresponding to a tuning rate of 0.18 cm^-1/K. The thermally induced spectral sweeping enables multiplexed detection of poly(methyl methacrylate) vibrational modes and continuous reconstruction of its absorbance spectrum across 1100-1215 cm^-1. These results establish a scalable dielectric metasurface platform with spectrally reconfigurable mid - IR modes for molecular sensing across the fingerprint region and compact infrared sensor technologies.
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All authors Shovasis Kumar Biswas, Samir Rosas, Wihan Adi, Aidana Beisenova, Vaishakh Unnikrishnan, Furkan Kuruoglu, Filiz Yesilkoy

Quantum Physics

On-site interactions in quantum thermal machines: efficiency, rectification and entanglement beyond local and global master equations

Salvatore Araceli, Teddy H. M. Ong, Baptiste Debecker et al. (+4 more)

Advances in experimental techniques have opened new routes for harnessing non-equilibrium dynamics in mesoscopic quantum systems. In this context, we study the impact of on-site interactions on the transport properties of a continuous quantum thermal machine composed of two coupled oscillators connected to two thermal reservoirs. In the weak system-reservoir coupling regime, where a long-standing debate concerns which reduced description should be preferred, we first show that the Redfield master equation (RME) provides an accurate and unifying framework that interpolates between two well-known limits: the local and global master equations. By relying on the Hierarchy of Pure States (HOPS), a numerically exact stochastic method, we then explore the full parameter space and show that interactions can be leveraged to tune the efficiency of the thermal machine at high temperatures (while leaving it essentially unchanged at low temperatures), induce non-reciprocal transport under asymmetric reservoir couplings, and generate steady-state entanglement within the junction. We derive expressions for system-bath correlators, such as heat and particle currents, consistently across different frameworks. Our work features on-site interactions to enhance the versatility of quantum thermodynamic junctions and clarifies the role of non-Markovianity and non-linearities in quantum transport.
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All authors Salvatore Araceli, Teddy H. M. Ong, Baptiste Debecker, Kai Müller, Oliver Lunt, Andrew J. Daley, François Damanet

Materials Science

Lattice dynamics and the spectroscopic signatures of H-bond disorder in $\delta$-AlOOH

Chenxing Luo, Sangjoon Lee, Hongjin Wang et al. (+2 more)

Raman and infrared anomalies associated with H-bond symmetrization in $\delta$-AlOOH, including mode softening and linewidth broadening at 5-10 GPa, occur at significantly lower pressures than predicted by static harmonic theory. To resolve this discrepancy, we combine harmonic phonon calculations with strongly constrained and appropriately normed (SCAN)-based deep-potential molecular dynamics and phonon quasiparticle analysis at 300 K. This framework extracts temperature- and pressure-dependent frequencies and lifetimes from long-time trajectories, capturing the branch reorganization and rapid linewidth growth characteristic of the disordering regime. Incorporating quasiparticle renormalization and directional longitudinal-optical-transverse-optical (LO-TO) splitting further yields near-quantitative agreement with the ambient-pressure OH-stretching Raman multiplet. These results identify finite-temperature dynamical effects and the progressive loss of spectral coherence as the origin of the spectroscopic signatures of H-bond symmetrization.
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All authors Chenxing Luo, Sangjoon Lee, Hongjin Wang, Zhen Zhang, Renata Wentzcovitch

Superconductivity

Tailoring the properties of YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ thin films by 30-keV He$^+$ irradiation: An enabling route to superconducting device nanopatterning

Bernd Aichner, Simon Koch, Philipp A. Korner et al. (+8 more)

Focused helium ion beam (He-FIB) irradiation with 30-keV ions is a key tool for nanoscale patterning and defect engineering in high transition temperature (Tc) cuprate superconducting devices, yet its usable fluence window is constrained by the competing requirements of reliable superconductivity suppression and minimal structural degradation. In this work, we provide a comprehensive dataset on the effects of large-area 30-keV He+ ion exposure on the electric transport and superconducting properties of epitaxial YBa2Cu3O7 (YBCO) thin films. X-ray diffraction shows a fluence-driven loss of crystalline order accompanied by an out-of-plane lattice expansion and an orthorhombic-to-tetragonal transition, culminating in predominant amorphization at the highest fluence of 1 x 10^16 cm^-2. Raman spectra exhibit increasing disorder while lacking signatures of oxygen depletion, indicating that irradiation mainly generates oxygen-related Frenkel defects rather than changing the carrier concentration. Consistently, with increasing fluence, the normal-state resistivity \rho_N(T) at temperature T above Tc increases strongly, while d \rho_N/d T remains nearly unchanged at moderate fluence. The suppression of Tc is accurately described by Abrikosov-Gor'kov pair breaking and reaches complete quenching of superconductivity at 4.5 x 10^15 cm^-2. The anisotropic upper critical fields decrease approximately exponentially with increasing fluence, the vortex activation energy is reduced, and the anisotropy drops, in contrast to oxygen-depleted YBCO. Hall-angle analysis confirms a nearly constant carrier density but a systematic increase in defect scattering and reduced mobility, consistent with a crossover toward the dirty limit at high fluence. These results establish quantitative fluence thresholds and a practical operational window for He-FIB nanopatterning of YBCO quantum circuits.
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All authors Bernd Aichner, Simon Koch, Philipp A. Korner, Max Karrer, Katja Wurster, Christoph Schmid, Ulrich Kentsch, Reinhold Kleiner, Edward Goldobin, Dieter Koelle, Wolfgang Lang

Fluid Dynamics

Wave turbulence theory of odd fluids and solids: kinetic equations and solutions

Xander M. de Wit, Léo Touzo, Sébastien Galtier et al. (+3 more)

The theory of wave turbulence describes the properties of physical systems composed of a set of weak-amplitude random waves interacting nonlinearly. Here, we study odd wave turbulence, which arises in chiral media subjected to non-reciprocal stresses, notably odd viscosity and odd elasticity. In both cases, we consider simple models for which we can derive and solve analytically the kinetic equations describing the long-term statistical behavior of spectral quantities such as energy or wave action. For odd viscosity, we consider a three-dimensional model that exhibits wave turbulence involving three-wave interactions, which gives rise to a direct energy cascade characterized by an anisotropic Kolmogorov-Zakharov (KZ) spectrum. For odd elasticity, we consider a quasi-one-dimensional overdamped model that exhibits much slower dynamics involving six-wave interactions. In that case, the KZ spectrum corresponding to a forward cascade of a conserved quantity we call odd energy, is nonlocal and therefore does not constitute a physical solution. However, the other KZ solution, which describes an inverse cascade of wave action, is only marginally non-local and is therefore valid up to a logarithmic correction. These two analytical theories provide a rigorous interpretation of direct numerical simulations, where the KZ spectrum is observed both in the case of odd viscosity (forward cascade) and of odd elasticity (inverse cascade).
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All authors Xander M. de Wit, Léo Touzo, Sébastien Galtier, Michel Fruchart, Federico Toschi, Vincenzo Vitelli