Lattice Field Theory
Future Requirements of Lattice Field Theory Calculations on European High-Performance Computing Facilities
Gert Aarts, Gunnar Bali, Jacob Finkenrath et al. (+4 more)
Lattice field theory provides a first-principles framework for studying properties of strongly interacting
quantum field theories in elementary particle physics. Researchers in
lattice field theory are also among the largest and most efficient users of high- performance computing resources in fundamental science. In this contribution, we outline the computational profile of
lattice QCD, from gauge-field generation to large-scale measurements, and discuss the main hardware, software, and human resource requirements needed to sustain progress on current and future European HPC infrastructures.
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All authors Gert Aarts, Gunnar Bali, Jacob Finkenrath, Stefan Krieg, Antonio Rago, Carsten Urbach, Hartmut Wittig
Applied Physics · Cross-listed from cs.AR
Mitigating the Impact of Retention Loss on Inference Accuracy in 65 nm Single-Poly Floating-Gate Analog In-Memory Computing
Mirko Brazzini, Giulio Filippeschi, Alessandro Catania et al. (+2 more)
We show with experiments and system-level simulations that it is possible to successfully mitigate the impact of retention loss on inference accuracy degradation by using both
circuit-level compensation techniques and batch normalization recalibration at the algorithmic level. Experiments are performed on a single-poly floating-gate (FG) analog non-volatile
memory array for analog in-
memory computing fabricated in a standard 65 nm CMOS. We use a model of retention-loss statistics calibrated with experiments to evaluate the system-level impact on neural network models such as VGG-10/CIFAR-10 and WideResNet-28-10/CIFAR-100. We show that, after 60 days since programming, combined mitigation techniques enable to recover the baseline inference accuracy within 2-4%
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All authors Mirko Brazzini, Giulio Filippeschi, Alessandro Catania, Sebastiano Strangio, Giuseppe Iannaccone
Solar and Stellar Astrophysics
Localized magnetic pressure anisotropy in strange dwarfs with crystalline crusts
Mila Leite Garcia Reis, Daniela Eller Uliana, Jaziel G. Coelho et al. (+1 more)
We study
equilibrium sequences of magnetized strange
dwarfs composed of a self bound MIT bag strange matter core, with \(B_{\rm bag}^{1/4}=145\,{\rm MeV}\), and an ordinary crystalline crust. The aim is to determine how
nuclear composition changes and
magnetic pressure anisotropy in the crust modify the mass radius relation. The strange core is kept isotropic, while the crust is described either by pure
nuclei stopped at the first inverse beta threshold or by electron capture sequences extended to
neutron drip for C, O, Ne, and Mg compositions; selected mixed crusts are also considered up to the first instability. The
stellar structure is solved with the radial pressure as the integrated pressure and with the anisotropic contribution \(2(P_t-P_r)/r\) restricted to the crust. This treatment is compared with ordinary white
dwarf sequences and with scalar pressure branch calculations. We find that extending the crust to
neutron drip produces more compact strange
dwarf branches than stopping at the inverse beta threshold, because the evolved crust is softer and the core crust transition occurs at higher pressure.
Magnetic anisotropy further shifts the selected branches toward smaller radii, with the effect visible across the compositions studied and clearer at fixed
stellar mass. The comparison with compact objects from the Montreal White
Dwarf Database is used only as an observational reference plane, but it indicates that compact white
dwarf candidates are a relevant region for testing small core strange
dwarf scenarios.
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All authors Mila Leite Garcia Reis, Daniela Eller Uliana, Jaziel G. Coelho, Edson Otoniel
High Energy Physics (Theory)
Junding Chen, Xi-Er Du, Hynek Paul et al. (+1 more)
We compute the leading
quantum gravity correction to the correlation function of two maximal
giant gravitons and two light supergravitons in the stress tensor multiplet in the supergravity limit of $\mathcal{N}=4$ SYM theory. By viewing the
giant gravitons as a zero-dimensional defect, we employ the defect version of the AdS unitarity method to reconstruct the one-loop correction from the known tree-level correlators. We obtain the one-loop result in closed form in both Mellin and position space. We also extract the
quantum correction to the anomalous dimension of operators describing a bound state of a
giant graviton and a light supergraviton at the leading conformal twist in the defect channel OPE.
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All authors Junding Chen, Xi-Er Du, Hynek Paul, Xinan Zhou
Astrophysics of Galaxies
Linking dynamics and chemistry in barred galaxies through action-space mapping
Tetsuro Asano, Victor P. Debattista and Michiko S. Fujii
We aim to extend the action-based framework, proposed by a previous study, for assigning chemical information to collisionless $N$-body simulations of barred
galaxies, enabling more realistic comparisons with observations. We developed a new method to map chemistry of
star-forming $N$-body+hydrodynamical simulations (donor models) onto pure $N$-body simulations (target models) using a matching
algorithm. We applied the method to two barred $N$-body
galaxies, one Milky Way (MW)-like with a classical bulge and another with a strongly buckled bar, combined with two
star-forming donor models exhibiting bimodal and unimodal chemical tracks in the [Fe/H]-[$\alpha/$Fe] plane. Our models reproduce key chemo-dynamical trends observed in the MW and external
galaxies. Metal-rich populations are more strongly associated with the X-shaped bulge morphology, leading to vertically pinched
metallicity maps consistent with observations and chemo-hydrodynamical simulations. The [Fe/H]-[O/Fe] distributions show latitude-dependent bimodality, and the mock magnitude distributions of red clump
stars reveal a stronger X-shape for metal-rich populations. In the model with a classical bulge, metal-poor
stars exhibit a more spherical morphology on the longitude-latitude plane, while metal-rich
stars show a boxy distribution, consistent with observations of the MW bulge. The proposed action-based chemical assignment provides a computationally efficient and flexible approach to link the dynamical and chemical
evolution of barred
galaxies. It enables realistic chemo-dynamical modelling of the
galactic bulges.
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Soft Condensed Matter
Transition between ground states in square anisotropic artificial colloidal ice
Leonardo G. Alanis-Cantú and Antonio Ortiz-Ambriz
In Artificial Colloidal Ice (ACI), paramagnetic colloidal particles are confined in double-well traps and interact via repulsive, isotropic,
magnetic dipole-dipole interactions that can be controlled by an external
magnetic field. In this paper, we dynamically introduce anisotropic interactions to ACI by rotating the external
magnetic field, which, in
equilibrium, makes the system go from a charge-free 2-in, 2-out ice rule state, to a charged 4-in, 4-out state. We observe a strong dependence of the final configuration on the field's rotation rate $\omega$: at high angular velocity, the system achieves a defect free final state via a difussionless transformation from the initial ground state. However, counterintuitively, at slow rotation rates, ergodicity breaks down, trapping the system in a partially ordered metastable state.
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Fluid Dynamics
Data-driven impeller model for efficient large eddy simulations of metastable von Kármán flows
Quentin Malé, Lucas Amoudruz, Daniel Bulgarini et al. (+5 more)
The von Kármán turbulent swirling flow exhibits intriguing large-scale metastable dynamics, including low-frequency state switching. The study of state switching demands long-duration high-fidelity simulations at high Reynolds numbers that capture the flow generated by the impellers. Blade-resolved Large Eddy Simulations (LES) are computationally prohibitive, limiting access to these slow dynamics. Here, we develop a model for the action of the impellers on the flow using experimental data from Particle Image Velocimetry (PIV) and torque measurements of the von Kármán flow. The impeller-region velocity is parametrized via B-splines and coupled to the LES through momentum forcing. An initial set of B-spline coefficients is inferred using the Optimizing a DIscrete Loss (ODIL) framework constrained by the Reynolds-Averaged Navier–Stokes (RANS) equations, PIV measurements in the optically accessible portion of the device, and impeller torque measurements. The coefficients are then refined by the Covariance
Matrix Adaptation
Evolution Strategy (CMA-ES), which minimizes the discrepancy between the LES time-averaged velocity and torque and their experimental counterparts. Using the data-driven impeller model, we perform long-duration LES of the von Kármán flow. We find that the simulation reproduces the mean flow in the bulk and displays metastable state-switching dynamics. We further show that these metastable states are not axisymmetric and consist of an alternating four-
cell flow pattern that slowly rotates around the axis of the cylindrical vessel. The proposed approach provides a practical and computationally efficient route to investigating large-scale dynamics in impeller-driven turbulent flows.
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All authors Quentin Malé, Lucas Amoudruz, Daniel Bulgarini, Shuolin Xiao, Gregory Eyink, Charles Meneveau, Fabrizio Bisetti, Petros Koumoutsakos
Astrophysics of Galaxies
A Deep Look at the Ultra-Faint Milky Way Satellite Virgo III with Rubin Observatory Data Preview 2
Aashay Pai, Alex Drlica-Wagner, Peter S. Ferguson et al. (+10 more)
We analyze the ultra-faint Milky Way satellite Virgo III using data from the Vera C. Rubin Observatory Data Preview 2 (DP2). Virgo III was observed in the Rubin "
Cosmic Treasure Chest" (M49) First Look field, which contains 924 visits in the u,g,r,i bands comprising ~10.5hrs of exposure time with LSSTCam. These data are considerably deeper than the majority of DP2, with a $5\sigma$ limiting magnitude that approaches the expected 10-year depth of LSST (~25.2-26.5mag, depending on band). We report the morphological and
stellar population parameters of Virgo III measured with the maximum-likelihood-based package ugali. The depth of the Rubin imaging yields more than a factor of four increase in the number of candidate member
stars ($N_* = 114^{+11}_{-11}$) relative to the Virgo III discovery results ($N_* = 25^{+5}_{-4}$), enabling significantly more precise morphological constraints. Our best-fit parameters broadly agree with previous measurements, further confirming that Virgo III has properties that are consistent with an ultra-faint
dwarf galaxy ($M_V = -2.72^{+0.49}_{-0.70}$; $r_{1/2} = 53^{+10}_{-8}$) located at a heliocentric distance of $D_\odot = 151^{+8}_{-8}$. We also demonstrate that the depth and photometric quality of the DP2 data are sufficient to separate metal-poor and metal-rich
stars in color-color space. We further present period estimates for the three known RR Lyrae member
stars derived from the DP2 forced photometry; we use theoretical Period-Luminosity-
Metallicity (PLZ) and Period-Wesenheit-
Metallicity (PWZ) relations to obtain independent distance estimates. We find that our period and distance estimates are broadly consistent with previous measurements for these RR Lyrae. These results demonstrate the power of LSST data for the discovery and characterization of ultra-faint
dwarf galaxies and motivate future searches for new satellites across the southern sky.
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All authors Aashay Pai, Alex Drlica-Wagner, Peter S. Ferguson, William Cerny, Chin Yi Tan, Jeffrey L. Carlin, Yumi Choi, Željko Ivezić, Andrés A. Plazas Malagón, Lauren A. MacArthur, Colin T. Slater, Dan S. Taranu, Brian Yanny
Materials Science
Citrine Informatics: Chemical & Materials Development Platform
Maxwell C. Venetos, Steven J. Brown, Kenneth Kroenlein et al. (+6 more)
Today the Citrine Platform regularly powers data-driven materials discovery across industries, having moved beyond one-off demonstrations into routine industrial practice. Getting there required solving a core set of recurring obstacles: experimental data are scarce, costly, and published in formats that resist reuse; conventional accuracy metrics overstate model performance under the extrapolative conditions that define discovery; and realistic design spaces are bounded by physics, manufacturability, supply, and cost. Developed over more than a decade as an integrated response to these obstacles, the Citrine Platform is organized as four cooperating stages within a closed sequential learning loop. Stage 1 ingests and featurizes data through the Graphical Expression of Materials Data (GEMD) model, which treats process history, measurement uncertainty, and provenance as first-class features. Stage 2 builds machine learning models with well-calibrated uncertainty, including multivariate prediction intervals for correlated objectives, and validates them with extrapolative cross-validation and dynamic discovery metrics rather than random held-out splits. Stage 3 encodes compositional, physical, processing, and economic constraints directly into the design space, and Stage 4 applies the FUELS sequential learning framework with uncertainty-aware acquisition functions to navigate large constrained spaces under tight evaluation budgets. Published case studies spanning organic
semiconductors, autonomous nanoparticle synthesis, and
benchmark optimization tasks demonstrate two- to nine-fold reductions in experimental effort relative to random search, illustrating a stack in which data, modeling, and design-space layers continuously co-evolve.
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All authors Maxwell C. Venetos, Steven J. Brown, Kenneth Kroenlein, Steven K. Kauwe, James E. Saal, Marco Musto, Matthew D. Gerboth, Kyle D. Miller, Gregory J. Mulholland
Astrophysics of Galaxies
How massive and clumpy must a quasar wind be to create emission line blueshifts?
James H. Matthews
Blue asymmetries (“Blueshifts”) in the C IV 1550A emission line are common in luminous
quasars. If they are formed in winds, how much energy, momentum and mass do those winds transport? We address this question by considering how much mass must be supplied through the line-forming region to maintain a given density and ionization state. Using a combination of 1D analytic and 2D numerical models, we find that for blueshifted C IV lines to form in a wind, the wind must have mass
outflow rates of $\sim 50 f_V$ times the
accretion rate, where $f_V \leq 1$ is the volume filling factor accounting for clumping. Our results therefore disfavour line formation in a smooth disc wind and point towards one of two scenarios: either the wind is clumpy, with required clumping factors suggestively close to those in hot
star winds; alternatively, if the mass is instead swept up from the ambient medium, the wind need not be clumpy and MHD and radiative winds can provide the original source of momentum and energy. The power of the
outflow depends on the square of the terminal velocity of the flow, $v_\infty$. If the wind is also the BAL
outflow, with $v_\infty \sim10,000~{\rm km~s}^{-1}$, the wind power is significant and important for feedback. There are various caveats which moderate our conclusions, motivating i) a better theoretical understanding of wind driving and clump formation physics and ii) improved observational constraints on the physical conditions where the lines are formed.
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High Energy Physics (Phenomenology)
Quantum detection of CP violation in the $t\bar{t}$ system: tomography
Priyanka Lamba, Fabio Maltoni, Olimpia Miniati et al. (+1 more)
We develop a
quantum-tomographic framework for determining whether possible CP-odd effects in $t\bar t$ events originate in production, in decay, or in both. In the narrow-width approximation, the process $I\to t\bar t\to b\ell^+\nu\,\bar b\ell^-\bar\nu$ factorises into a production density
matrix and top and antitop decay density
matrices. We extend the standard
tomography procedure to a general anomalous $Wtb$ vertex and derive the corresponding angular distributions. Polar-angle distributions retain their usual tomographic form, up to modifications of the
spin-analysing powers, and can therefore be used to reconstruct the production density
matrix and test its CP properties. By contrast, dedicated azimuthal observables involving the $b$–
lepton decay planes contain characteristic sine modulations that provide linear probes of possible new CP-violating interactions in the decay vertex. Combining the two classes of observables gives a systematic strategy for separating sources of CP violation in production and in decay. We illustrate the resulting angular signatures for representative $t\bar t$ production scenarios at
hadron and
lepton colliders.
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All authors Priyanka Lamba, Fabio Maltoni, Olimpia Miniati, Eleni Vryonidou
Nuclear Experiment
Laser Spectroscopy of Thulium Isotopes Near the $N=82$ Shell Closure: Nuclear Moment and Charge Radius of ${}^{152\mathrm{m}}\mathrm{Tm}$
Jana Weyrich, Kenneth van Beek, Harshithbabu et al. (+33 more)
We report on resonance ionization
laser spectroscopy measurements performed on both
neutron-deficient and
neutron-rich thulium ($\mathrm{Tm}, Z=69$) isotopes. Isotope shifts were determined for three atomic ground-state transitions at wavelengths of $389.8\,\mathrm{nm}$, $388.4\,\mathrm{nm}$, and $388.8\,\mathrm{nm}$ in the isotopes ${}^{152\mathrm{m}}\mathrm{Tm}$, ${}^{153}\mathrm{Tm}$, ${}^{154\mathrm{m}}\mathrm{Tm}$, and ${}^{169}\mathrm{Tm}$. In addition, for the $389.8\,\mathrm{nm}$ transition, measurements were extended to the isotope ${}^{170}\mathrm{Tm}$, and the hyperfine structure was partially resolved for all five isotopes. For this transition, the isotope shift could be determined for one more isotope, ${}^{154\mathrm{m}}\mathrm{Tm}$. From the extracted hyperfine coupling constants, the
nuclear magnetic dipole moment for ${}^{152\mathrm{m}}\mathrm{Tm}$ was determined for the first time, resulting in $\mu\left({}^{152\mathrm{m}}\mathrm{Tm}\right) = 5.8(3) \mu_\mathrm{N}$. Furthermore, the mean-square
nuclear charge radius $\delta\langle r^2\rangle^{152\mathrm{m},169} = -1.87(17)\,\mathrm{fm}^2$ for ${}^{152\mathrm{m}}\mathrm{Tm}$ was extracted from the measured isotope shifts.
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All authors Jana Weyrich, Kenneth van Beek, Harshithbabu, Aayush Arya, Sebastian Berndt, Michael Block, Alexandre Brizard, Premaditya Chhetri, Arno Claessens, Christoph Emanuel Düllmann, Rafael Ferrer, Sarina Geldhof, Francesca Giacoppo, Manuel J. Gutierrez, Raphael Hasse, Christian Helmel, Fritz Peter Heßberger, Julian Hindermann, Fedor Ivandikov, Biswajit Jana, Tom Kieck, Mustapha Laatiaoui, Nathalie Lecesne, Andrew Mistry, Danny Münzberg, Thorben Niemeyer, Sebastian Raeder, Elisabeth Rickert, Daniel Rodriguez, Herve Savajols, Matou Stemmler, Dominik Studer, Thomas Walther, Jessica Warbinek, Piet Van Duppen, Klaus Wendt
Statistical Mechanics
Phase Transitions and Order Parameters in Correlation Matrices: A Wishart-Ensemble Perspective on the Largest Eigenvalue
Roberto da Silva, Antonio Mihara, Henrique Tramontina et al. (+1 more)
We investigate the properties of the largest
eigenvalue of correlation
matrices within the framework of Wishart ensembles. In this work, we propose the largest
eigenvalue as an effective empirical order parameter for detecting phase transitions in chaotic and
spin systems, drawing an analogy between its derivatives and thermodynamic response functions derived from the free energy, however not necessarily linked to a critical divergence originally observed in the context of phase transitions theory.
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All authors Roberto da Silva, Antonio Mihara, Henrique Tramontina, Sandra D. Prado
High Energy Physics (Phenomenology)
Quantum detection of CP violation in the $t\bar{t}$ system: production
Priyanka Lamba, Fabio Maltoni, Olimpia Miniati et al. (+1 more)
We investigate how possible new CP-violating top-
quark interactions are encoded in the
quantum state of a produced $t\bar t$ pair. We derive analytic expressions for the production density
matrix in several
benchmark channels relevant to
hadron,
lepton and
photon colliders. In a common
spin basis, we identify two characteristic CP-odd structures in the Fano–Bloch decomposition: a difference between the top and antitop polarisation vectors and an antisymmetric component of the
spin-correlation
matrix. We construct observables that directly probe these structures and study how
quantum information measures, including discord, concurrence, magic and trace distance, respond to CP-even and CP-odd SMEFT contributions. Finally, using current measurements and future
collider projections, we assess the sensitivity of these observables to possible new sources of CP violation in top-
quark production. This establishes the production-level framework whose experimental reconstruction is developed in a companion paper.
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All authors Priyanka Lamba, Fabio Maltoni, Olimpia Miniati, Eleni Vryonidou
Physics and Society
Structural Analysis of Journal Columns Using Ordinal Patterns and Information-Theoretic Measures
Cynthia Z. Zhou-Lin, José L. Herrera-Diestra and Luciano Stucchi
Source attribution in journalistic text is typically approached through semantic representations, such as term weighting or neural
embeddings. These approaches capture topical content, but usually overlook how a text is organized as a sequence. Here, we show that purely structural, content-independent features can discriminate between news sources on their own. We converted articles from fourteen Peruvian online newspapers into numerical sequences using two independent encodings, word length and lexical frequency. Then, we analyzed each of them through ordinal pattern analysis, computing pattern and transition probabilities, permutation
entropy, disequilibrium, and statistical complexity. Both encodings yield non-uniform ordinal pattern distributions, well-defined preferential transitions, and coherent
entropy complexity signatures across sources. Unsupervised clustering recovers three coherent groups in the feature space, and supervised classifiers trained on these features achieve accuracy up to 0.99, which remains stable even under substantial feature reduction. The consistency of these results across two structurally unrelated encodings strongly indicates that ordinal features capture a genuine dynamical fingerprint of each source's writing style rather than an artifact of either representation, which extends this framework to Spanish-
language journalism, a setting that remains comparatively underexplored in complexity-based text analysis.
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Materials Science
Machine-Learning Potentials for sodium-potassium chloride mixtures: Predicting thermophysical properties and phase behavior of multicomponent salts
Karim Zongo, Hao Sun, Zijian Meng et al. (+3 more)
Predicting the properties of multicomponent molten salts using density functional theory (DFT) remains challenging because the spatial and temporal scales required to evaluate transport properties and phase behavior are computationally prohibitive. In this work, we develop a moment tensor potential trained using a a DFT
dataset of NaCl, KCl, NaCl-KCl mixtures, and the NaK
alloy, enabling large-scale molecular dynamics simulations across wide ranges of temperatures and compositions. We systematically evaluate the effect of D3 dispersion corrections and apply the resulting potential to predict
liquid densities,
diffusion coefficients, radial distribution functions, heat capacities, thermal conductivities, and the NaCl-KCl phase diagram. The model successfully reproduces many temperature- and composition-dependent trends. However, systematic deviations in several absolute properties persist, highlighting the importance of experimental validation and calibration. These findings support a hybrid modeling framework in which first-principles-informed machine-learning potentials provide transferable predictive capability and mechanistic insight, while experimental data incorporated during model development or subsequent engineering assessments is necessary to improve quantitative accuracy.
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All authors Karim Zongo, Hao Sun, Zijian Meng, Christopher Maxwell, Edmanuel Torres, Laurent Karim Béland
High Energy Physics (Phenomenology)
Few-gluon interactions and multipole radiation in high energy nuclear collisions
Thomas A. Trainor
Broad claims have been made over years about achievement of
quark-
gluon plasma (QGP) formation in high-energy heavy-ion collisions based on certain phenomena anticipated for QGP formation. More recently, similar phenomena have appeared in smaller collision systems. In response, the original narrative associated with QGP formation has been altered, with introduction of novel concepts such as “QGP droplets” appearing even in p-p collisions. In contrast, alternative research has revealed novel aspects of p-p and p-Pb collisions such as exclusivity for N-N interactions and consequences of time dilation for interacting partons. Collision geometry for A-B collisions has also been shifted from conventional Glauber Monte Carlo simulations (strongly biased) to inversion of ensemble-mean $\bar p_t$ data. The present study demonstrates that jet production dominates all aspects of $p_t$ spectrum structure and minimum-bias angular correlations over the full $p_t$ range of accessible data. Recently, progress has been made on interpretation of azimuth quadrupole ($v_2$) data, reexpressed in terms of total correlated-pair number as an extensive measure, leading to inference of quadrupole $m_t$ spectra and quadrupole amplitude variation across all A-B collision systems that show strong indication of the effects of exclusivity. The same approach applied to jet angular correlations shows similar trends. A comprehensive quantitative description of the two QCD phenomena across all collision systems has emerged. The underlying processes are few-
gluon interactions producing characteristic correlation structures corresponding to color-dipole (two-
gluon, dijet) and color-quadrupole (three-
gluon) radiation. That description does not rely on any role for a dense medium, multiple scattering, QGP droplets or hydro theory. It applies the same rules uniformly to small and large collision systems.
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High Energy Physics (Phenomenology)
Searches for heavy neutral lepton decays at spallation neutron sources
Valentina De Romeri, A. Galindo-Uribarri, Ana Martín-Galán et al. (+2 more)
Spallation
neutron sources provide intense
neutrino fluxes from pion and
muon decay at rest, with energies in the few tens of MeV range. Experiments such as COHERENT exploit these fluxes to detect
neutrinos via coherent elastic
neutrino$\unicode{x2013}$
nucleus scattering (CE$\nu$NS). However, these facilities also offer a unique opportunity to produce and probe light, secluded, or weakly$\unicode{x2013}$coupled particles. In this work, we investigate the sensitivity of the Spallation
Neutron Source at the Oak Ridge National Laboratory to heavy neutral
leptons (HNLs) in the MeV$\unicode{x2013}$GeV mass range, as a case study. We consider HNL production in pion and
muon decays at rest, followed by their decay into visible Standard Model particles within the detector volume. We analyze a range of current and proposed COHERENT detectors and evaluate their sensitivity to HNL mixing with
muon and electron
neutrinos, as well as to scenarios with mixed mixing. We find that existing detectors can set meaningful constraints, particularly for
muon$\unicode{x2013}$
flavor mixing, while future ton$\unicode{x2013}$scale realizations can probe previously unexplored regions of the parameter space. We further discuss prospects at other relevant spallation source facilities and comment on the complementarity of their projected sensitivities. Our results demonstrate that CE$\nu$NS experiments at spallation
neutron sources provide a powerful, complementary avenue for new physics searches beyond their primary role as
neutrino detectors.
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All authors Valentina De Romeri, A. Galindo-Uribarri, Ana Martín-Galán, Víctor Martín Lozano, G. Sanchez Garcia
Quantum Physics
Invariant-based master equation applied to driven qutrit coupled to a bath and a leaky cavity
Sagarika Basak, A. Javadi and D. Blume
We employ a generalized approach to the master equation for driven open $N$-level ($N>2$)
quantum systems using Lewis-Riesenfeld invariants, which avoids the driving-strength restrictions inherent to conventional approaches. We show that the invariant-based master equation provides a unifying generalized framework, which reduces to the frequently employed laboratory-frame master equations and the less frequently employed rotating-frame master equation framework under appropriate simplifications. Extending the prototypical two-level system, we show that the inclusion of another state coupled to the ground state via reservoir-induced dephasing gives rise to qualitatively new dissipative behaviors that are, in general, not captured by standard approximations. We also apply the invariant-based master equation framework to a driven
quantum dot coupled to a leaky cavity, demonstrating the framework's ability to capture relevant dissipative dynamics without additional assumptions. Our work paves the way for
quantum-control applications in the presence of dissipation.
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High Energy Physics (Phenomenology)
Regarding the Rotational Unruh Effect
A. Deur, S. J. Brodsky, C. D. Roberts et al. (+1 more)
We study the rotational Unruh effect by identifying the pseudodynamics which emerges when fundamental spacetime
symmetries are violated. We show that there is, fundamentally, no rotational Unruh effect, in agreement with the first explicit calculations of the literature, and that, when such an effect has been claimed to exist in later articles, its origin traces back to the derivation of the standard Unruh effect involving linear acceleration. Such a linear Unruh effect intrudes because the chosen reference frames do not respect the cylindrical
symmetry of the system, and thus the analyses require Lorentz boosts. Our study also confirms previous findings that the Unruh effect is a consequence of the pseudodynamics which arises because Instant-Form dynamics explicitly breaks a fundamental
symmetry of spacetime: Poincaré invariance.
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All authors A. Deur, S. J. Brodsky, C. D. Roberts, B. Terzić
Physics and Society
System optimality versus self-organization in metro networks: An optimal transport analysis
Tianyu Dong, Jiazu Zhou and Markus Schläpfer
Urban transportation network design is typically approached through top-down planning grounded in engineering and economics. Yet cities are complex systems characterized by feedback loops between infrastructure and mobility demand: network structure shapes origin-destination (OD) flows, while OD flows adapt and in turn affect network development. Despite this interdependence, computational tools to
benchmark real-world networks against alternative generative principles remain limited. Here, we introduce a data-driven framework to compare three types of metro networks: a self-organized (desire-path) network derived from local rules, a system-optimal network derived from global optimization, and the empirical real-world network. We quantify similarities and discrepancies using
geometric comparisons and optimal transport theory. Applying the framework to Singapore's Mass Rapid Transit system, we find that the empirical metro network is substantially closer to the self-organized
benchmark than to the system-optimal
benchmark, with remaining discrepancies largely explained by geographic constraints. These findings highlight that system-wide optimality alone may be inadequate for guiding practical interventions, motivating planning approaches that explicitly incorporate local service needs. The framework is transferable across regions and can diagnose design-use misalignments to support adaptive infrastructure planning.
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High Energy Physics (Phenomenology)
NNLO Determination of Polarized Parton Distribution Functions with Higher-Twist and Target-Mass Corrections
Javad Shahrzad, Elliot Leader and Ali Khorramian
We present a next-to-next-to-leading order (NNLO) QCD analysis of polarized parton distribution functions (PDFs) based on the world data set of inclusive polarized deep-inelastic scattering (DIS). The resulting PDF set, denoted as KLS26, includes a consistent treatment of target-mass corrections (TMCs), higher-twist (HT) contributions, and positivity constraints within a fully NNLO framework. To estimate the residual theoretical uncertainty associated with nonperturbative power corrections, both additive and multiplicative HT parametrizations are considered. Although these two approaches lead to different higher-twist coefficients, the current results yield very similar fit qualities and compatible polarized PDFs within uncertainties. The impact of NNLO corrections is assessed through a comparison with the KLSS21 polarized PDF determination at NLO, showing the most visible changes in the polarized strange-
quark distribution, together with moderate modifications in the
gluon sector and smaller effects in the up- and down-
quark helicity distributions. Additional fits treating the nonsinglet axial charges as free parameters, together with different higher-twist implementations, induce small but
flavor-dependent modifications in the PDFs, with the most noticeable effects in the polarized strange-
quark distribution and moderate sensitivity in the
gluon. The KLS26 set establishes an updated determination of helicity-dependent parton distributions, enabling future precision studies of nucleon
spin structure.
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Materials Science
MANDALA: An E(3)-Equivariant Graph Neural Network Framework for Learning Electronic-Structure Operators with Observable Guidance
Bartosz Brzoza, Wiktoria Szopa, Zakaria Elabid et al. (+5 more)
Electronic-structure calculations based on Kohn-Sham density functional theory remain indispensable in computational materials science and chemistry. Their computational cost, however, limits accessible system sizes and simulation times. At the same time, conventional machine-learning interatomic potentials (MLIPs), which are becoming the workhorse of large-scale materials modeling, usually target only energies and forces. They therefore leave out the
quantum-operator-level information required to reconstruct band structures, densities of states, spatial charge distributions, and other electronic observables. Mandala fills this methodological gap. It is a modular software framework for learning block-sparse electronic-structure
matrices with E(3)-equivariant graph neural networks. The framework is built around a unified representation of atom-resolved
Hamiltonian, overlap, and density
matrices, together with reusable abstractions for basis conversion, sparse block handling, irreducible representation mapping, graph construction, model definition, and training. This design allows Mandala to support heterogeneous chemical compositions, a wide range of neural architecture variants within one workflow, and multiple electronic-structure backends. Mandala evaluates selected observables directly from the predicted operators, including band energy, electron count, density of states, and band structure. This connects electronic-structure learning and observable-guided modeling while retaining a representation tied to
quantum-mechanical operators rather than only scalar or vector targets as in MLIPs. In this form, Mandala is intended to complement atomistic interatomic potential workflows by resolving electronic structure and operator-derived observables within one scalable implementation.
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All authors Bartosz Brzoza, Wiktoria Szopa, Zakaria Elabid, Vincent Martinetto, Varadarajan Rengaraj, Mani Lokamani, Thomas D. Kühne, Attila Cangi
Quantum Physics
A Model Predictive Control-Inspired Quantum Algorithm
Dominic Messina, Alicia B. Magann, Mohan Sarovar et al. (+1 more)
We introduce a new hybrid
quantum-classical
algorithm inspired by an advanced control strategy known as model predictive control (MPC). This
algorithm unifies the optimization-based design of variational
quantum algorithms (VQAs) with the feedback-based design of feedback-based
quantum algorithms (FQAs). Variational
circuit parameters are optimized using a layer-wise receding horizon strategy, where observable measurements after every layer initialize a classically simulated dynamic model used to predict
quantum state
evolution and optimize over future parameterized gates. This hybrid
algorithm can be used for applications such as ground state preparation and approximate combinatorial optimization, and presents an ideal use case for the integration of
quantum computers with high-performance computing, where the latter resource can be used to increase the scale and efficiency of the predictions critical to MPC. We show through mathematical proof and numerical evidence that the MPC-based
algorithm can be guaranteed to at least match the performance of FQAs. Through simulations on Max-Cut problems and a two-dimensional transverse-field Ising model, we demonstrate that relaxed implementations of the MPC-based
algorithm can also provide improved performance in practice compared to an FQA.
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All authors Dominic Messina, Alicia B. Magann, Mohan Sarovar, Helen Durand
High Energy Physics (Theory)
Cross-Correlations of Metric and Monopole Perturbations from Holographic Cosmology
Matheus Cravo, Juliana Z. Finotti and Horatiu Nastase
In this paper, we present the 1-loop calculation of the three-point function $\langle TJJ \rangle$ of the stress-energy tensor and two insertions of $SO(3)$ global currents, using a 3d toy model for
holographic cosmology. By applying the
holographic dictionary that relates these QFT $n$-point functions to cosmological correlators, together with the $Sl(2,\mathbb{Z})$ duality that maps the electric Noether current to a
magnetic vortex current dual to cosmological
magnetic monopoles, we relate the $\langle TJJ \rangle$ correlator to the cross-correlations between metric perturbations and the bulk
magnetic monopole field, specifically mapping to the non-Gaussianities $\langle \xi \tilde{A} \tilde{A} \rangle$ and $\langle \gamma \tilde{A} \tilde{A} \rangle$. We calculate the semi-local contact terms necessary to achieve the exact factorization of the cosmological correlators in the squeezed limit, $p_1 \to 0$. Finally, we evaluate the effective non-linear parameters, showing that the scalar-monopole cross-correlation vanishes at leading order, $f_{NL}^{\xi \tilde{A} \tilde{A}} = 0$, while the tensor-monopole cross-correlation yields a non-zero $f_{NL}^{\gamma\tilde A\tilde A}$. These results respect the expected amplitude hierarchy of the non-Gaussian correlators, while pointing at new directions in which
holographic cosmology can be tested experimentally.
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Quantum Physics
Maximal complementarity in the n-qubit Pauli group
Markus Frembs, Giovanni Natale, Christopher S.P. Wever et al. (+1 more)
Observables in
quantum mechanics are generally complementary, that is, they reveal mutually incompatible pieces of information about a given system. This property is not only a fundamental tenet of the
quantum formalism, but also a key component in
quantum cryptographic protocols. As such it has fuelled much research into finding sets of highly complementary observables. In its strongest form – the one we consider in this work – the information between complementary observables is not merely incompatible but mutually exclusive: maximal information about one observable implies no information about the other, and vice versa. Maximal sets of non-degenerate complementary observables are known to exist in systems of
prime power dimension such as n-
qubit systems. Here, we study complementarity of degenerate observables, specifically we prove that observables associated with the n-
qubit Pauli group also exhibit complementarity under this restriction: first, we obtain a criterion for two such observables to be complementary and, second, we relate maximal sets of complementary observables with informational pure state complementarity equalities, further studied in two companion papers. Equivalently, these results can be formulated in terms of maximal complementary sets of (not necessarily maximal) Abelian subgroups of the Pauli group linking with (possibly coarse-grained) mutually unbiased bases. Finally, we prove that these complementarity sets entail strong entropic uncertainty relations.
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All authors Markus Frembs, Giovanni Natale, Christopher S.P. Wever, Philipp A. Hoehn
Quantum Physics
An algebraically closed family of informational n-qubit purity invariants
Markus Frembs, Giovanni Natale, Christopher S.P. Wever et al. (+1 more)
We present a family of quadratics in Pauli expectation values, and prove that they constitute state-independent invariants for all n-
qubit pure states. This family generalises the two-
qubit `pentagon identities', discovered in the reconstruction programme of [P. A. Höhn,
Quantum 1, 38 (2017), P. A. Höhn and C. S. P. Wever, Phys. Rev. A 95, 012102 (2017)], where they characterise the space of pure states, as well as the
unitary group, and are interpreted as complementarity equalities in the Brukner-Zeilinger information measure. The generalisation to arbitrarily many
qubits is nontrivial as it requires new tools which in turn reveal novel structural properties that are absent in the two-
qubit case. A thorough analysis of these properties, and their relation with mutual unbiasedness and complementarity in the n-
qubit Pauli group, can be found in two companion papers.
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All authors Markus Frembs, Giovanni Natale, Christopher S.P. Wever, Philipp A. Hoehn
Optics
A generalized Kirchhoff's law of thermal radiation for Floquet media
Sander A. Mann, Dimitrios L. Sounas and Andrea Alù
Kirchhoff's law fundamentally relates thermal emission to absorption. For linear, static, reciprocal media, it equates the emissivity and absorptivity for each direction and frequency, while in nonreciprocal systems emission and absorption are equal when the bias is time-reversed. In time-varying media, however, temporal modulation breaks time-translation invariance, converts frequencies, and enables energy exchange with the modulation drive. As a result, a same-frequency relation between absorptivity and emissivity can no longer be expected. Here, we derive a generalized Kirchhoff's law for linear time-varying Floquet media. We show that the emissivity at a given frequency equals a weighted sum of harmonic-resolved absorptivities of the adjoint system, with weights accounting for thermal occupation and
photon-flux conversion. This relation has both practical and fundamental consequences. In practical terms, it allows emissivity to be calculated from absorption, simplifying the design of time-varying thermal emitters. More fundamentally, it reveals thermal radiation regimes inaccessible in static media. In particular, we identify time-varying structures that exhibit strong emission with negligible absorption at the same frequency for all directions, yielding a near-maximal violation of the conventional form of Kirchhoff's law.
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Geophysics
Automatic Knowledge Graph Construction and Query for Earthquake Catalogs
Yuxin Zhou, Huai Zhang and S. Mostafa Mousavi
In recent years, the number of events in earthquake catalogs has significantly increased due to the utilization of more effective deep learning based detectors and phase pickers but answering open ended questions such as what characterizes this sequence? remains constrained by rigid spatiotemporal windowing and subjective expert interpretation. We present the first systematic application of graph based
retrieval augmented generation GraphRAG directly to raw, tabular catalog records across three independently featured catalogs, a reservoir adjacent swarm, the 2019 Ridgecrest tectonic sequence, and the 2021 Maduo Mw7.4 aftershock sequence. Without the need for manual data structuring, the pipeline builds structurally complete, queryable knowledge graphs for all three. Rigorous evaluation individually verified against catalog derived ground truth and a rule based reference graph exposes failure modes, and four seismology informed
prompt fixes eliminate all targeted fabrications while sharply improving mechanism
reasoning. A vector RAG baseline demonstrates the graph layers distinctive value, catalog wide summarization and temporal stage comparison. In addition, we have identified two main pitfalls that need
attention. GraphRAG thus offers a practical, transferable, near zero cost query interface for earthquake catalogs, where careful prompting ensures the results are consistently accurate and trustworthy.
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General Relativity and Quantum Cosmology
Coupled Gravitoelectromagnetic Response of a Magnetically Supported Generalized Hayward Black Hole in Nonlinear Electrodynamics
Anirudh Pradhan, K. Ghaderi, M. Zeyauddin et al. (+1 more)
We construct the exterior coupled gravitational and electromagnetic response of a magnetically supported generalized Hayward black hole within a specified nonlinear electrodynamic completion. Both parity sectors reduce to canonical two channel wave systems with explicit potentials and the correct Schwarzschild and effective Reissner–Nordström limits. We compute the quasinormal spectrum, metric and optical characteristics, extremal throat weights, quadrupolar wave conversion, finite bandwidth transfer, and coherent absorption eigenchannels while verifying exterior hyperbolicity and flux conservation. An effective charged operator captures the leading weak core geometry and mode mixing; after its subtraction, the residual hierarchy is consistent with cubic spectral corrections in the primarily electromagnetic branch and quartic corrections in the primarily gravitational branch and principal scattering observables. The fundamental quadrupolar branches become intrinsically linewidth separated near $\chi\simeq0.70$, whereas parity splitting remains subleading. Metric and optical characteristic families separate monotonically toward extremality. At $\chi=0.9$, positive parity reflected conversion reaches $45.8\%$ and remains $40.8\%$ after moderate bandwidth averaging, while coherent incident combinations yield $98.4\%$ bright and $1.3\%$ dark absorption. These independently evaluated observables provide mutually consistent diagnostics of the same nonlinear electrodynamic operator.
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All authors Anirudh Pradhan, K. Ghaderi, M. Zeyauddin, A. Gulhane