Strongly Correlated Electrons
Shovan Dan, Suman Nandi, Gourav Dwari et al. (+5 more)
We report a detailed anisotropic studies on the
magnetic and transport properties of a CeRu$_2$Ge$_2$ single
crystal. A clear
ferromagnetic transition is observed at $T_{\rm C} = 7.5$~K in the
magnetic susceptibility, electrical resistivity and heat capacity measurements. The magnetoresistance (MR) is positive at low temperature within the magnetically ordered state. We confirmed the presence of a
magnon excitation gap in the resistivity, MR and the low temperature heat capacity data. The pronounced anisotropy observed in the
magnetic susceptibility and magnetization along the [100] and [001] directions is quantitatively explained within the
crystal electric field (CEF) framework using the point-charge model. The analysis reveals a CEF level scheme comprising three doublets, with a ground state and two excited states at 491 and 671~K, that was further confirmed from the Schottky effect in the
magnetic part of the heat capacity data. Unlike most Kondo
lattice ferromagnets of Ce compounds, where the
magnetic easy axis deviates from the expected CEF ground state, CeRu$_2$Ge$_2$ exhibits magnetization, which is fully consistent with the CEF derived ground state wave function, with the easy axis of magnetization aligned along the [001] direction.
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All authors Shovan Dan, Suman Nandi, Gourav Dwari, Bishal Baran Maity, Bhagyashree A Chalke, Ruta Kulkarni, P. D. Babu, Arumugam Thamizhavel
Disordered Systems and Neural Networks
Topological phase transition driven by structural defects
Andrii Syrota, Andrej Mesaros and Pascal Simon
Structural defects, such as disclinations and dislocations, destroy the long-range crystalline order as they proliferate. In this work, we continuously drive a system from a crystalline state on a decorated honeycomb
lattice to a hyperuniform amorphous state, by consecutively introducing Stone-Wales (SW) defects, which can be viewed as dipoles of dislocations. Using a topological Weaire-Thorpe
Hamiltonian model to describe electrons in this system, we demonstrate that SW defects can cause pseudo-band inversions and, correspondingly, a reversal of the Chern number. Using adiabatic arguments and a computationally efficient spillage indicator, we predict the topological phase diagram of the amorphous state from the crystalline one. We explain the nature of the pseudo-band inversion through the renormalization of the hopping in an effective
Hamiltonian based on a single SW defect.
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Quantum Physics
Preselection-Encoded Weak-Value Interferometry for Optical-Rotation Metrology
Jinyi Li, Juncheng Zheng, Yuntao Shen et al. (+5 more)
Optical-rotation measurements benefit from increasing probe
photon number, but their performance is often limited by detector saturation and technical noise in the optical readout. Here we introduce preselection-encoded weak-value amplification (PeWVA), in which the quantity of interest is encoded into the probe polarization before a downstream weak-value interferometer. This architecture separates the sensing interaction from the postselected readout, enabling tunable local amplification while reducing the optical power delivered to the detector. We show that PeWVA does not create additional Fisher information, but offers a practical advantage when detector dynamic range is limiting. We further analyze coherent stray light and phase fluctuations and show reduced conversion of these perturbations into equivalent rotation errors. Using an $^{87}$Rb $M_x$ atomic magnetometer, we experimentally demonstrate substantially improved
magnetic-field readout under detector-constrained conditions using both transimpedance-amplified and avalanche photodiodes. The experiments also confirm reduced susceptibility to vapor-
cell-induced stray light and interferometer phase modulation. These results establish PeWVA as a detector-constrained optical readout strategy with enhanced tolerance to representative interferometric perturbations.
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All authors Jinyi Li, Juncheng Zheng, Yuntao Shen, Jiashu Liang, Sicheng Pan, Dongmei Li, Hengyan Wang, Wenqiang Zheng
Materials Science
Microstructure, tensile behavior and cyclic bendability of directly extruded biodegradable Zn, Zn-Mg and Zn-Mg-Sr wires
L. Hlodák, K. Tesař, M. Lebeda et al. (+5 more)
Zinc-based
alloys are promising biodegradable implants, yet the trade-off between strength, ductility, and bendability in thin-wire form remains poorly understood. To address this, pure Zn (PZ), Zn-0.15Mg (ZM), and Zn-0.8Mg-0.2Sr (ZMS) wires of ~290 um diameter were produced by direct extrusion, and their microstructure, texture, tensile, and bending behavior were characterized. Mg2Zn11 and SrZn13 phases promoted particle-stimulated nucleation, refining the grain size from 35.8 um in PZ to 6.8 and 3.3 um in ZM and ZMS, respectively, weakening the basal-fiber texture, and raising the ultimate tensile strength at 37 {\deg}C from about 119 MPa for PZ to 291 and 334 MPa for ZM and ZMS, respectively. PZ deformed through twin transmission across weakly misoriented grains, producing serrated stress drops in tensile curves, with further straining accommodated by non-basal slip. ZM showed a single, aging-sensitive stress drop from localized twin nucleation and particle cracking, while ZMS showed distributed particle cracking without associated stress drops, consistent with its higher elongation to failure of 19 % at 37 {\deg}C. Mechanical properties remained broadly stable after 20 days of aging at 37 {\deg}C, with no measurable change in the nanoscale precipitates after 7 days. All compositions, however, showed markedly poor cyclic bendability accompanied by a twinning-detwinning mechanism directly observed by EBSD for the first time in zinc. These results establish single-step direct extrusion as a viable route to strong, fine-grained biodegradable Zn wires, while identifying poor bendability as the principal obstacle to bending-critical biomedical devices.
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All authors L. Hlodák, K. Tesař, M. Lebeda, J. Duchoň, J. Kubásek, J. Čech, A. Školáková, J. Pinc
Earth and Planetary Astrophysics
High-resolution optical spectroscopy reveals the distinctive volatile composition of the interstellar comet 3I/ATLAS
K. Aravind, E. Jehin, C. Opitom et al. (+9 more)
Comets preserve volatile material from the early stages of planetary-system formation. The discovery of the interstellar comet 3I/ATLAS enables a direct comparison between a comet formed around another
star and comets in the
Solar System. We characterise the coma composition of 3I/ATLAS across perihelion using homogeneous high-resolution near-UV and optical spectroscopy with UVES on the ESO Very Large
Telescope, from August 2025 (r$_h$=3.14 au) pre-perihelion to February 2026 (r$_h$=4.34 au) post-perihelion. From flux-calibrated spectra, we measured OH, NH, CN, C$_3$, CH and C$_2$ emissions, derived production rates, examined abundance ratios and heliocentric-distance trends, constrained NH$_2$, and compared OH-based water production with estimates from forbidden oxygen lines. Gas production rates show broadly symmetric pre- and post-perihelion behaviour, with steeper heliocentric-distance dependences than typically observed in
Solar System comets. NH and NH$_2$ are strongly depleted, indicating a severe deficiency of ammonia-related volatiles. The C$_2$/CN ratio indicates carbon-chain depletion and evolves with heliocentric distance, consistent with coma-driven effects such as hyperactivity rather than intrinsic compositional changes. Water production from forbidden oxygen lines exceeds OH-based estimates except near perihelion, suggesting varying contributions from H$_2$O and CO$_2$ to coma chemistry. Relative abundance correlations place 3I/ATLAS outside the canonical
Solar System comet cluster and closest to strongly carbon-chain depleted comets, including G-Z-type comets, while showing strong depletion of NH- and C$_3$-bearing species relative to CN. 3I/ATLAS therefore extends the known diversity of cometary compositions, demonstrating that volatile reservoirs in other planetary systems can differ substantially from those sampled by
Solar System comets.
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All authors K. Aravind, E. Jehin, C. Opitom, J. Manfroid, D. Hutsemékers, D. Bodewits, M. Bannister, R. C. Dorsey, L. Ferellec, H. Kawakita, M. Lippi, C. Snodgrass
General Relativity and Quantum Cosmology
Radial quantization of the Schwarzschild geometry: relational observables, evaporation, and remnant state
David Brizuela, Leonardo Chataignier and Mikel López-Escondrillas
We consider the canonical quantization of the Schwarzschild geometry in a minisuperspace description based on a foliation with leaves labeled by the radial variable. This formulation remains regular across the Killing horizon. In this way, the resulting
quantum theory admits a physical
Hilbert space of states that solve the radial constraint equation and simultaneously describe the exterior and interior regions of the black hole. We discuss the construction of
quantum relational observables, which act as gauge-invariant symmetric operators on the physical
Hilbert space. In order to analyze
quantum effects on the geometry, we construct a family of semiclassical intelligent states that saturate the Robertson-Schrödinger uncertainty relation for both the black-hole mass and the asymptotic Killing norm, while exhibiting small relative fluctuations. The expectation values of relational observables in these states admit a clear
geometric interpretation, and they lead to an effective,
quantum-corrected spacetime. In particular, we find that the position of the horizon may be shifted, depending on the correlation of the state. In addition, both the proper acceleration of a static observer and the horizon surface
gravity are enhanced with respect to a classical Schwarzschild black hole with the same horizon area. Using the relation between surface
gravity and temperature, we then obtain corrections to the thermodynamic properties of the black hole, leading to a logarithmically corrected Bekenstein-Hawking
entropy. Finally, we discuss the definition of a state of minimal energy that could be interpreted as a stable remnant characterized by a finite horizon radius, suggesting a possible mechanism for preventing the complete evaporation of the black hole.
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High Energy Astrophysical Phenomena
Self-consistent modeling of energy-dependent synchrotron polarization in blazars with application to Mrk 421
Frederike Apel, Motseothata Tisang, Victor Barbosa Martins et al. (+3 more)
Observations of black hole jets closely aligned with our line of sight, known as blazars, have revealed that their X-ray emission can be significantly more polarized than in the optical bands. This chromatic polarization is often attributed to an energy-stratified jet. In blazars with X-ray emission dominated by electron synchrotron, the pitch angle between the
magnetic field lines and electron velocity might also affect the frequency dependence of the polarization degree, but this effect is generally neglected in state-of-the-art models. In this work, we model the polarization and spectral energy distribution of blazars, accounting for the system's temporal
evolution and pitch-angle-dependent electron synchrotron cooling. Our analysis investigates the impact of the
magnetic field structure and electron distribution on polarization and tests whether this can help explain its observed frequency dependence. By extending the numerical simulation code AM3, we incorporate a self-consistent calculation of electron synchrotron emission and simulate various
magnetic-field structures. We apply these models to Mrk 421 and compare them with observations. Finally, we present a time-dependent shock-in-jet model to investigate frequency-dependent polarization angle swings. Our results show how different
magnetic-field structures affect energy-dependent polarization signatures. In the case of Mrk 421, the data can be explained by a helical field in the jet. In the shock-in-jet scenario, the X-ray polarization angle changes by 70 degrees, while remaining almost constant in the optical/infrared. Our results demonstrate that a self-consistent treatment of the temporal
evolution of electrons is essential to model the polarized synchrotron emission from blazars and can naturally explain chromatic polarization signatures without requiring an energy-stratified jet.
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All authors Frederike Apel, Motseothata Tisang, Victor Barbosa Martins, Xavier Rodrigues, Markus Böttcher, Anna Franckowiak
Quantum Physics
Power-resolved ergotropy and correlation redistribution in a bosonic quantum battery driven by a coherent-state superposition
João P. d'El-Rey, Tailan S. Sarubi, Ana C. S. Costa et al. (+1 more)
Ergotropic-gap relations provide thermodynamic witnesses of
quantum correlations, but a direct dynamical connection between extractable work and
entanglement remains largely unexplored in multipartite non-Gaussian bosonic systems. Here, we establish such a connection for a bosonic
quantum battery driven by a coherent-state superposition. Despite the infinite-dimensional
Hilbert space, the dynamics retains a simple structure that allows the relevant work and correlation measures to be obtained exactly. We show that the loss of extractable work associated with the passive part of the battery energy is directly determined by charger-battery
entanglement. This relation also separates the charging power into contributions from energy transfer and from changes in the battery spectrum. At the same time, multipartite correlations are progressively redistributed from charger-involving correlations to correlations internal to the battery. For a symmetric resonant protocol, complete energy transfer coincides with charger-battery disentanglement and fully extractable stored energy, while multipartite correlations within the battery are maximal. Individual
cells, however, remain mixed, revealing a distinction between global and local work extraction. We further show that, in the regime considered, locally extractable work is entirely supported by energetic coherence. Under single-
photon loss, the analytical structure survives, but environmental correlations separate charger disentanglement from maximal work extraction.
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All authors João P. d'El-Rey, Tailan S. Sarubi, Ana C. S. Costa, José G. G. de Oliveira Jr
High Energy Physics (Theory)
BRST quantization of the induced gauge theory for the Higgs-branch CFT${}_2$
Bogdan Stefański Jr
We study Witten's induced gauge theory associated with the D1-D5
Higgs-branch CFT${}_2$, in which the non-dynamical vector multiplet becomes reanimated by integrating out the fundamental hypermultiplets. We propose a BRST quantisation of this theory and derive its induced propagators. We show that the ghost sector first contributes at subleading order, that the induced $A\phi^2$ vertex satisfies the Slavnov-Taylor identity and that gauge-invariant correlators are independent of the gauge parameter. Together with our chosen regularization prescription, this gives a perturbative framework for computing observables in the induced theory.
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High Energy Physics (Phenomenology)
A Simple Dark Matter Model to Explain the LZ Event and Galactic Center Excess
Caleb Gemmell, Dan Hooper and Gordan Krnjaic
We propose that the dark matter (DM) is a pseudo-Dirac
fermion with a mass of approximately $20-100$ GeV that couples inelastically to the Standard Model through a hadrophilic
spin-1 mediator, $V$, the gauge
boson of spontaneously broken
baryon number. The two DM eigenstates, $\chi_{1}$ and $\chi_2$, acquire approximately equal abundances after thermal freeze-out and are depleted through the processes $\chi_1 \chi_1 \to VV$ and $\chi_2 \chi_2 \to VV$. Although the heavier state is unstable, for a mass splitting below the electron-positron threshold and sufficiently small mass mixing with the $Z$
boson, its lifetime can exceed the age of the universe, allowing both states to remain approximately equally abundant in the
Galactic halo. For a thermal-relic annihilation cross section, this model can produce a signal that is consistent with the observed features of the longstanding
Galactic Center Gamma-Ray Excess (GCE). If $\delta \sim 1000$ keV, the same parameter space that explains the GCE can also explain the LZ event through exothermic $\chi_2 \to \chi_1$ downscattering off xenon
nuclei.
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Physics and Society
A Dynamic Model of Party Differentiation under Electoral Competition
Junjie Liu and Wencheng Lin
Why do political parties polarise when most voters remain in the centre? Moving beyond conventional point-based models, we address this classic puzzle by developing a spatial voting framework that conceptualises political parties as continuous ideological distributions. Operating under endogenous turnout, these parties adapt their positioning to maximise a combination of total votes and parliamentary representation. We demonstrate that this theoretical formulation reveals a distinct phase transition in multiparty competition, moving from centripetal convergence to centrifugal separation. These dual objectives do not necessarily reward the same directional party movement as voters only cast ballots for ideologically acceptable parties. The numerical results map the precise boundaries of this transition: a higher party count destabilises the centrist
equilibrium and expands the zone of divergence, whereas pronounced internal party dispersion and a stronger emphasis on representation contract it. Furthermore, electoral institutions critically govern this divergence: when voter preferences vary across geographic districts, the same national electorate can trigger entirely different phase transitions depending on how votes are converted into seats. Together, our results show how party differentiation emerges endogenously from the dynamics of electoral competition itself. Whether small initial differences grow or decay is not merely a reflection of voter preferences, but an outcome dictated by party goals, competitor count, internal party breadth, and vote-to-seat conversion rules.
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General Relativity and Quantum Cosmology
Regular Cosmologies: Three Distinct Routes
Sergio Bravo Medina and Marek Nowakowski
Regular black holes avoid the central singularity by replacing it with a de Sitter core. We ask what cosmology follows if the same idea is brought to the early universe. Regular metrics define a position-dependent cosmological term, $\Lambda_{\rm eff}(r)=8\pi G \rho_{\rm MS}(r)$, and there is no unique way to carry it over to the expanding universe. We follow three different prescriptions: a Newtonian one following McCrea and Milne, a running
vacuum evaluated at Hubble radius and a quasi-local one based on Misner-Sharp mass. We apply each of them to six regular black hole metrics and explore their consequences. In the Newtonian case the Friedmann equations are solved in closed form for the Hayward metric, and in terms of standard special functions or numerically for the others, and describe a universe that starts in a de Sitter phase and ends as
dust (i.e. an inflationary model instead of dark energy). We find that in all three prescriptions a monotonically decreasing core density gives an equation of state that never crosses $w=-1$, and thus the phantom behaviour suggested by DESI would require a density shell which a regular core does not have. The three prescriptions agree on the de Sitter core but differ at late times, and we quantify the difference against the DESI DR2 results. We also point out that a single regularisation length cannot serve as both the inflationary and the dark-energy scale.
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Materials Science
Superfluorescence as a cooperative amplifier of hidden anisotropy in a ferroelectric hybrid perovskite
Changhao Gao, Daniel Sandner, Talia Ruhrberg Estévez et al. (+4 more)
Superfluorescence (SF), intense picosecond bursts from self-synchronizing dipoles, is promising for room-temperature
quantum sources. Yet, whether this synchronization can convert weak structural anisotropies into robust macroscopic order remains an open question. Here, we demonstrate that polycrystalline ferroelectric 2D perovskite thin films exhibit strongly linearly polarized SF with a degree of polarization (DOP) up to 86%. Remarkably, macroscopic polarization emerges without external bias despite randomly oriented microscopic domains, suggesting a cooperative gain mechanism that amplifies weak local anisotropies by several orders of magnitude into coherent, linearly polarized light bursts. Our results establish cooperative superfluorescence as a general concept for translating microscopic anisotropy into robust macroscopic order, exemplified here for linear polarization, offering a sensitive probe of hidden material
symmetries and a framework for polarized
quantum light sources
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All authors Changhao Gao, Daniel Sandner, Talia Ruhrberg Estévez, Jeron Timmer, Sophia Klubertz, Martijn Kemerink, Felix Deschler
Cosmology and Nongalactic Astrophysics
Constraining Inflation with Little Red Dots
Dionysios Karagiannis and P. Daniel Meerburg
Primordial non-Gaussianity is a direct probe of the physics of inflation. The tightest bounds still come from the
cosmic microwave background, but large-scale structure is rapidly catching up: its intrinsically three-dimensional maps contain far more modes, provided the tracer combines large volume, high
redshift, strong bias and sufficient number density. The Little Red Dots (LRDs) discovered by JWST plausibly offer all four. Inspired by recent work on BAO measurements using LRDs we forecast the joint
galaxy power spectrum and bispectrum of a $14{,}000\,{\rm deg}^2$ LRD spectroscopic survey over $4<z<9$, marginalising over $32$ nuisance parameters and including the non-Gaussian bispectrum covariance. We find $\sigma(f_{\mathrm{NL}}^{\mathrm{loc}})=0.32$, $\sigma(f_{\mathrm{NL}}^{\mathrm{equil}})=32$ and $\sigma(f_{\mathrm{NL}}^{\mathrm{orth}})=10$, improving on Planck by factors of $16$, $1.5$ and $2.3$. The local bound lies a factor of three below the $\sigma(f_{\mathrm{NL}}^{\mathrm{loc}})\simeq1$ threshold that separates broad classes of single- and multi-field inflation. LRD clustering therefore has the potential to become an important probe of inflation, and makes a strong case for future wide-field near- to mid-infrared spectroscopy.
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Quantum Physics
Magnetic tuning of quantum backflow: Schrödinger vs Pauli system
Tomasz Radozycki
Probability backflow is investigated for charged
spin-$1/2$ particles in a uniform
magnetic field within the lowest-Landau-level approximation. While single-mode Landau states exhibit only weak and non-robust backflow, it is shown that two-mode interference gives rise to negative probability flux in both the Schrödinger and Pauli formulations. In the Pauli case, orbital and
spin contributions to the probability current are explicitly separated, revealing an additional interference mechanism. The external
magnetic field is found to act as a tunable control parameter, simultaneously controlling the spatial overlap of orbitals and the
spin dynamics. In the two-mode regime, a resonance between orbital mismatch and
spin precession leads to an enhancement of backflow. Finite spatial resolution is shown not to suppress the effect within realistic coarse-graining. These results establish
magnetic-field-controlled
quantum backflow in Landau systems as an accessible interference phenomenon.
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Materials Science
Topology-Stratified Materials Discovery with A Flow-Based Generative Model
Jingyi Zhou, Oyshee Chowdhury, Noah Oyeniran et al. (+1 more)
Accurate generation of
crystal structures is the foundation to the discovery of high-performance materials for extreme-environment applications, such as aerospace, additive manufacturing, and fusion energy systems. Although generative modeling has emerged as a promising approach for
crystal design, its performance remains limited by the complex
crystal structures and diverse chemical compositions. In this work, we develop UFO-MGen, a universal flow-based generative model that learns topological features of Wyckoff representations and leverages this information to accurately generate
crystals across vast structural and chemical spaces. Compared with state-of-the-art generative models, UFO-MGen achieves the highest
crystal generation success rate under a rigorous multi-stability evaluation framework, the highest SUN (stable, unique, novel) rate, and a remarkable extrapolation capability that has not been reported by previous models. Furthermore, a fine-tuning module is implemented to UFO-MGen for property-constrained
crystal generation, enabling the inverse materials design toward target properties. The UFO-MGen opens a new avenue for accelerated materials discovery and providing a foundation for universal materials intelligence.
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All authors Jingyi Zhou, Oyshee Chowdhury, Noah Oyeniran, Chongze Hu
High Energy Physics (Phenomenology)
Probing dark matter below the neutrino floor through NMSSM Higgs cascade decays at the HL-LHC
Yabo Dong, Kun Wang, Haijun Yang et al. (+1 more)
We investigate the potential of
Higgs cascade decays to probe neutralino dark matter below the
neutrino floor in the semi-constrained Next-to-Minimal Supersymmetric Standard Model with nonuniversal gaugino masses. We focus on lightest-neutralino masses of 65 to 100 GeV and study the process $pp\to H_2\to A_1A_1\to\gamma\gamma+\tilde{\chi}_1^0\tilde{\chi}_1^0$, where $H_1$ is the observed SM-like
Higgs boson, $H_2$ is a heavier CP-even state, and $A_1$ is the lightest CP-odd state. The selected parameter region lies near the $A_1$ resonance, with $m_{A_1}>2m_{\tilde{\chi}_1^0}$, allowing both resonantly enhanced neutralino annihilation and invisible $A_1$ decays. After imposing theoretical and experimental constraints, we find surviving samples with cascade signal cross sections of approximately 0.16 fb at $\sqrt{s}=14~\mathrm{TeV}$ even when their relic-density-rescaled
spin-independent scattering cross sections lie below the
neutrino floor. A Monte Carlo analysis of a representative
benchmark point yields an expected statistical significance of approximately $6.1\sigma$ at the high-luminosity LHC with an integrated luminosity of $3000~\mathrm{fb}^{-1}$, neglecting systematic uncertainties. These results highlight the potential of the diphoton plus missing transverse momentum channel as a complementary probe of neutralino dark matter.
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All authors Yabo Dong, Kun Wang, Haijun Yang, Jingya Zhu
Strongly Correlated Electrons
Neural Network Backflow with Low-Rank Multi-Determinant Updates
Tianshu Huang, Xiaowei Ou and Vidvuds Ozolins
Simulating strongly correlated
fermions remains a long-standing challenge due to the exponential complexity of the
Hilbert space and the intricate sign structure of many-body wavefunctions. We introduce a variational framework centered on a neural network backflow transformation that combines deep learning with variational Monte Carlo. The proposed ansatz employs a multi-determinant expansion with low-rank shifts to capture non-local correlations and complex sign structures. Applied to the two-dimensional Hubbard model at both half-filling and $1/8$ doping, the method achieves energies within $0.45\%$ of auxiliary-field
quantum Monte Carlo at half-filling and captures intertwined charge- and
spin-density stripe patterns at $1/8$ doping. These results demonstrate the potential of this framework as a scalable and interpretable approach to variational simulations of strongly correlated fermionic systems.
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High Energy Physics (Experiment)
Complementary Time- and Distance-Based Methods for Cosmogenic $^{9}$Li/$^{8}$He Background Estimation
Cailian Jiang, Qishan Liu, Liangjian Wen et al. (+4 more)
Cosmogenic $^{9}$Li and $^{8}$He isotopes constitute an important correlated background in low-energy
neutrino experiments because their $\beta$-delayed
neutron decay signatures can mimic inverse beta decay signals. Conventional estimates based on the time since the last
muon become challenging at high
muon rates, while
muon-related vetoes further reduce the residual isotope statistics. We extend the conventional time fit to an event-level
muon-categorized joint time (J-MuCAT) fit, which uses the time to the most recent preceding
muon in each energy-loss category. A complementary estimate is obtained from the candidate-to-
muon-track distance distribution (TraDiTS). The
muon-uncorrelated component is determined from the far-distance region and subtracted. This estimate is then used to constrain the J-MuCAT fit, defining the distance-constrained J-MuCAT (DCJ-MuCAT) fit. In detector-level simulation with successive cosmogenic-background vetoes, DCJ-MuCAT reduces the statistical uncertainty by more than $40\%$ relative to J-MuCAT and by more than $10\%$ relative to the TraDiTS. The fitted results remain consistent with the simulation truth. Applicability studies further show good performance over a broad range of
muon rates and isotope fractions. The proposed framework provides a practical approach for estimating residual $^{9}$Li/$^{8}$He backgrounds in large
neutrino detectors.
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All authors Cailian Jiang, Qishan Liu, Liangjian Wen, Gaosong Li, Zeyuan Yu, Wanlei Guo, Lei Zhang
Solar and Stellar Astrophysics
Catalogue of Solar Radio Bursts Detected by the LOFAR LV614 Station at the Irbene Observatory during Solar Cycle 25
Jānis Šteinbergs, Dmitrii Kolotkov, Valery M. Nakariakov et al. (+3 more)
A catalogue (https://doi.org/10.5281/zenodo.20157853) of
solar radio bursts detected with the LV614 LOFAR station at the Irbene Observatory, Latvia, in the stand-alone mode from June 2022 to August 2025 in the 29-60 MHz frequency range is presented. Observations were conducted with the weekly cadence, one-second time resolution, and 0.195 MHz spectral resolution. The cumulative duration of the observation was 1125.2 h. For all analysed observations, bandpass calibration was applied using Cassiopeia A as a reference source. In total, the catalogue includes 335
solar radio bursts.
Radio bursts of all five main types, I-V, were detected. Specifically, the catalogue contains parameters of 23, 8, 293, 6, and 5 bursts of Type I, II, III, IV, and V, respectively. The detected burst peak flux ranges from 0.3 SFU to 234 SFU. The catalogue provides information about the peak flux and frequency, and the estimated height of the source above the
solar surface. For Type II and III bursts, we also give the estimations of the frequency drifts, with mean values $ 0.043 ~\mathrm{MHz\,s^{-1}}$ and $4.383 ~\mathrm{MHz\,s^{-1}}$, respectively. We also estimated the fit $df/dt = Af^a$, with the best fit parameters $A=0.78$ and $a=0.43$. The numbers of Type I and III events are found to decrease with the peak flux, with the power law indices about $-0.9$ and $-1.25$, respectively. For Type III, we estimated electron beam speed ranging from 0.005 to 0.477 of the speed of light for the fundamental frequency, and 0.008 to 0.794 of the speed of light for its second harmonic.
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All authors Jānis Šteinbergs, Dmitrii Kolotkov, Valery M. Nakariakov, Vladislavs Bezrukovs, Pietro Zucca, Jānis Kaminskis
High Energy Physics (Phenomenology)
The compressed bino–wino dark matter in the GmSUGRA and the LHC soft-lepton searches
Imtiaz Khan, Ali Muhammad, Tianjun Li et al. (+2 more)
The search for electroweak supersymmetric particles remains an important part of the LHC program since neutralinos and charginos with masses around a few hundred GeV are still compatible with the present constraints in compressed spectra. Run-2 searches for the “golden channel”, $pp\to\widetilde\chi_2^0\widetilde\chi_1^\pm\to\widetilde\chi_1^0 Z^{(*)}\widetilde\chi_1^0 W^{\pm(*)}$, have reported mild excesses in parts of the soft two- and three-
lepton data, with the corresponding simplified-model interpretations emphasizing $m_{\widetilde\chi_2^0}\simeq m_{\widetilde\chi_1^\pm}\gtrsim200$~GeV and a neutralino mass difference near $20$~GeV. We study this configuration in the Minimal Supersymmetric Standard Model (MSSM) with the Generalized minimal Supergravity (GmSUGRA) boundary conditions, imposing the
Higgs,
flavor,
collider, relic-density and direct-detection constraints relevant to the spectrum. For both signs of $\mu$, the solutions compatible with the Planck experiment contain an almost pure bino $\widetilde\chi_1^0$ with mass about $260$–$266$~GeV and a nearly degenerate wino-like $\widetilde\chi_2^0/\widetilde\chi_1^\pm$ pair near $280$~GeV. The resulting splitting, $\Delta m_{21}\simeq18.5$–$19.1$~GeV, lies in the mass-difference region probed by the ATLAS and CMS soft-
lepton searches and places the $Z^{(*)}/W^{(*)}$ decays below the on-shell gauge-
boson thresholds. The same compressed hierarchy keeps the wino states thermally populated during freeze-out, so bino-wino coannihilation yields a neutralino relic abundance consistent with the Planck experiment while the surviving solutions remain compatible with the direct-detection experimental bounds. Thus, the GmSUGRA boundary conditions provide a high-scale realization of the compressed bino-wino spectrum relevant to the LHC soft-
lepton channel.
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All authors Imtiaz Khan, Ali Muhammad, Tianjun Li, Shabbar Raza, Mussawir Khan
Solar and Stellar Astrophysics
V844 Herculis: An Exceptional Intermediate Polar Hiding in an Ordinary Dwarf Nova
Anousha Greiveldinger, Peter Garnavich, Colin Littlefield et al. (+16 more)
We present time-series spectroscopy of the SU UMa-type
dwarf nova V844 Her during quiescence. We discover high-velocity Balmer and He I emission features modulated at a period of 29.3$\pm$0.1 minutes. The spectroscopic periodicity is identical to the photometric period detected only during superoutbursts. Interpreting this as the result of
magnetic accretion onto the white
dwarf, we identify V844 Her as an intermediate polar (IP). The
spin period of the white
dwarf is most likely to be 29.3 minutes. In a few IP systems, optical modulation is seen at twice the
spin frequency, so we can not rule out that the
spin period is 58.6 minutes. The orbital period of V844 Her is only 1.31 hr, meaning that the system has the shortest binary period and one of the smallest orbit-to-
spin ratios of the confirmed IPs. We present extensive optical, ultraviolet, and X-ray observations of V844 Her during the 2023 superoutburst. Compared with quiescence, the XRT count rate decreases during superoutburst. While the enhanced mass transfer during the superoutburst likely increases X-ray production, we propose that the drop in the count rate comes from the loss of soft X-rays due to an additional column from the outbursting disk.
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All authors Anousha Greiveldinger, Peter Garnavich, Colin Littlefield, Mark R. Kennedy, Paula Szkody, Jordan Tweddale, Mark Whittle, Teófilo Arranz, Donald Collins, James DeYoung, Sjoerd Dufoer, Charles Galdies, Jean-Francois Gout, Franz-Josef Hambsch, Emmanuel Kardasis, David Messier, Arto Oksanen, Gary Poyner, Richard Sabo
Mathematical Physics
An upper-symbol approach to $\Phi^4_d$ limits of Bose gases
Hao Liang
We study the high-temperature derivation of $\Phi^4_d$ measures from grand-canonical Bose gases on two- and three-dimensional
tori. Building on the upper-symbol variational approach of the author's earlier work, we use relative
entropy to give a simple, unified proof of relative free-energy convergence and
Hilbert–Schmidt convergence of all fixed-order rescaled reduced density
matrices to their Hartree counterparts. For interaction ranges $\varepsilon=\lambda^\eta$, where $\lambda$ is the inverse temperature, these results hold for every fixed $0<\eta<1/2$ in two dimensions and $0<\eta<1/26$ in three. In two dimensions, we improve the result of Jougla and Rougerie (2026) and the local $\Phi^4_2$ derivation of Fröhlich, Knowles, Schlein and Sohinger (2025). Combined with classical approximation, the two-dimensional result gives the first local $\Phi^4_2$ derivation valid for every fixed exponent $0<\eta<1/2$, allowing
polynomial exponents arbitrarily close to the diluteness threshold from below. In three dimensions, we use the identification of the local measure and the stationary SPDE estimates of Nam, R.~Zhu and X.~Zhu (2025). From these estimates we strengthen their classical correlation convergence to the
Hilbert–Schmidt norm. This yields the local limit at every fixed order in the same
polynomial range.
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Cosmology and Nongalactic Astrophysics
Gravitational-Susceptibility Dip Behind DESI's results: Addressing the Phantom Crossing by Local limit of Nonlocal Gravity
Aria Hemmatian, Yahya Mohammadi, Javad Tabatabaei et al. (+1 more)
The second data release of the Dark Energy Spectroscopic Instrument (DESI), based on more than fourteen million
galaxies and
quasars, prefers a dark energy component whose equation of state is dynamical. In the simplest two-parameter description of this behavior, the Chevallier–Polarski–Linder (CPL) parametrization, the data favor the quadrant $w_0>-1$, $w_a<0$, which implies that the equation of state crosses the phantom divide $w=-1$ at a
redshift $z\simeq0.4$. We show that the local limit of nonlocal
gravity, a teleparallel extension of general relativity governed by a scalar function called gravitational susceptibility $S(x)$, offers a natural explanation. In this model a cosmological constant is not allowed; dark energy is necessarily dynamical. The phantom crossing seen by an observer is an effective phenomenon generated by the time
evolution of $S(z)$. We establish a correspondence: to every general-relativistic dark energy model with equation of state $w(z)$, there corresponds a modified TEGR cosmology with $w=-1$ and a suitable susceptibility $S(z)$ that are indistinguishable at the level of the background expansion. We construct the susceptibility functions that reproduce the CPL behavior favored by DESI data, and we confront the model with the combined CMB,BAO, and SNe data using Boltzmann solver codes. The recovered susceptibility displays a characteristic low-
redshift dip with depth $\beta = -0.025 \pm 0.007$ at $z\simeq 0.4 $, and its derivative changes sign at a
redshift equal to the phantom-crossing epoch.
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All authors Aria Hemmatian, Yahya Mohammadi, Javad Tabatabaei, Shant Baghram
Quantum Physics
Tensor Network Simulation of Dynamic Circuits
Innocenzo Fulginiti, Alessandro Poggiali and Christian B. Mendl
Dynamic
circuits, which incorporate mid-
circuit measurements and classically controlled operations, extend the expressive power of
quantum programs and are central to applications such as
quantum error correction, state preparation, and distributed
quantum algorithms. However, their classical simulation is challenging due to the exponential growth of execution branches induced by mid-
circuit measurements. In this work, we develop a tensor network approach for simulating dynamic
circuits by extending a DMRG-based method for
quantum circuit simulation to support dynamic
circuit operations. To address the exponential proliferation of execution branches, we introduce and compare two strategies: a single-path
stochastic approach that samples individual measurement outcomes, and a multi-path approach that maintains an ensemble of branches. We
benchmark these methods on standard dynamic
circuits, including the teleportation protocol and GHZ state preparation, as well as on random dynamic
circuits. Our analysis explores the trade-offs between simulation accuracy and computational efficiency. These results provide a practical and scalable framework for the classical simulation of dynamic
circuits.
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Chaotic Dynamics
Exploring chaotic properties in the nonlinear Walecka Model
Luiz Antônio Barreiro and André L. P. Livorati
This paper investigates dynamical properties of the Nonlinear Walecka Model (NLWM), also known as
Quantum Hadrodynamics (QHD), which provides a relativistic framework for describing
nuclear matter through nucleon-
meson interactions. While the original linear model successfully captures qualitative features of
nuclear matter, it overestimates
nuclear compressibility; consequently, nonlinear extensions incorporating cubic and quartic self-interaction terms in the scalar field $(\sigma)$ are employed to achieve better agreement with experimental data. By treating the self consistent effective-mass equation as an iterative mapping, the study explores the emergence of complex behaviors such as periodic orbits and chaotic regimes. Using tools from nonlinear dynamics, including return maps and bifurcation diagrams, we characterize routes to chaos via period doubling cascades and identify the presence of "shrimps" stable isoperiodic islands within chaotic regions of the parameter space. Furthermore, we discusses the physical implications of these findings, suggesting that crisis phenomena and structural convergence may serve as dynamical signatures of macroscopic rearrangements in the scalar mean field, potentially influencing the stability and equation of state (EOS) of dense
nuclear matter in extreme environments like
neutron stars.
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Materials Science
Deep Generative Crystal Structure Prediction: A Benchmark Study and a Controlled Test of Prototype Dependence
Lai Wei, Rongzhi Dong, Ying Feng et al. (+2 more)
Deep generative models are widely reported to enable de novo
crystal structure prediction (CSP), but their capability has not been measured consistently against template-based methods. We evaluate 12 representative generative CSP models, spanning latent-variable,
diffusion, flow-matching, autoregressive, and
manifold random-walk architectures, against TCSP 2.0 on 180 test structures and a leakage-controlled subset of 46. All methods use identical structure-matching,
symmetry, and consensus criteria. Template
retrieval is the strongest single method, reaching 68.3% top-1 success;
symmetry-aware EquiCSP (66.4%) and Uni-3DAR (62.9%) form the next tier. However, comparison with TCSP 2.0 shows that most structures correctly predicted by generative models are also correctly predicted by template substitution. Thus, the set of structures uniquely reachable by generation is small, limiting its practical advantage for discovering structures outside existing prototype libraries. To test the source of this performance, we removed entire stoichiometric prototype families from the training set and retrained the strongest generative model. Accuracy declined by 50-78% across four families, establishing that performance is substantially prototype-dependent. A small minority of structures survived removal of their prototype family, demonstrating a real but limited
retrieval-independent predictive capacity. Present generative CSP models therefore function largely as implicit, softer-edged prototype libraries rather than genuinely de novo predictors. Enlarging this residual capacity, rather than aggregate match rate alone, is the central open problem.
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All authors Lai Wei, Rongzhi Dong, Ying Feng, Madeline Miklos, Jianjun Hu
High Energy Physics (Phenomenology)
Nonthermal fixed point for massless scalar field theories
Viktoria Noel, Chuang Huang, Aleksandr N. Mikheev et al. (+1 more)
We compute universal scaling exponents and scaling functions for massless scalar field theories far from
equilibrium. Using a large-$N$ expansion to next-to-leading order, we investigate the nonperturbative infrared behaviour associated with the transport of a) energy or b) effective particle number towards low frequencies $\omega$ and momenta $\bar p$. For massless dispersion $\omega = \bar{p}$, we determine the scaling form of the distribution function whose universal power-law tail $f_S(\bar p) \sim 1/\bar{p}^\kappa$ is found to be a) $\kappa = d+1$ and b) $\kappa = d$ in $d=3$ spatial dimensions. Our results establish that relativistic and nonrelativistic theories do not belong to the same universality class in this case, which opens up new applications to far-from-
equilibrium phenomena in high-energy and (
quantum) many-body physics with linear dispersions.
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All authors Viktoria Noel, Chuang Huang, Aleksandr N. Mikheev, Jürgen Berges
Strongly Correlated Electrons
Extraordinary Lifetime Enhancement of Coherent Phonon-Amplitude Modes in the Excitonic Insulator Phase of Ta2Pd3Te5
Anjan Kumar N M, Shuhan Wang, Snehashish Chatterjee et al. (+9 more)
The excitonic
insulator (EI) is an electronic phase of condensed
excitons. However, in many prototypical materials the presence of a concurrent structural transition complicates the identification of a purely electronic origin of the ordered state. Here, we investigate Ta2Pd3Te5, in which an EI phase develops below TC ~ 100 K in the absence of a detectable structural transition. We characterize the excitonic condensate via its coherent
phonon-amplitude response. Most strikingly, an extraordinarily strong lifetime enhancement of these modes sets in below TC which we establish as a new and robust fingerprint linked to
exciton condensation. We discuss possibilities to capture the enhancement when taking into account a coupling of excitonic and
lattice effects in line with the coupled
phonon-amplitude response. Within an order-parameter polaron picture coupling to the excitonic state may dress the
phonon mode and thereby suppress its relaxation and a phenomenological model combines the anharmonic
phonon response and a reduced electronic scattering due to the gap opening in the EI phase.
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All authors Anjan Kumar N M, Shuhan Wang, Snehashish Chatterjee, Yan Zhu, MinJae Kim, Tobias Ritschel, Elaheh Sadrollahi, Jochen Geck, Achim Rosch, Chandra Shekhar, Claudia Felser, Stefan Kaiser
Astrophysics of Galaxies
Exploring the influence of reionisation-era galaxies on their local intergalactic medium using the Sherwood-Relics simulations
Hamish Anderson, Laura C. Keating, Luke Conaboy et al. (+3 more)
Recent surveys have detected excess flux in the Lyman-$\alpha$ forest of
quasar spectra several Mpc from high-
redshift line-emitting
galaxies, indicating a correlation between intergalactic medium (IGM) transmission and reionisation-era
galaxies. We examine the
galaxy-IGM connection using the Sherwood-Relics simulation suite, a set of hybrid radiation-hydrodynamic simulations that model the IGM at high
redshift. We simulate the Lyman-$\alpha$ forest and a population of mock [OIII] emitters using the survey specifications of JWST's ASPIRE programme. We measure the
evolution of the effective optical depth in regions close to
galaxies, and contrast this with a control sample probing the random IGM. We characterise the changing physical properties of the IGM to explain the observed sightline-to-sightline scatter in opacity between 5.4 < $z$ < 6.2. We find that the IGM is more opaque than average at small radii ($r$ $\leq$ 5 cMpc/$h$) close to
galaxies, as these regions are overdense. At larger radii (15 < $r$ $\leq$ 50 cMpc/$h$), the IGM is more ionised than average, due to the higher photoionisation rate near
galaxies. We find qualitative agreement with the observational results from ASPIRE, though we see large realisation-to-realisation scatter driven by
cosmic variance, as also seen in theoretical explorations of the
galaxy-Ly$\alpha$ transmission cross-correlation function. Our results generally agree with observations claiming that there is a large-scale ionisation bias around [OIII] emitters, supporting the idea that their role is significant in shaping the properties of the IGM during reionisation.
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All authors Hamish Anderson, Laura C. Keating, Luke Conaboy, Xiangyu Jin, James S. Bolton, Ewald Puchwein