High Energy Physics (Phenomenology)
Detector performance at SHiP for cascade-produced long-lived particles
Matei Climescu, Yehor Kyselov and Maksym Ovchynnikov
Previous studies have shown that cascade production in the thick target of the SHiP experiment may substantially enhance the number of light long-lived particles (LLPs) decaying in the fiducial volume. However, cascade-produced LLPs are typically soft, so daughter-level acceptance and reconstruction effects can strongly suppress the observable event rate. We quantify this suppression for two representative cases: photophilic
axion-like particles produced in electromagnetic cascades, and heavy neutral
leptons produced in decays of secondary kaons. We combine a semi-analytic event-rate calculation with a detector-level study of ALP reconstruction in the electromagnetic calorimeter. For the nominal SHiP detector design, cascade ALPs give at most a moderate enhancement over primary production, and only at the lightest masses; at higher masses, the cascade contribution becomes subdominant or negligible. For HNLs from secondary kaons, the cascade contribution is already subdominant after imposing daughter-level
geometric acceptance. We also identify possible ways to recover part of the cascade event rate, including relaxed event-selection criteria and an active-target subdetector.
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High Energy Physics (Phenomenology)
Core Composition Effects on the QCD Axion Mass Limit from Neutron Star Cooling
Fernando Arias-Aragón and Federico Nola
Neutron stars are very dense media in which
axions may be produced. This has been used to set a limit on the QCD
axion mass, usually under the assumption that only
neutrons,
protons, electrons, and
muons appear in the
star core. Given the extreme conditions reached within
neutron stars, it is reasonable to consider that other particles, such as hyperons and $\Delta$ resonances, may appear in the
neutron star core. In this work, we study how the limit on the mass of QCD
axions, namely KSVZ and DFSZ invisible
axions, is altered when different equations of state are used, allowing for heavier particles to appear in the
neutron star core. We find that this dependence is in general mild and thus reinforces the reliability of the known limit. Additionally, in the DFSZ scenario, it may drive the limit within the sensitivity window for IAXO. This would allow this experiment to discern the composition of
neutron star cores if an
axion were to be observed within that window.
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Astrophysics of Galaxies
Clumps in a Cocoon: Geometry and Mixing Set the Universal X-ray to H$\alpha$ Surface Brightness Ratio
Zirui Chen, S. Peng Oh, Drummond B. Fielding et al. (+3 more)
Recent observations reveal a nearly universal X-ray to H$\alpha$ surface-brightness ratio, ${\rm SB}_{\rm X}/{\rm SB}_{\rm H\alpha}\sim 3$, in
galactic winds, ram-pressure-stripped tails, and cluster filaments. This is surprising, given the very different temperatures traced by the X-ray and H$\alpha$ emission. Plane-parallel mixing-layer models do not recover this ratio. We run 3D wind-tunnel simulations in the high density-contrast ($\chi\sim 10^3$) regime, where the cold phase shatters into small H$\alpha$-emitting clumps embedded in a volume-filling X-ray cocoon. After smoothing on the tail-width scale, the simulated ratio converges to the observed value. The hot-gas entrainment rate sets the bolometric luminosity, $L_{\rm bol} \propto \dot{M}_{\rm in}$. H$\alpha$ carries a nearly fixed fraction of this luminosity, set mainly by atomic emissivity near $10^4$ K. The X-ray-emitting mass is the same entrainment rate multiplied by the residence time in the X-ray-emitting temperature band, and its luminosity is the corresponding thermal energy divided by the cooling time. Hence $L_{\rm X} \propto \dot M_{\rm in} \propto L_{\rm bol}$, with the X-ray fraction set by the residence-to-cooling-time ratio. An age diagnostic constrains the residence time to be far shorter than the cooling time, making the X-ray and H$\alpha$ fractions comparable. Their common scaling with $L_{\rm bol}$ explains the correlation, while the comparable bolometric fractions explain why the observed ratio is order unity.
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All authors Zirui Chen, S. Peng Oh, Drummond B. Fielding, Lachlan Lancaster, Yuan Li, Brent Tan
Mesoscale and Nanoscale Physics
Phase diagram of magnetic $S^3$ Skyrmions on three-dimensional lattices and the toroidal antiSkyrmion
Niccolò Francini, Stefano Bolognesi, Sven Bjarke Gudnason et al. (+1 more)
Magnetic Skyrmions are planar
solitons stabilized by the Dzyaloshinskii-Moriya interaction (DMI) and realized in
chiral magnets. We study their natural three-dimensional generalization: a sigma model from $\mathbb{R}^3$ to $S^3$ with a four-component magnetization vector, stabilized by a one-derivative term which is a generalized DMI. We utilize two SO(3)-invariant generalized DMIs discovered recently: an "$\alpha$-term" supporting a spherically symmetric hedgehog Skyrmion and a "$\beta$-term" supporting an axially symmetric Skyrmion that splits into two half-Skyrmions connected by a
magnetic string of negative tension, a phenomenon we call "anti-confinement". We derive a cubic-
lattice discretization that reproduces both continuum theories at long wavelengths and use Monte Carlo simulations to map the finite-temperature phase diagram. We identify
spin-spiral,
magnetic-string-
lattice, Skyrmion-
lattice, and antiSkyrmion-
lattice phases, as well as a mixed-
topology regime with fractional $S^3$ charges localized at string bends. We find, for the first time in the literature to the best of our knowledge, a toroidal (anti-)
soliton of unit charge. Our results establish a theoretical and computational framework for three-dimensional topological
magnetic textures in systems whose order-parameter
manifold is $S^3$.
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All authors Niccolò Francini, Stefano Bolognesi, Sven Bjarke Gudnason, Roberto Menta
High Energy Physics (Phenomenology)
Searches for GeV-Scale ALPs at RHIC
Kaori Fuyuto, Claudio Andrea Manzari and Hitoshi Murayama
We point out that ultra-peripheral Au+Au collision data collected at the Relativistic Heavy Ion
Collider, operational during 2000-2026, can be used to search for
axion-like particles coupled to
photons via the resonant process $\gamma\gamma \to a \to \gamma\gamma$. Exploiting the $Z^4$ enhancement of the two-
photon luminosity in heavy-ion collisions and the low
photon energy thresholds achievable at RHIC, we simulate signal and background processes, the latter dominated by light-by-light scattering, hadronic resonance production, and misidentified $e^+e^-$ pairs, and estimate upper limits on the ALP-
photon coupling $g_{a\gamma\gamma}$ assuming $1.9~\text{nb}^{-1}$ of existing data collected by the PHENIX experiment. We find sensitivity to ALP masses in the range $2~\text{GeV} \lesssim m_a \lesssim 5~\text{GeV}$ with couplings $g_{a\gamma\gamma} \gtrsim 4\times 10^{-4}~\text{GeV}^{-1}$, probing previously unexplored regions of parameter space. Access to larger luminosity
datasets could substantially extend the sensitivity of this search, motivating a dedicated analysis of ultra-peripheral collision data collected at RHIC by PHENIX as well as other experiments.
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High Energy Physics (Theory)
New Exotic Operators in the Spectrum of Wilson Lines in General Representations
Daniele Artico, Carlo Meneghelli, Michele Savi et al. (+1 more)
Wilson lines are fundamental probes of gauge theories. We show that, in sufficiently rich representations, they support a large new class of operator insertions. For half-BPS lines in $\mathcal{N}=4$ SYM, some have the
quantum numbers of the displacement supermultiplet and define natural defect deformations. By relating their beta-functions to
chiral ring OPE coefficients, we show that these deformations are marginally irrelevant, meaning the half-BPS line is IR stable for all representations. We connect these deformations to multidimensional RG flows and find evidence for new conformal line defects.
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All authors Daniele Artico, Carlo Meneghelli, Michele Savi, Rudolfs Treilis
High Energy Physics (Theory)
Moduli spaces of type II twists
Fabian Hahner
We provide a complete classification of twisting supercharges for type IIA supergravity in a flat background by determining the orbits of square-zero elements in the $\mathcal{N}=(1,1)$ super Poincaré
algebra in ten dimensions under the action of the
Spin group. Together with recent results for type IIB, this completes the description of the
moduli space of twists for type II supergravities. We show that the type IIA nilpotence variety is the union of the eleven-dimensional nilpotence variety and a second component, confirming a
conjecture of Eager, Saberi, and Walcher, and determine which twists of type IIA arise via dimensional reduction. Using the pure spinor formulation of the superstring, we construct maps from the
moduli spaces of worldsheet twists to those of target space twists for both type IIA and type IIB, and find that these maps are not surjective. Precisely those twists of supergravity whose stabilizers are special holonomy groups—$G_2$ in type IIA, $\mathrm{Spin}(7)$ and $\mathrm{Sp}(4)$ in type IIB—have no corresponding background on the pure spinor worldsheet. Finally, we work out the action of T-duality relating twists of type IIA and type IIB, and find an obstruction to dualizing the $G_2$-twist of type IIA along certain directions.
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Quantum Physics
Exact metastability in a class of driven-dissipative quantum many-body systems
David D. Noachtar and Aashish A. Clerk
Metastability in many-body
quantum systems and its associated exponentially-long timescales have been the subject of considerable recent interest. Here, we focus on a class of driven-dissipative many-body open
quantum systems described by a Lindbladian having hidden time-reversal
symmetry (a form of
quantum detailed balance). Examples include boundary-driven interacting
spin chains, bosonic
lattice models and driven-dissipative collective
spin models. We suggest that for such systems, slow timescales in the vicinity of a dissipative first-order phase transition can be analytically predicted using a special purification of the non-
equilibrium steady state. We show the accuracy of our
conjecture through detailed studies of a dissipative transverse-field Ising model with collective and local decay, and a driven-dissipative nonlinear cavity model. Our results allow quantitative insights into metastability and slow dynamics for a range of systems, including cases where semiclassical or path-integral instanton approaches are intractable.
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High Energy Physics (Phenomenology) · Cross-listed from math.NT
Arithmetic Symmetry in Ideal Prouhet-Tarry-Escott Solutions
Yu-Dai Tsai, Junseok Lee and Fuminobu Takahashi
Motivated in part by anomaly cancellation for integral charge spectra in
chiral gauge theory, we study the symmetric locus in the ideal degree-three Prouhet-Tarry-Escott problem. A symmetric integer solution is one whose entries are paired about a common center $c\in \frac12\mathbb Z$. This
symmetry reduces the problem to a sum-of-two-squares equation, $x^2+y^2=u^2+v^2$, in integer variables, subject to the appropriate parity conditions. Thus the problem is governed by representations as sums of two squares. For the full symmetric locus, let $N_{\mathrm{sym}}(H)$ denote the number of nontrivial symmetric integer solutions of height at most $H$, counted with unordered multiset conventions and summed over the admissible centers. Then \begin{align*} N_{\mathrm{sym}}(H) = \frac{4\log 2}{3\pi^2}H^3\log H+O(H^3). \end{align*} The logarithmic enhancement comes from the second moment of the sum-of-two-squares representation function. In particular, the symmetric locus is larger than one would expect from the naive $H^3$ degree-weighted box-counting scale alone. This asymptotic identifies a large arithmetically structured subfamily of the ideal degree-three solution space, and suggests that paired anomaly-free integral charge spectra reflect a fundamental number-theoretic structure.
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Quantum Physics
Exploring the landscape of compact magic-state distillation factories
Hugo Jacinto, Xavier Valcarce, Victor Barizien et al. (+2 more)
Producing high-fidelity magic states using the smallest possible number of physical
qubits and operations stands as a very important challenge to achieve fault-tolerant
quantum computation at scale. Besides emerging proposals for alternative methods such as cultivation, magic state
distillation remains essential for achieving very low error rates. Known
distillation protocols are usually built through
quantum codes derived from triorthogonal
matrices. Here, exploiting the specific noise structure present in magic state
distillation protocols, we show that classical error-correcting codes offer a simpler framework for deriving these protocols. This formulation is particularly well suited to systematic numerical and analytical studies of
distillation protocols involving a fixed number of
qubits. Specifically, we use a SAT solver to derive a series of no-go
theorems that relate key figures of merit, including the number of
qubits and the factory distance. In particular, considering the standard implementation as a
circuit of Z-diagonal Pauli product rotations followed by measurements, we show that no $T$-to-$T$
distillation protocol on fewer than eight
qubits can exceed distance 3, and no $T$-to-$\mathrm{CC}Z$ protocol distance 2. Our results also include new such
distillation protocols with the smallest number of
qubits for a given distance in the literature, namely distance 4 and 5 $T$-to-$T$ protocols supported on 10 and 11
qubits, as well as distance 3 and 4 $T$-to-$\mathrm{CC}Z$
distillation protocols supported on 9 and 10
qubits. Finally, going beyond
unitary circuits by recycling
qubits through mid-
circuit measurement and reinitialization, we obtain an implementation of the distance-5 $49T$-to-$1T$ protocol on only 5 active
qubits.
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All authors Hugo Jacinto, Xavier Valcarce, Victor Barizien, Élie Gouzien, Nicolas Sangouard
High Energy Astrophysical Phenomena
The Effects of Cosmic Ray Protons on Galactic Nonthermal Filaments
Mohan Richter-Addo, Roark Habegger, Ellen Zweibel et al. (+2 more)
The
Galactic Center (GC) contains a collection of filaments that are typically tens of parsecs in length, illuminated by synchrotron radiation from
cosmic rays (CR). The origin of these nonthermal filaments (NTFs) is unclear. We aim to distinguish two injection mechanisms: the first mechanism posits that NTFs are fueled either by jets from
pulsar wind nebulae and are
lepton-dominated; the second mechanism posits that NTFs are fueled by accelerated particles from interstellar shocks and are
proton-dominated. We explore these mechanisms using the magnetohydrodynamics (MHD) code Athena++, modified to account for radiative and collisional losses, to simulate CR propagation with
lepton and
proton CR species. We vary parameters such as
magnetic field strength,
plasma density, and the CR
diffusion coefficient to determine how the range of conditions present in the GC can affect CRs' propagation, heating,
plasma flow, and the observed synchrotron emission. We find few observable differences between the
proton- and
lepton-dominated cases, but comparing the models with observed filament properties motivates consideration of a third formation mechanism: the generation of NTFs arise from intermittent structures in
Galactic Center
turbulence.
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All authors Mohan Richter-Addo, Roark Habegger, Ellen Zweibel, Dylan M. Paré, David T. Chuss
Nuclear Theory
NICER constraints on low density matching and high density continuation in neutron star equations of state
Federico Nola
We investigate whether current astrophysical data constrain not only the high-density continuation of the
neutron star equation of state, but also the low density matching procedure itself. To this end, we compare two low density branches propagated through a common high density extension and confront them with direct NICER mass-radius posteriors, a lower bound on the maximum mass and an effective constraint on $\Lambda_{1.4}$. We find that the observable predictions of the two branches remain strongly overlapping, while the NICER-informed posterior still induces a nontrivial constraint on the matching parameters. Current data therefore constrain primarily the shared continuation above $n_1$, but also indirectly restrict the low density matching sector.
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High Energy Astrophysical Phenomena
The X-ray-to-UV relation does not evolve in homogeneous quasar samples
G. Risaliti, E. Lusso, E. Nardini et al. (+6 more)
We present a new, highly homogeneous
quasar sample with X-ray and UV observations optimized to reliably estimate distances via the non-linear X-ray-to-UV relation. Cross-matching the Sloan Digital Sky Survey DR16
quasar catalog with the XMM-Newton serendipitous catalogue (4XMM–DR14), we employ strict selection criteria to build a robust sample: (1) UV and (2) X-ray colour constraints to avoid, respectively, extinction and absorption; (3) removal of broad absorption line and
radio-bright
quasars; (4) exclusion of sources at z<0.7 to prevent
galactic UV contamination; and (5) rejection of sources with shallow X-ray observations. The latter step, closely related to the Eddington bias, is critical because SDSS data are generally deeper than X-ray data for typical
quasar spectral energy distributions: ignoring such a discrepancy introduces a spurious
redshift dependence in the X-ray-to-UV relation parameters. Our final sample contains about 2,000
quasars at z=0.7–5. We demonstrate that the X-ray-to-UV relation is constant across this
redshift range, with a mean slope of 0.58\,$\pm$\,0.01 and a dispersion of 0.15 dex. Our findings confirm the intrinsic stability of this relation over
cosmic time, emphasizing that both homogeneity and robust Eddington bias corrections are vital for flux-limited samples. In fact, the impact of the preferential detection of X-ray brighter-than-average sources near the effective sensitivity limits significantly grows with
redshift. Any resulting evolutionary trend in the X-ray-to-UV relation, especially in the form a slope flattening, is therefore either a largely spurious effect, or the result of mixing populations of
quasars with intrinsically different spectral properties.
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All authors G. Risaliti, E. Lusso, E. Nardini, C. Niccolai, M. Ralowski, A. Sacchi, A. Shlentsova, M. Signorini, B. Trefoloni
Quantum Physics
Benchmarking Quantum Algorithmic Resilience for CVaR Portfolio Optimization: The Expressibility-Coherence Trade-off
Prashik N. Somkuwar, K. Srinivasan and G. Raghavan
Quantum combinatorial optimization offers theoretical advantages for complex financial modeling, but physical implementation on Noisy Intermediate Scale
Quantum (NISQ) devices is severely constrained by hardware
topology. This study presents a hardware benchmarking analysis between a Hardware Efficient Variational
Quantum Neural Network (HE-VQNN) and the Warm Start
Quantum Approximate Optimization
Algorithm (WS-QAOA) for a hybrid Mean Variance and Conditional Value at Risk (CVaR) portfolio objective. By implementing a novel classical
quantum hybrid proxy
matrix to bypass the CVaR auxiliary
qubit bottleneck, we map up to 16 assets from the NIFTY 50 index onto an IBM heavy hex processor. We systematically quantify algorithmic resilience to the "SWAP tax" incurred during routing. Empirical results reveal a critical operational trade-off: WS-QAOA provides exact theoretical mapping but suffers catastrophic hardware decoherence due to exponential nonlocal gate overhead. Conversely, HE-VQNN preserves hardware coherence but lacks the mathematical expressibility to capture dense tail risk asset correlations. This study exposes the limitations of dense financial optimization on current architectures forces an nonviable choice between algorithmic inexpressibility and hardware decoherence. This is indicative of a deeper limitation as to what can and cannot be done with NISQ computers lacking in all-to-all connectivity.
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Geophysics
GNSS-FM: A Self-Supervised Foundation Model for Daily GNSS Displacement Time Series
Nick Teutschmann, Laura Crocetti, Fanny Lehmann et al. (+2 more)
Displacement time series from Global
Navigation Satellite Systems (GNSS) are essential for a wide range of applications, including monitoring tectonic crustal deformations and investigating the different stages of the earthquake cycle. Machine learning methods have proven promising for GNSS applications; however, most remain fully supervised. This creates a bottleneck as labeled data are scarce, even though large amounts of unlabeled GNSS data are freely available. We present GNSS-FM, a self-supervised foundation model for daily GNSS time series. The model uses a dual-stream input combining displacement and velocity-like increments, and is pretrained using a masked latent prediction objective with vector-quantized targets adapted from wav2vec 2.0, with several modifications for geodetic data. Pretrained on data from over 17,000 globally distributed GNSS stations, an analysis of the learned codebook suggests that the representations capture the main signal types in GNSS displacement data, including seismic offsets, tectonic drift, and seasonal patterns. The foundation model is later fine-tuned on two downstream tasks, namely 90-day displacement
forecasting and seismic step localization, where it outperforms strong task-specific baselines in both cases. These results show that self-supervised pretraining is a promising approach for GNSS time series analysis.
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All authors Nick Teutschmann, Laura Crocetti, Fanny Lehmann, Leonardo Trentini, Benedikt Soja
Materials Science
MatMind: A Structure-Activity Knowledge-Driven Generative Foundation Model for Materials Science
Zhan'ao Yao, Boxuan Zhang, Jingyuan Shu et al. (+10 more)
Progress in AI-driven
crystal materials science has so far been carried by narrow architectures purpose-built for individual tasks – graph neural networks for property prediction,
diffusion and flow-matching models for
crystal generation – each excelling within its niche yet unable to act as a shared backbone across the full spectrum of materials problems. Generative large
language models offer a fundamentally different paradigm, in which structural representation, quantitative prediction, and structure-activity
reasoning can be unified within one model, but the materials community has yet to see this paradigm realized at a level competitive with established narrow specialists. Here we present MatMind, a generative foundation model purpose-built for
crystal materials science under this paradigm, developed through the coordinated activation of structure-activity knowledge and physics-informed feedback within a progressive training framework – combining structure-activity knowledge injection, a dual-head architecture that jointly trains
language reasoning and numerical regression in a shared representation space, and multi-objective physics-informed reinforcement learning over stability, novelty, and structural diversity. Across three task families, MatMind attains the lowest mean absolute error on energy above hull, bulk modulus, and band gap – surpassing graph neural network predictors purpose-built for these tasks – reaches an S.U.N. rate of 65.3% on unconditional
crystal generation, and achieves a comparable multiplicative improvement on magnetization-density-conditioned generation, where only 21 positive samples exist within over 600000 training entries. By matching or surpassing narrow specialists on their own ground while operating within a single unified model, MatMind shows that the LLM-based paradigm can serve as a viable backbone for
crystal materials science going forward.
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All authors Zhan'ao Yao, Boxuan Zhang, Jingyuan Shu, Xiaoyu Wu, Rongyan Wang, Linjing Li, Dajun Zeng, Yudong Yao, Tingwei Chen, Youwei Wang, Xiaolin Zhao, Jiahui Shi, Jianjun Liu
Quantum Physics
Correlation-Assisted Odd-Parity Encoded Gates in Coupled Fluxonium Qubits under Non-Markovian TLS Noise
Chenghong Ji and Chaoying Zhao
Correlated longitudinal noise can be partially converted into common-mode fluctuations in an oddparity two-
qubit subspace. We analyze an encoded logical
qubit formed by the states in two coupled fluxonium
qubits. Projecting the exchange-coupled two-
qubit Hamiltonian onto this subspace yields an effective logical
Hamiltonian in which the exchange interaction drives XL rotations and the
qubit detuning drives ZL rotations. We model correlated two-levelsystem (TLS) noise by using longitudinal
stochastic processes with finite
memory time and evaluate encoded-gate performance through the average gate fidelity. Within the projected model, positive spatial noise correlation suppresses the differential fluctuation and thereby improves the fidelity of encoded logical gates. We further compare Gaussian Ornstein-Uhlenbeck, Markovian, and randomtelegraph noise models and examine the role of logical dynamical decoupling. These results identify a noise-adapted control mechanism for odd-parity encoded operations in coupled fluxonium devices and motivate future multilevel simulations including leakage and pulse-level constraints.
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Atmospheric and Oceanic Physics
TianJi-Environ: An Autonomous AI Scientist for Atmospheric Environmental Research
Haoluo Zhao, Hongchun Zhang, Nan Li et al. (+6 more)
As atmospheric environmental prediction continues to improve, interpretable validation of pollution mechanisms and feedback processes has become a main challenge in atmospheric chemistry. Yet mechanism validation based on complex numerical models still relies heavily on expert knowledge: mechanistic hypotheses must be operationalized into executable experiments, and model outputs must be organized into traceable evidence. We present TianJi-Environ, an auditable AI Scientist for atmospheric-chemistry mechanism validation. TianJi-Environ establishes the first WRF-Chem-based multi-
agent framework that autonomously drives complex atmospheric-chemistry simulations, converting mechanistic hypotheses into executable configurations, testing experiments, and evidence criteria. Using ozone response and particulate-matter feedback as two representative examples, we demonstrate TianJi-Environ's capability for mechanism validation. In a summertime ozone case over the North China Plain, the system detects directionally consistent aerosol-radiation-interaction signals in shortwave radiation and boundary-layer height, but judges the evidence for ozone response to NOx control to be incomplete. In a wintertime PM2.5 case over the Guanzhong Basin, it localizes the unsupported link to insufficient propagation from black-carbon perturbation to particulate response and missing diagnostics of vertical absorptive heating. These results show that TianJi-Environ makes expert-driven mechanism validation explicit, structured, and auditable, offering a reproducible paradigm for multi-
agent systems coupled with complex atmospheric-chemistry models.
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All authors Haoluo Zhao, Hongchun Zhang, Nan Li, Jing-Jia Luo, Kaikai Zhang, Mengyang Yu, Nan Chen, Tao Song, Fan Meng
Medical Physics
Time-Resolved Stress Analysis of Tissue Simulants During Needle-Free Jet Injection
Kohei Yamagata, Prasad Sonar, Kazuhiro Terai et al. (+2 more)
Needle-free jet injection generates transient internal stress fields that can influence tissue deformation, pain-related stimulation, and cellular-level mechanical responses. However, the penetration mechanics have often been inferred from cavity deformation and interpreted mainly as shear-dominated behavior. In this study, high-speed photoelastic measurements were used to visualize and quantify optically integrated stress responses in a 5 wt% gelatin tissue simulant during penetration by two needle-free injectors with different actuation mechanisms: the Actranza Lab, a pyro-drive injector driven by cartridge-based combustion, and the Biojector 2000, a commercially available CO$_2$-driven injector. A polarization camera operated at 60,000 fps was used to obtain the phase difference and principal stress orientation, allowing evaluation of the photoelastic stress-intensity response and its decomposed normal- and shear-stress-related components. Under the same injection volume of 20 $\mu$L, the Actranza Lab formed a narrow, depth-oriented cavity, whereas the Biojector 2000 produced a wider, bulged cavity. In both cases, a clear normal-stress-difference component developed around the cavity. This component became comparable to or greater than the shear-stress component for the Actranza Lab and became dominant during the later cavity-bulging stage for the Biojector 2000. These results show that needle-free jet penetration cannot be described solely by shear stress; instead, injector-dependent cavity dynamics generate multi-component tissue loading. The findings provide an engineering basis for evaluating needle-free injector performance and for designing systems that improve delivery while reducing mechanical burden on tissue.
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All authors Kohei Yamagata, Prasad Sonar, Kazuhiro Terai, Yuto Yokoyama, Yoshiyuki Tagawa
Strongly Correlated Electrons
Non-Abelian braiding in Abelian Fractional Quantum Hall Phases from realistic interactions
Ha Quang Trung and Bo Yang
We propose a method of realizing non-Abelian braiding of fractionalized quasiholes in the Laughlin fractional
quantum Hall phase at $\nu=1/3$ with realistic two-body interactions within the lowest Landau level. It is numerically shown that low-lying gapped excitations near $\nu=1/3$ are contained almost entirely within the null space of the three-body Moore-Read model
Hamiltonian. They are thus
quantum fluids of non-Abelian quasiholes that are in principle physically accessible. In particular, Laughlin ground state can be described as a fluid of “$\psi$-type" quasiholes formed by binding a
magnetic flux with a Majorana
fermion (MF), and the Laughlin quasiholes are described by the “$1$-type” quasiholes, which are
magnetic fluxes without a MF attached. Within the Laughlin phase, Laughlin quasiholes can be locally fractionalized into non-Abelian quasiholes, when the strong attraction between them is overcome by properly designed one-body electronstatic trapping potentials. Extensive numerics with proper finite-size scaling corroborate this physical picture, and our study points to the possibility of realizing non-Abelian braiding within an Abelian topological phase in experiment without the need for fine-tuning realistic electron-electron interaction.
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Earth and Planetary Astrophysics
GJ 3929 b as the First Complete Rocky Worlds DDT Data Set
Nicholas J. Connors, Christopher Monaghan, Björn Benneke et al. (+2 more)
Despite their large abundance, it is still unknown whether and under what conditions rocky
planets around M
dwarf stars can host atmospheres. This open question motivated the on-going Rocky Worlds DDT survey focused on searching for atmospheres on relatively low-temperature rocky
exoplanets by systematically probing for the presence of day-night heat redistribution and CO2 absorption through JWST/MIRI 15 $\mu$m eclipse observations. Here we present the analysis of the first full data set from this survey, consisting of four observations of the warm Earth-size
exoplanet GJ 3929 b, with a planetary mass of 1.75+0.44-0.45 M$_\oplus$ and instellation flux of 17.3+/-0.7 S$_\oplus$. In our analysis, we include two previously unpublished eclipse observations and find an overall eclipse depth of 118+/-22 ppm and a dayside surface brightness temperature of 641+59-64 K. This is marginally lower than the eclipse depth of 160+26-27 ppm previously reported based on only the first two observations. While the full data set remains consistent with bare rock scenarios, it also leaves more room for thin atmosphere scenarios. Only thick CO2 atmospheres without thermal inversion remain ruled out at greater than 3$\sigma$. We also continue with lessons-learned in robustly analyzing these kind of high-precision JWST/MIRI 15 $\mu$m eclipse observations. Notably, we find that the Frame Normalized Principal Component Analysis (FN-PCA) method appears more robust against the choice of extraction aperture size, which otherwise can have a significant impact on the inferred eclipse depth and scientific conclusions when using a standard
polynomial baseline detrending method.
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All authors Nicholas J. Connors, Christopher Monaghan, Björn Benneke, Lisa Dang, Pierre-Alexis Roy
High Energy Physics (Theory)
Boundary criticality in the Gross-Neveu-Yukawa model at higher orders
Oleksandr Diatlyk, Simone Giombi and Zimo Sun
We extend the study of boundary criticality in the Gross-Neveu-Yukawa universality class beyond leading order. Using the
hyperbolic space formulation of boundary conformal field theories, we compute the first subleading corrections at large $N$ to the free energies of the “normal", “ordinary" and “special" boundary universality classes. We also determine the order $1/N$ correction to the dimension of the boundary
fermion at the normal fixed point. In the Gross-Neveu-Yukawa theory in $d=4-\epsilon$, we perform a higher-order analysis of the boundary free energy, and use it to extract estimates for the boundary central charge in $d=3$. The large $N$ and $\epsilon$-expansion results are shown to be precisely consistent in overlapping regimes, providing nontrivial consistency checks for the identification of the boundary universality classes. Our calculations rely on a combination of AdS harmonic analysis and boundary conformal field theory techniques.
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Superconductivity
Bulk Superconductivity driven by Disorder-Induced Delocalization in 4Hb-Ta(S$_{1-x}$Se$_x$)$_2$
Lu Chen, Sae-Hee Ryu, Avior Almoalem et al. (+10 more)
The unconventional
superconductor 4Hb-TaS$_2$ is a natural
heterostructure that can be broadly understood as interleaving Mott-like and metallic layers. We study the properties of this material as a function of quenched disorder in the form of Se/S substitution and find that while disordered samples show bulk superconductivity, clean samples do not. We show that a disorder-driven delocalization of carriers in the Mott-like ($1T$-) layer forms a new
Fermi surface that is absent in the cleanest samples. This suggests that one of the primary drivers for superconductivity is the fragility of the Mott state, whose delocalization brings to life a sea of strongly correlated electrons.
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All authors Lu Chen, Sae-Hee Ryu, Avior Almoalem, Yuanqi Lyu, Koh Yamakawa, Luke Pritchard Cairns, Ryan Day, Ehud Altman, Daniel Podolsky, Dung-Hai Lee, 4 Vidya Madhavan, Eli Rotenberg, James G. Analytis
High Energy Astrophysical Phenomena
Shing-Chi Leung, Seth Walther, Alexander Kusenko et al. (+2 more)
The asteroid-mass class of
Primordial Black Holes (PBHs) is one of the candidates for the dark matter in the universe. With a mass between $4 \times 10^{-17} < M_{\rm PBH} < 4 \times 10^{-12}~M_{\odot}$, they could be the major component of dark matter in the
cosmic mass budget. The infall of these PBH into a white
dwarf could be one triggering mechanism of Type Ia
supernovae (SNe Ia). In [Leung et al, ApJ 991, 11 (2025)] (Paper I), we studied the ignition, explosion dynamics, radiative transfer, and post-explosion nucleosynthesis of the PBH-triggered SNe Ia. The diversity of the explosion models can reconcile with the empirical Phillips relation. In this work, we developed the PBH-triggered SN Ia models in various
metallicity. We show that models from this channel can explain some recently observed SN Ia light curves and
supernova remnants. We further investigate how these
supernovae could affect the chemical
evolution on the
galactic scale by adding the new SN Ia models as a new chemical source. We examine how the observed chemical trends of
stars can lead to constraints on the fraction of this explosion channel relative to the canonical binary
star channel. Our models suggest that the PBH can be one major SN Ia channel in the early universe. We also include a comparative study to extract the effects of PBH-triggered SN Ia parameters on the actual chemical trends in the
galactic chemical
evolution model.
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All authors Shing-Chi Leung, Seth Walther, Alexander Kusenko, Ken'ichi Nomoto, Tomoharu Suzuki
High Energy Physics (Theory)
On the large N convergence of matrix models
M.P. Garcia del Moral, P. León and A. Restuccia
In this paper, the large N behavior of a supersymmetric
matrix model is compared with its exact continuum description. We concentrate on the large N limit of a supersymmetric
matrix model describing a supermembrane with central charge on a toroidally compactified target space. We analyze, on the one hand, the supermembrane model formulated on a differentiable compact
torus without boundary, with structure group given by the area-preserving diffeomorphisms, and, on the other hand, the associated regularized $SU(N)$ model. We emphasize in our analysis the structure of the constraints of the regularized model, which generate the $SU(N)$
algebra and reproduce the area-preserving diffeomorphism
algebra in the large N limit, together with the topological information associated with the central charge of the model. We explain the role of the central charge in the compactified supermembrane and how it allows a top-down $SU(N)$ regularization. It is known that the regularized model has discrete spectrum. We prove, in the semiclassical approximation of the models, that in the large N limit the
eigenvalues of the
Hamiltonian of the supersymmetric
matrix model are in one to one correspondence with, and converge exactly to, the
eigenvalues of the
Hamiltonian of the supermembrane (M2-brane) with central charge. Finally, we discuss some physical consequences of this result.
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Earth and Planetary Astrophysics
The Roasting Marshmallows Program with IGRINS on Gemini South V: Atmosphere of MASCARA-1b is Enriched in Refractory Elements
Krishna Kanumalla, Michael R. Line, Martina Chiarella et al. (+75 more)
Ultra-hot Jupiters (UHJs; $T_{\rm eq} \gtrsim 2000$ K) enable simultaneous detection of volatile (ice-forming) and refractory (rock-forming) species in planetary atmospheres, providing a powerful diagnostic of
planet formation and atmospheric processing. We present a comprehensive high-resolution cross-correlation spectroscopy (HRCCS) analysis of the UHJ MASCARA-1b ($T_{\rm eq} \approx 2600$ K) using the IGRINS and IGRINS-2 spectrographs. We detect robust (SNR$>$4) signals from H$_2$O, CO, OH, Fe I, Mg I, Ca I, and Ti I, marking the most complete atmospheric inventory of MASCARA-1b to date. Using a chemically consistent atmospheric inference framework, we constrain elemental abundances to a typical precision of $\approx$0.2 dex, retrieving a
solar atmospheric
metallicity ([M/H]$_\odot$ $= 0.07^{+0.17}_{-0.13}$ $\approx 1.2\times$
solar), a C/O ratio (C/O $= 0.65^{+0.08}_{-0.08}$) consistent with
solar value (C/O $=$ 0.59), an enhanced refractory abundance ([R/H]$_\odot$ $= 0.40^{+0.23}_{-0.17} \approx 2.5\times$
solar; $\approx 3.8\times$
stellar), and a moderately super-
solar refractory-to-volatile ratio ([R/V]$_\odot$ $= 0.36^{+0.11}_{-0.09}$ $\approx 2.3\times$
solar). Comparison with formation models suggests that MASCARA-1b most likely accreted material between the soot-H$_2$O or H$_2$O-CO snowlines (at 68$\%$ confidence). We additionally find
stellar values for atmospheric Ti/Mg and Ca/Mg ratios (at 68$\%$ confidence). The Mg/Fe is also found to be consistent with
stellar value at 95$\%$ confidence. Therefore, we do not find strong indication of nightside cold trapping in MASCARA-1b. As homogeneous refractory-to-volatile measurements expand across the UHJ population, particularly with upcoming Extremely Large
Telescopes, these diagnostics will enable statistically robust tests of emerging trends in
giant planet formation and atmospheric
evolution.
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All authors Krishna Kanumalla, Michael R. Line, Martina Chiarella, Matteo Brogi, Peter C. B. Smith, Jorge A. Sanchez, Yayaati Chachan, Joshua Lothringer, Joost P. Wardenier, Hayley Beltz, Carlos Saffe, Emily K. Deibert, Megan Weiner Mansfield, Stefan Pelletier, Vivien Parmentier, Yeon-ho Choi, Swaetha Ramkumar, Arjun B. Savel, Luis Welbanks, Jacob L. Bean, Vatsal Panwar, Tomás Azevedo Silva, Lorenzo Pino, Yuya Hayashi, Dongwook Lim, Cicero X. Lu, Venu M. Kalari, Teo Močnik, Mark G. Rawlings, Heeyoung Oh, Ruben J. Diaz, Chan Park, Jae-Joon Lee, Sanghyuk Kim, Ueejeong Jeong, Hye-In Lee, Woojin Park, Youngsam Yu, Yunjong Kim, Moo-Young Chun, Jae Sok Oh, Sungho Lee, Jeong-Gyun Jang, Bi-Ho Jang, Hyeon Cheol Seong, Hyun-Jeong Kim, Cynthia B. Brooks, Gregory N. Mace, Hanshin Lee, John M. Good, Daniel T. Jaffe, Kang-Min Kim, In-Soo Yuk, Narae Hwang, Byeong-Gon Park, Hwihyun Kim, Brian Chinn, Francisco Ramos, Pablo Prado, John White, Andres Olivares, Valentina Oyarzun, Emma Kurz, Hawi Stecher, Carlos Quiroz, Ignacio Arriagada, Thomas L. Hayward, Hyewon Suh, Jen Miller, Siyi Xu, Emanuele Paolo Farina, Charlie Figura, Andrew Stephens, Bryan Miller, Kathleen Labrie, Paul Hirst, Edo Tapia, Zachary Hartmann
Quantum Physics
Quantum correlations in QBism's reconstruction program
Sachin Gupta and Jacques Pienaar
QBism recasts
quantum theory as a normative framework for an
agent's probability assignments, with the Born rule taking the form of a consistency condition known as the Urgleichung. Motivated by this perspective, qplex theories provide a broader class of probabilistic models in which the sets of valid states and measurements are constrained by QBist-inspired
geometric conditions. While qplexes have been extensively studied for single systems, their implications for bipartite correlations remain largely unexplored. In this work, we investigate bipartite correlations in qplex theories by expressing joint expectation values as inner products between suitably defined $C$-vectors. This
geometric formulation allows Bell-type inequalities to be studied as optimization problems over qplex-compatible probability assignments. We first analyze the CHSH scenario and show that the shared inner-product structure of the $C$-vectors restricts the maximal value to the Tsirelson bound $2\sqrt{2}$. We then turn to the three-outcome CGLMP inequality $I_{2233}$ and find that the same qplex-derived norm and inner-product constraints allow a violation of up to $\leq 2+2\sqrt(3)/3 \approx 3.1547$ versus the
quantum maximum of $\approx 2.8729$, thereby exhibiting super-
quantum correlations. These results show that qplex geometry captures enough structure to reproduce an important
quantum bound in the two-outcome case, but not enough to recover the full set of
quantum correlation constraints. The analysis therefore suggests that additional principles are needed to complete the QBist reconstruction of
quantum theory.
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Earth and Planetary Astrophysics
A New Scaling Law for Non-Dipolar Magnetic Fields in Rapidly Rotating Stars and Planets
Paula N. Wulff, Hao Cao and Jonathan M. Aurnou
Magnetic field generation in
giant planets and rapidly rotating
stars produces a diverse range of field geometries, from large-scale dipole-dominated configurations to complex, small-scale multipolar structures. Earlier dynamo studies have suggested that multipolar solutions tend to arise when rotational effects become less dominant. We investigate the strength of non-dipolar
magnetic fields generated in systems dominated by rotation. 40 three-dimensional, spherical-shell dynamo simulations were carried out using the MagIC code, primarily made up of bistable pairs - simulations with the same control parameters that can settle in both a dipolar and non-dipolar steady-state regime. We use this suite of models to test how their
magnetic field strength scales with heat flux and velocity. Our dynamo simulations produce
magnetic fields with morphologies that fall on the two distinct branches, dipolar or non-dipolar, yet have very similar convective velocities. The strength of the dipole component differs by an order of magnitude between the two regimes, when scaled as a function of driving power. However, their non-dipolar
magnetic field strengths are very similar. We conclude that when attempting to predict the
magnetic field strength of rapidly rotating
planets and
stars, one cannot assume that it will have a dipole-dominated geometry. In particular, the amplitude of the dipole component is expected to be an order of magnitude smaller in the non-dipolar regime.
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Quantum Physics
Driving Exchange Interaction in Spin Qubits with Quasi-Zero Pulses
Julian D. Teske, Remy L. Delva, Shobhan Kulshreshtha et al. (+6 more)
The implementation of high-fidelity
quantum gates for
spin qubits requires accurate control of exchange interactions between electrons confined in
quantum dots, but pulse distortions can limit this control accuracy. Although linear-dynamical distortions can be compensated for by appropriately convolving the control signal, determining the necessary convolution requires detailed knowledge of the distortion's transfer function, and therefore the calibration of numerous parameters. Alternatively, control pulses can be designed to have a net-zero time integral canceling out linear-dynamical pulse distortions. We generalize net-zero pulse designs to quasi-zero pulses allowing net-positive but reduced time integrals. Using these pulse designs, we systematically develop complete gate sets for exchange-only
qubits, and study the resulting tradeoffs between pulse duration, fidelity, and the required number of tunable parameters, both in simulation and experiment. We
benchmark the optimized gate pulses on Intel's Tunnel Falls six-dot device and show they achieve fidelities similar to those obtained with a full filtering approach, with identical pulse durations and fewer tuning parameters. This reduction in complexity opens the door to fast and easily automated calibration schemes compatible with large-scale commercial
quantum devices.
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All authors Julian D. Teske, Remy L. Delva, Shobhan Kulshreshtha, Yuval Baum, Florian Luthi, Fahd A. Mohiyaddin, Rostyslav Savytskyy, Thomas Watson, Pranav S. Mundada
General Relativity and Quantum Cosmology
Stochastic scalar-tensor inflation and beyond
Yoann Launay
During cosmological inflation, inhomogeneities arising from
quantum vacuum fluctuations are stretched to become super-Hubble and effectively classical. As many scenarios of the origin involve nonlinearities or a breakdown of perturbativity in the infrared, the limitations of
quantum field theory can be addressed using a
stochastic description of the dynamics, the so-called
stochastic inflation paradigm. However, the
stochastic formalism was only recently formulated consistently within full General Relativity and has not yet been extended to more general theories of the early universe, which is the subject of this work. In order to find the
stochastic sources for a wide class of fully nonlinear scalar-tensor theories, we apply our gauge-agnostic coarse-graining procedure to the linear equations of the associated effective field theory. Each theory can then be mapped to its own set of
stochastic equations of motion by identifying the corresponding coefficients in the former. We illustrate this with a few concrete and, in most cases, unprecedented examples, including Gauss-Bonnet, generalized Brans-Dicke, Horndeski, and braiding theories. Finally, we discuss other natural extensions to provide a phenomenologically complete
stochastic framework. For example, we showcase the coarse-graining of multifield inflation in full General Relativity and argue for the generality of our procedure and thus its potential applications beyond the realm of inflation.
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