Astrophysics of Galaxies
Balmer Break Measurements Trace Departures from the Star-Forming Main Sequence at $1<z<4$ with JWST/NIRSpec
Suprabhas Narisetty, Yongda Zhu, Eiichi Egami et al. (+4 more)
We present JWST/NIRSpec PRISM observations of
galaxies at $1<z<4$ to study the relation between Balmer-break strength ($D_{\rm Balmer}$) and recent
star formation. Using NIRSpec spectra from the JADES Transient Survey in GOODS-S, we measure $D_{\rm Balmer}$ and hydrogen recombination-line equivalent widths, and infer
galaxy properties through spectral energy distribution (SED) fitting of the accompanying photometry. We find a clear anti-correlation between $D_{\rm Balmer}$ and the rest-frame equivalent width of H$\alpha$+[\ion{N}{2}], such that
galaxies with stronger breaks show weaker nebular emission and lower recent
star formation activity. $D_{\rm Balmer}$ also correlates with mass-weighted
stellar age, supporting its use as an empirical tracer of evolved
stellar populations at these
redshifts.
Star formation rates inferred from H$\alpha$, Pa$\gamma$, and SED fitting are broadly consistent, with scatter likely driven in part by
dust attenuation, line-measurement uncertainties, and the different timescales probed by each indicator.
Galaxies with stronger $D_{\rm Balmer}$ also tend to lie further below the
star-forming main sequence at fixed
stellar mass, indicating that $D_{\rm Balmer}$ is linked to recent suppression of
star formation. In contrast, we find only a weak relation between $D_{\rm Balmer}$ and SED-derived
dust attenuation, suggesting that
dust is not the main driver of the observed trends. These results show that $D_{\rm Balmer}$, combined with recombination-line measurements, is a useful empirical diagnostic of
galaxies transitioning away from the
star-forming population at
cosmic noon.
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All authors Suprabhas Narisetty, Yongda Zhu, Eiichi Egami, Stefano Carniani, Francesco D'Eugenio, Christa DeCoursey, Christopher N. A. Willmer
Astrophysics of Galaxies
MUSE spectroscopy of the compact dual AGN in the $z=3.273$ radio-loud gravitational lens MG B2016+112
Jianghao Huyan, Júlia M. Sisk-Reynés, Daniel A. Schwartz et al. (+4 more)
Dual active
galactic nuclei (AGN) are unique laboratories for studying how
galaxy mergers trigger
accretion onto supermassive black holes (SMBHs). However, at
redshifts $z>1$, only few dual AGN are confirmed at projected separations $\gtrsim$ 1 kpc for the two SMBHs. We present archival MUSE spectroscopy of the three resolved lensed images of the
radio-loud system MG B2016+112. At z = 3.273 and at a projected separation of 175 pc, this the most compact confirmed dual AGN at z > 1. We detect Ly$\alpha$, C IV, N V, He II, and C III] emission across images A$--$C after correcting for ISM absorption at $z \sim 0$. We find that the Ly $\alpha$, C IV, N V lines are affected by saturated absorption at $z \sim 3.27$. The He II / C III] emission-line ratios are consistent between images A and B but differ significantly from image C. We fit the C IV emission regions of images A$--$C by allowing for up to two Gaussians and use broad component to place lower limits on their respective SMBH masses: $\gtrsim 2 \times {10}^{7} M_\odot$, $\gtrsim 2.3 \times {10}^{7} M_\odot$, and $\gtrsim 1.5 \times {10}^{7} M_\odot$. Correcting for their strong
lensing magnifications suggests Eddington ratios of $\lesssim$ 0.47, 0.51, and 0.04, respectively. Together with previous VLBI and X-ray analyses, our results provide strong, independent spectroscopic evidence that MG B2016+112 hosts two AGN. Our findings motivate deep, spatially resolved near-IR spectroscopy to independently revisit our mass estimates and determine the physical conditions of the host
galaxy, which has likely undergone a major merger.
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All authors Jianghao Huyan, Júlia M. Sisk-Reynés, Daniel A. Schwartz, Varsha P. Kulkarni, Anna Barnacka, Adi Foord, Charlotte A. Eades
High Energy Physics (Theory)
Cardy random matrix theory
Marco Ambrosini, Alexandre Belin, Jan de Boer et al. (+1 more)
We construct and study a “Cardy random
matrix model”: a random
matrix theory whose only input, in a maximal-ignorance prescription, is the constraint of $\mathbb{S}$-modular invariance. We regularize this constraint by coarse-graining over energy windows of fixed width, and obtain a potential for a single random
matrix whose
eigenvalues play the role of the scaling dimensions of primaries in a 2d CFT. The potential drives the coarse-grained density of states to the Cardy profile above a gap at the black hole threshold. We perform Monte Carlo simulations to confirm this behavior and find good agreement for the coarse-grained density of states, while at the same time revealing GUE statistics for nearby
eigenvalues. We identify the scaling limit in which these phenomena emerge. In this limit, the model realizes a hierarchy of scales: at the macroscopic scale given by the window size, the occupations are frozen and the bootstrap constraint rigidly fixes the spectrum to the Cardy profile, while at the mesoscopic scale (inside a window) the Vandermonde repulsion rearranges the
eigenvalues as in a random
matrix theory. It is only at the microscopic scale of the mean level spacing that the individual levels are resolved. Accordingly, our random
matrix model displays an effective Thouless time, set by the inverse energy width of the coarse-graining window. Our model provides a first step towards solving the
matrix/tensor model dual to 3D
quantum gravity on a computer.
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All authors Marco Ambrosini, Alexandre Belin, Jan de Boer, Julian Sonner
Atomic Physics
Microwave Power-to-Frequency Transduction in a Magnetically Initiated Rydberg Dissipative Time Crystal
Darmindra Arumugam
Microwave power-to-frequency transduction is demonstrated using the emergent oscillation frequency of a magnetically initiated Rydberg dissipative time
crystal (DTC). In a room-temperature 87Rb vapor, a ~14 G
magnetic field establishes a self-sustained DTC near 21 kHz, while a near-resonant 8.325 GHz field coupling the 63D3/2 to 64P3/2
manifold continuously shifts the autonomous oscillation frequency. The resulting field-to-frequency transfer function is strongly nonlinear, with a total fundamental-frequency excursion of ~6.7 kHz and peak responsivity approaching 1 kHz/(mV/cm). The nonlinear transition is substantially steeper than a simple quadratic saturation response and is captured by a self-consistent mean-field picture in which microwave-driven Rydberg-population redistribution modifies the collective resonance condition. Higher DTC harmonics preserve the same normalized transfer function while exhibiting approximately linear growth of absolute responsivity with harmonic order. These results establish an intrinsic many-body atomic route to RF amplitude-to-frequency conversion, enabling continuous frequency-domain sensing through an emergent atomic frequency without an externally engineered RF feedback oscillator, repeated optical spectral scans, or resolved Autler Townes splitting.
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Solar and Stellar Astrophysics
Measuring the Expansion of Solar Magnetic Fields with Multiline Inversions from Sunrise III
Juan Carlos Trelles Arjona, María Jesús Martínez González, Christoph Kuckein et al. (+34 more)
Magnetic fields in the
solar atmosphere are expected to expand with height, forming
magnetic canopies that couple the photosphere and chromosphere. Except for sunspots, direct measurements of this expansion remain scarce because they require simultaneous
magnetic diagnostics over a broad range of atmospheric heights. We analyze four consecutive high-resolution spectropolarimetric raster scans of an emerging flux region observed with the Sunrise III/SCIP instrument. Simultaneous inversions of five photospheric Fe I lines and two chromospheric Ca II lines provide a quasi-continuous reconstruction of the
magnetic field from the deep photosphere to the lower chromosphere. We apply a constant-flux method that follows the same
magnetic flux through different atmospheric layers to quantify
magnetic expansion. All three pores analyzed exhibit an overall increase in
magnetic area with height, approximately doubling their cross section between the lower photosphere and the highest atmospheric layers sampled by the inversions. The expansion remains broadly stable throughout the 48-minute observing sequence. We further characterize the expansion with a quadratic parameterization and investigate its relation to pore properties. The three pores exhibit similar core
magnetic field strengths but different expansion behaviors, indicating that the
magnetic core strength alone does not determine the expansion. However, the present sample is too small to establish whether these differences are related to the thermodynamic or
magnetic properties of the pores and their surroundings. These results demonstrate the potential of simultaneous multiline inversions for investigating the three dimensional
magnetic topology of
solar magnetic structures and provide the first direct measurements of the height-dependent
magnetic expansion of
solar pores.
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All authors Juan Carlos Trelles Arjona, María Jesús Martínez González, Christoph Kuckein, Sergio Javier González Manrique, Manuel Collados, Sami K. Solanki, Andreas Lagg, Achim Gandorfer, Jose Carlos del Toro Iniesta, Yukio Katsukawa, Pietro Bernasconi, Thomas Berkefeld, Alex Feller, Tino L. Riethmüller, Alberto Álvarez-Herrero, Masahito Kubo, H. N. Smitha, David Orozco Suárez, Bianca Grauf, Michael Carpenter, Alexander Bell, Valentín Martínez Pillet, Francisco Javier Bailén, Julian Blanco Rodríguez, Juan Sebastián Castellanos Durán, Edvarda Harnes, Johannes Hölken, Francisco A. Iglesias, Ryohtaroh T. Ishikawa, Yusuke Kawabata, Takuma Matsumoto, Takayoshi Oba, Azaymi L. Siu-Tapia, Hanna Strecker, Dušan Vukadinović, Hirohisa Hara, Toshifumi Shimizu
High Energy Physics (Experiment) · Cross-listed from cs.SE
Hypothesis-awkward: Property-Based Testing Strategies for Awkward Array
Tai Sakuma, Ianna Osborne and Peter Elmer
Hypothesis-awkward is a collection of Hypothesis strategies for Awkward Array. Awkward Array can represent a wide variety of nested, variable-length, mixed-type data. Many tools that process Awkward Arrays are widely used and actively developed. The unit test cases of many of these tools list predefined input samples. In practice, such samples can cover only a small portion of the vast combinatorial space of Awkward Array instances. Hypothesis, a Python property-based testing library, generates test data that can make test cases fail and automatically explores edge cases. The main strategy of Hypothesis-awkward generates nearly all possible Awkward Arrays, with options to control the layout, data types, missing values, masks, and other array attributes. Property-based tests written with these strategies have begun to run in the continuous integration of Awkward Array; to date, they cover a small part of Awkward Array and have found 37 bugs in it, as well as one in Hypothesis itself. These strategies make the tests of Awkward Array and of the tools that use it more reliable.
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Nuclear Theory
Global equilibrium at order $\mathcal{O}(\hbar^2)$: pseudo-gauge ambiguity, Maxwell relations, and thermodynamic consistency
Asaad Daher, David Wagner, Masoud Shokri et al. (+1 more)
We study massive
spin-$1/2$ Boltzmann particles in global thermodynamic
equilibrium with rotation and acceleration, consistently including
quantum corrections up to order $\mathcal{O}(\hbar^2)$. For such a system, the fluid velocity becomes an independent thermodynamic variable and fundamental thermodynamic relations have to be extended. Employing the Wigner-function formalism, we show that the standard mass-shell condition $k^2 = m^2$ is modified at order $\mathcal{O}(\hbar^2)$ by contributions quadratic in the thermal vorticity. Incorporating this modified mass-shell constraint, we derive the (net) particle-number current, energy-momentum tensor,
spin-current tensor, and associated thermodynamic quantities in the kinetic, canonical, and de Groot–van Leeuwen–van Weert (GLW) pseudo-gauges. We explicitly demonstrate that, while global quantities, like the total particle number or total energy, are independent of the choice of pseudo-gauge, local quantities, like the particle-number density or the energy density, are pseudo-gauge dependent. We then examine the thermodynamic relations in each pseudo-gauge and demonstrate that thermodynamic consistency requires that the thermodynamic Maxwell relations are satisfied. We find that these relations hold in the kinetic-theory pseudo-gauge, whereas they are in general violated in the canonical and GLW pseudo-gauges. These findings suggest a preference for using the kinetic-theory pseudo-gauge in applications such as
spin hydrodynamics.
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All authors Asaad Daher, David Wagner, Masoud Shokri, Dirk H. Rischke
Physics and Society
Vertices that belong to every minimum dominating set of a graph and their connection with transportation sharing systems with study cases in Campo de Gibraltar area
Mohammad Farhan, Dorota Kuziak, Iztok Peterin et al. (+1 more)
This study addresses a theoretical model regarding equity and accessibility challenges in designing shared transportation systems (such as micro-mobility networks) by applying graph-vertex domination setting. The work focuses on identifying dominating forced vertices, that represent nodes belonging to every dominating set of a graph of the smallest possible cardinality, and which correspond to critical, non-negotiable station locations essential for maintaining system efficiency and coverage. From a theoretical perspective, in the paper it is first demonstrated that determining whether a given vertex is a dominating forced vertex is co-NP-hard, establishing the computational infeasibility of exact identification in large networks. To analyze graph structures, sharp theoretical bounds on the maximum number of dominating forced vertices are established, proving that their count is bounded above by one-third of the order of the graph, and provide complete structural characterizations for graphs achieving this bound, as well as, trees with no dominating forced vertices. To overcome computational limits in practical urban settings, the study uses an iterated greedy metaheuristic framework to generate minimal dominating sets and approximate critical forced nodes based on their appearance frequency across iterations. The methodology is validated on strong grid graphs and applied to real-world road network models of Algeciras and La Línea de la Concepción, two cities in the area of Campo de Gibraltar, Spain, which successfully pinpoints candidate location points for scooter-sharing stations across both cities.
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All authors Mohammad Farhan, Dorota Kuziak, Iztok Peterin, Ismael G. Yero
History and Philosophy of Physics
Does a Second-Class Primary Constraint Generate a Gauge Transformation? Electromagnetisms and Gravities, Massless and Massive
J. Brian Pitts
In constrained
Hamiltonian dynamics there are two views regarding how first-class constraints generate gauge transformations: individually or only in a certain combination, the Rosenfeld-Anderson-Bergmann-Castellani gauge generator. This gauge generator $G$ preserves Hamilton's equations and changes the canonical action at most by a boundary term;
Hamiltonian's equations are the Euler-Lagrange equations for the canonical action. Hence the canonical formalism is equivalent to the Lagrangian formalism, and indeed subsumed within it (in important examples) with many canonical momenta serving as auxiliary fields. $G$ generates transformations basically equivalent to the usual 4-dimensional Lagrangian expressions, such as a 4-gradient in electromagnetism or a space-time coordinate transformation (on-shell) in General Relativity. It has been shown recently that separate first-class constraints lead to inequivalent observables between Proca non-gauge and Stueckelberg gauge massive electromagnetism. There is, however, widespread agreement that second-class constraints do not generate gauge transformations. Here it is shown that in such a sense as the first-class primary constraint in Maxwell's theory generates a gauge transformation, the second-class primary constraint in Proca's massive electromagnetism also generates a gauge transformation. Likewise the second-class primary constraints in various massive
spin $2$ relatives of General Relativity generate as much of a gauge transformation as do the corresponding first-class primary constraints in GR. Hence the view that first-class constraints typically generate gauge transformations _individually_ faces a puzzle not faced by the gauge generator view.
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Space Physics
Electric Potential Patterns Forecasting in the Southern Hemisphere with Deep Learning Techniques
Francesco Pio Ramunno, Simone Mestici, Igino Coco et al. (+5 more)
Space weather disturbances driven by the
solar wind can degrade satellite
navigation, disrupt
radio communications, and threaten power infrastructure, making accurate
forecasting of the high-latitude ionosphere's response a critical operational need. Existing approaches, empirical climatological models and physics-based magnetohydrodynamic simulations, either smooth out the ionosphere's time-dependent, non-linear response or are too computationally expensive for real-time use, while prior machine learning efforts have mostly targeted scalar indices rather than the full spatial structure of ionospheric convection. Here we train and compare three deep learning architectures, a probabilistic
diffusion model conditioned on multi-variate
solar wind and interplanetary
magnetic field measurements at the L1 Lagrange point, an unconditioned
diffusion ablation, and a deterministic U-Net baseline, to forecast Southern Hemisphere high-latitude electric potential maps derived from SuperDARN radar observations. Using five years (2020–2025) of SuperDARN data synchronised with DSCOVR L1 measurements, we evaluate the models under a single-pass regime, an extended autoregressive rollout of up to 350 frames, and an out-of-distribution case study on the intense March 2015 St.\ Patrick's Day storm, unseen during training. We find that the relative advantage of the deterministic and probabilistic approaches is not fixed: the deterministic model is competitive over short horizons and calm conditions, while the
diffusion model's advantage grows and eventually dominates as the forecast horizon lengthens and the event becomes more dynamic, evidence that probabilistic, sample-based generative models are the more promising direction for operational, long-horizon space weather
forecasting.
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All authors Francesco Pio Ramunno, Simone Mestici, Igino Coco, Maria Walach, Stefano Massetti, Maria Federica Marcucci, Brandon Panos, André Csillaghy
General Relativity and Quantum Cosmology
Cosmological Dynamics and Observational Constraints of a Logarithmic Herglotz $f(R,T)$ Gravity
Vishal M C and Sankarsan Tarai
We investigate the cosmological dynamics and observational viability of a logarithmic Herglotz-type $f(R,T)$
gravity model described by $f(R,T)=R+\beta\ln(-T/T_0)$. Assuming a spatially flat Friedmann–Lemaître–Robertson–Walker background and pressureless matter, the modified field equations are formulated as a coupled dynamical system involving the Herglotz field and the normalized matter density. A phenomenological closure relation is adopted for the effective Herglotz sector, allowing the background
evolution to be determined numerically. The model is constrained using
Cosmic Chronometer measurements, the DESI DR2
baryon acoustic oscillation compilation, and the Union3
supernova sample, considering both individual and combined
datasets within a
Bayesian Markov-chain Monte Carlo framework. The combined analysis provides a statistically consistent description of the background expansion. The reconstructed expansion history yields a present-day effective equation of state $w_{\rm eff,0}\simeq-0.702$ and exhibits the expected transition from accelerated expansion at late times toward decelerated expansion at higher
redshifts. We further investigate the $Om(z)$ diagnostic and statefinder parameter. These results indicate that the logarithmic Herglotz model provides a consistent phenomenological description of the homogeneous and isotropic late-time expansion history, while allowing departures from the standard $\Lambda$CDM background.
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General Relativity and Quantum Cosmology
Chaos bound for spinning particles in a hairy black hole with two photon spheres
Chuanhong Gao
In this work, we investigate the unstable circular orbits of spinning test particles and the associated classical orbital chaos bound in a hairy black hole spacetime admitting a double
photon sphere structure. This background supports two distinct branches of unstable circular orbits, referred to as the inner and outer branches. We find that, within the parameter ranges considered, the inner branch always satisfies the chaos bound, whereas violations can occur on the outer branch. This behavior contrasts with many previous studies focusing primarily on near-horizon violations of the chaos bound and reveals a clear dependence of the bound on the orbital branch. Our analysis further shows that the total angular momentum of the particle has a pronounced effect on the local orbital instability and can enlarge the bound-violating region on the outer branch. Meanwhile, the deformation parameter of the background geometry regulates the validity of the bound by modifying both the orbital Lyapunov exponent and the black hole surface
gravity. By contrast, the effect of the particle
spin is comparatively weak and mainly shifts the existing unstable circular orbits and the corresponding critical boundaries through the
spin-
curvature coupling.
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Materials Science · Cross-listed from cs.AI
CP-Agent: A Harness-Engineered Agent for Crystal Plasticity Simulation Workflows
Samuel Onimpa Alfred, Abhishek Kumar and Veera Sundararaghavan
Crystal plasticity (CP) simulations predict the mechanical behavior of polycrystalline metals, yet their routine use is hindered by the manual effort of configuring heterogeneous tools, orchestrating multi-step data pipelines, and calibrating constitutive parameters against experiments. These bottlenecks impede productivity in systematic parameter studies, motivating interest in automated workflows. This study presents CP-
Agent, a harness-engineered LLM-based
agent that autonomously executes complete CP modeling workflows from natural-
language tasks. Operating under the ReAct paradigm, the
agent reasons about tool selection and sequencing while delegating numerical search to established optimizers. The harness comprises a minimal system
prompt, typed tool definitions, a dispatcher, and a safety-bounded iteration loop, encoding domain knowledge through tool schemas rather than hard-coded logic. CP-
Agent is demonstrated on four case studies: calibrating four slip parameters of additively manufactured stainless steel 316L against tensile data; validating the workflow against published copper
benchmarks, reproducing stress-strain and texture
evolution; recovering the initial crystallographic texture of copper, where the
agent correctly identifies a diffuse initial texture; and reproducing the multi-pass rolling texture
evolution of a Mg-Zn-Ca
alloy, where the
agent chains five deformation passes and recovers the experimentally observed weakened, split basal texture. In all cases, the
agent inferred the correct execution sequence from the task statement, robustly across repeated runs, and delivered physically interpretable results. This work establishes harness engineering as a systematic approach to automating CP modeling workflows while maintaining physical interpretability and auditability through visible
reasoning traces.
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Strongly Correlated Electrons
Quantum Representation Selects Neutral Skyrmion Molecules
Vishnu Jejjala
Skyrmions experience a sideways gyroscopic force when they move. Bound molecules can cancel this force; we call them gyroscopically neutral. We show that the
quantum states available on each site of a magnet select the composition needed for cancellation. In two models of $SU(3)$ magnetism, this composition changes from a pair to a trimer. Both models assign exactly the same energy to every configuration of their common classical order parameter, isolating the effect of the local
quantum states. Neutral molecules can also unwind when additional local states are allowed. Mean field calculations nevertheless find both compositions bound and locally stable, with the neutral trimer surviving sampled interaction changes. Comparing their motion reveals the changed cancellation rule, and prepared neutral molecules translate over short distances with little deformation.
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Strongly Correlated Electrons
A Unified Spin-Fermion Framework for Magnetic Diversity in Chromium Monopnictides
Ruoshi Jiang and Bartomeu Monserrat
Isoelectronic compounds are generally expected to exhibit related electronic, structural, and
magnetic behavior. Chromium monopnictides CrX (X= Sb, As, P), however, display a striking
evolution from high-temperature altermagnetism in NiAs-type CrSb, through double-helical antiferromagnetism in MnP-type CrAs, to the absence of resolved long-range
magnetic order in MnP-type CrP. Here, combining first-principles calculations in the non-collinear Curie-paramagnetic state, structural analysis,
magnetic phase-diagram calculations, and exchange-parameter extraction, we establish a unified microscopic framework for this
evolution. All three compounds share a formal high-
spin $d^5$ configuration, nominally Cr$^{1+}$, coupled to itinerant states of predominantly pnictogen character. From Sb to P, chemical pressure enhances ligand itinerancy and drives the structural
evolution from the high-
symmetry NiAs
lattice to increasingly distorted MnP-type networks. The accompanying reconstruction of competing Cr-Cr exchanges favors A-type antiferromagnetism in CrSb and double-helical order in CrAs, while placing CrP near a frustrated regime with closely competing
magnetic tendencies. Our results establish chemical-pressure-driven exchange reconstruction as a general mechanism through which a common
spin-
fermion electronic structure can generate contrasting
magnetic phases in strongly correlated materials.
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High Energy Astrophysical Phenomena
A Multidimensional General-Relativistic Boltzmann Solver for Neutrino Transport: Implementation, Discretization and Optimization
Arthur Offermans, Harry Ho-Yin Ng, Patrick Chi-Kit Cheong et al. (+2 more)
We present the implementation of a multidimensional general-relativistic Boltzmann solver for
neutrino transport using the finite volume method. We extend the general-relativistic magnetohydrodynamics solver Gmunu to discretize the full $6$D phase space. We discretize the momentum space in spherical coordinates in the comoving frame, and the position space in the lab frame in Cartesian, cylindrical or spherical coordinates. As in the M1 scheme, we expand the interaction kernels up to first order in a Legendre series. We present a discretization scheme that ensures consistency between the number-conservative and non-conservative formulations in empty flat spacetime, multiple dimensions and coordinate systems, conserves energy to $\sim 1\%$ with $20$ energy bins in 1D tests. We discuss optimizations of the implicit solver for stiff source terms to minimize its computational cost. In particular, we introduce a method that leverages the Legendre expansion of the kernels to reduce the dimensionality of the problem. In a 1D core-collapse
supernova snapshot, our method yields a speed-up factor of $300$ compared to a full-
matrix LU method for $14$ angular bins when including energy- and species-coupling interactions. Finally, we validate our implementation on standard test cases and report quadratic convergence in space, energy and propagation angles. We compare our solver to the M1 scheme in simplified 1D configurations and find differences of about $10\%$ in the free-streaming luminosities in relaxation test cases, which we attribute primarily to the M1 closure relation. The average energies, on the other hand, agree between the two methods. We compare both methods on a core-collapse
supernova test case and find an overall good agreement in the fluid variables' profiles at the time of core bounce for $20$ energy bins.
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All authors Arthur Offermans, Harry Ho-Yin Ng, Patrick Chi-Kit Cheong, Anthony Mezzacappa, Tjonnie Guang Feng Li
Quantum Physics
Exact series formulas for the capacities of the amplitude damping channel
Stefano Pirandola
We derive explicit, absolutely convergent series formulas for the
quantum, unassisted classical, and
entanglement-assisted classical capacities of the
qubit amplitude damping channel, eliminating residual optimizations and implicit roots. We also obtain analytical upper and lower bounds on two-way assisted
quantum and private communication capacities by evaluating a balanced-squashing bound and optimizing the reverse coherent information. Our results characterize the optimal input populations, establish convergence and truncation properties, and provide analytical
benchmarks for
quantum and classical communication over dissipative channels.
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Quantum Physics
Measurement-Based Uncomputation from an Error Correction Perspective
Minjun Jeon, Po-Wei Huang and Zhenyu Cai
Coherent uncomputation can be as costly as the computation itself, creating substantial spacetime overheads that can be prohibitive on early fault-tolerant
quantum computers. We develop an algebraic framework for measurement-based uncomputation (MBU) through a
quantum error-correction picture: measurements of the garbage register induce relative phases analogous to errors causing non-trivial syndromes. Accepting only zero-syndrome outcomes achieves post-selected MBU, removing the need for an uncomputation oracle at the cost of a probabilistic success rate determined by the affine rank of the populated garbage support. This rank can be much smaller than the number of garbage
qubits, as illustrated through an example of the HHL
algorithm. We then derive a structural condition under which the original uncomputation oracle can be reused to correct the phase for all measurement outcomes. No correction is required for the zero syndrome, while corrections for non-zero syndromes can be further adapted to individual measurement outcomes for simpler
circuits, as illustrated by existing modular-arithmetic, QROM, and QRAM MBU constructions. Phase-correction
circuits can be further simplified by co-optimising their implementation with the representation of the measurement-induced phases. Selecting which syndrome classes to correct interpolates between post-selected, partially corrected, and deterministic MBU, enabling trade-offs among correction cost, workspace, and repetitions.
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Quantum Physics
Exact Characterization of the Holevo Bound by a Quantum Fisher Information Family
Koji Yamaguchi and Hiroyasu Tajima
The
quantum Cramér-Rao bound constrains the precision of parameter estimation through the symmetric logarithmic derivative
quantum Fisher information (SLD QFI). It is asymptotically achievable for regular single-parameter estimation models, but generally not in the multiparameter setting, where optimal measurements for different parameters may be incompatible. For multiparameter estimation, allowing collective measurements, the corresponding asymptotically achievable precision limit is the Holevo bound, whose standard formulation is an optimization over auxiliary Hermitian operators. We bridge this apparent difference in formulation by giving an exact characterization of the Holevo bound in terms of a family of QFIs interpolating between the SLD and right logarithmic derivative (RLD) QFIs. Specifically, for any locally identifiable finite-dimensional estimation problem, we prove that the operator-feasible region in the standard variational definition of the Holevo bound coincides with the intersection of the regions defined by the corresponding Cramér-Rao-type
matrix constraints for the entire QFI family. This characterization also applies to rank-deficient states and does not require any prior choice of weight
matrix. Consequently, the conventional weight-dependent Holevo bound is recovered by minimizing the corresponding weighted cost over the resulting common feasible region.
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Quantum Physics
Scalable Hybrid Device Architecture on Thin-Film Lithium Tantalate for Long Distance Quantum Network Nodes with Atomic Frequency Comb Quantum Memories
Ayed Sayem and Towsif Taher
Scalable photonic
circuits are essential for realizing practical
quantum networks beyond proof-of-principle demonstrations. Although diamond-based integrated photonics has been extensively investigated over the past two decades for
quantum networking applications, its integration into scalable photonic platforms remains challenging.
Quantum memories based on rare-earth-ion atomic frequency combs (AFCs) offer an attractive alternative; however, most demonstrations to date have relied on bulk free-space
crystals, limiting their scalability for practical implementations. In this work, we systematically investigate the potential for hybrid integration of AFC-based
quantum memories with a scalable integrated photonic platform. We propose a device architecture combining thin-film lithium tantalate (TFLT) nanophotonic
circuits with ytterbium-doped yttrium orthosilicate (Yb:YSO)
crystals for long-distance
quantum communication. Our analysis shows that the hybrid TFLT-YSO platform offers a promising and scalable pathway toward integrated
quantum memories and, ultimately, large-scale
quantum networks.
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Quantum Physics
Ruohan Shen and Soonwon Choi
Learning and sensing are among the most promising applications of
quantum technology, often with provable
quantum advantages. In any realistic experiment, however, noise threatens to erase these advantages as the problem size grows. We introduce oracle
distillation, a procedure that distills many queries to a noisy oracle into a single high-fidelity oracle. Here the oracle, an unknown
unitary from a known family, models the interface through which a
quantum device learns about an unknown system. We construct an explicit protocol that distills any Boolean oracle, both under
adversarial noise that corrupts a constant fraction of the input
qubits and under i.i.d. depolarizing noise at a constant rate on every
qubit. At the heart of the protocol is the weak query, in which the device deliberately queries the oracle only weakly, trading response strength for the ability to correct errors. Our protocol is near-optimal among all protocols that distill the oracle while keeping its errors correctable, revealing a fundamental tension between these two requirements. An important implication of the protocol is a threshold
theorem: every Boolean oracle problem whose
quantum advantage is
polynomial in the domain size, including Grover search, $k$-forrelation, and Simon's problem, retains a
quantum advantage whenever the per-
qubit depolarizing rate is below a constant threshold. In particular, the quadratic
quantum advantage of Grover search, long believed fragile under noise, survives nearly intact at low error rates even when almost every query involves errors on one or more
qubits. We further extend the protocol to fractional and continuous-time Boolean oracles.
Quantum error correction can thus protect not only prescribed operations but also unknown dynamics. Our results make a large family of
quantum advantages in learning robust against noise and open a path toward robust computational sensing.
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Instrumentation and Detectors
Transition Radiation Detector Upgrade for the GlueX-III Charmonium Program
Lauren Kasper, Alexander Austregesilo, Cody Dickover et al. (+9 more)
The GlueX-III experiment at Jefferson Lab, planned to run in 2027-2029, will enhance the laboratory's capability to explore charmonium production near threshold and related aspects of QCD in the non-perturbative regime. A central upgrade for GlueX-III is a large-scale triple-GEM Transition Radiation Detector (TRD) optimized for electron identification and pion suppression in the
hadron-rich environment of fixed-target photoproduction. This document describes the motivation for and efforts related to such an upgrade, including the design, construction, and performance of a 720x528mm$^{2}$ triple-GEM-TRD prototype that was tested in the existing GlueX-II experimental acceptance during the 2025 run. Results validate the prototype's integration, timing performance, and electron identification capability. Its projected impact in the GlueX-III setting is discussed, with background reduction in a $J/\psi$ candidate sample demonstrated. The development and use of a modern TRD technology in a high-background environment at Jefferson Lab may inform detector design choices as a future upgrade path for the EIC.
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All authors Lauren Kasper, Alexander Austregesilo, Cody Dickover, Sean Dobbs, Sergey Furletov, Yulia Furletova, Ilya Larin, Lubomir Pentchev, Saheli Rakshit, Nizar Septian, Simon Taylor, Julia Velkovska
Medical Physics
Numerical Simulation of Electrical Properties in Cortical and Trabecular Bone: A Simplified Model
María José Cervantes, Catalina A. Cely-Ortíz, C. Manuel Carlevaro et al. (+1 more)
The electrical properties of biological tissues depend on their composition and microstructure and determine their response to applied electric fields. In bone tissue, these properties are closely related to its composition, porosity, and microstructural organization. However, simplified models that link bone microstructure (trabecular and cortical) to its effective electrical properties while accounting for the electrical anisotropy of cortical bone remain scarce. In this work, a multiscale approach was developed, combining finite element simulations with Bruggeman-based homogenization models. Trabecular bone was modeled using microCT derived geometries, and its effective conductivity was analyzed as a function of BV/TV and free water content. Cortical bone was represented by a simplified three-dimensional network of Haversian canals (axial = z) and Volkmann canals (transverse), incorporating their directional organization through an anisotropic Bruggeman formulation. The models captured the conductivity range reported experimentally for trabecular bone (approximately 25-200 mS/m) and reproduced the anisotropic behavior observed in the cortical FEM simulations, with higher conductivity in the axial direction. In the generated cortical geometries, 65.5% of the total porosity was associated with axial Haversian canals. At the macroscale, the tibia model with lower trabecular and cortical BV/TV and reduced cortical thickness showed an approximately 38-39% reduction in impedance relative to the reference model. These results indicate that microstructural variations in bone tissue are reflected in its effective electrical properties and in the macroscopic impedance of the model, providing a physical and computational basis for future investigations into the sensitivity of electrical measurements to changes in bone microstructure.
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All authors María José Cervantes, Catalina A. Cely-Ortíz, C. Manuel Carlevaro, Ramiro M. Irastorza
Optics
A unified sensitivity kernel for coherent wave tomography in radar, seismic, ultrasound, and optical imaging
Alexey Yamilov
Imaging an inhomogeneous medium with waves rests on the response of a boundary measurement to a change of the medium inside, formally the sensitivity kernel of the inverse problem. Here we show that the kernels of radar, seismology, medical ultrasound, and diffuse optics all reduce to just two classes. Every kernel is the product of a forward and an adjoint field, and a real measurement retains one quadrature of that product. These quadratures are the two classes, selected either by a component of the material parameter or by the misfit, the structure that persists for the coherent-wave kernel in both the ballistic and the diffusive regime. We place these areas on one diagram of scattering strength and transport depth, exposing a shared computational limit set by wavefield storage, and propose a broadband on-shell compression that can relax that limit.
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Mesoscale and Nanoscale Physics
Emergent frustrated magnetism in strain-patterned graphene
Yu-Chiang Hsieh, Wen-Han Kao, Christophe De Beule et al. (+18 more)
Geometrically frustrated magnetism conventionally arises from pre-existing
magnetic moments on
lattices whose geometry prevents their interactions from being simultaneously satisfied, giving rise to highly degenerate states and rich collective behavior. Creating such frustration in an intrinsically non-
magnetic material presents a fundamentally different challenge, requiring both the magnetism and the competing interactions to emerge from correlated electrons. Here we show that this can be realized in
graphene through lithographically programmable strain engineering. Patterning strain and the associated pseudo-
magnetic field (PMF) into superlattices creates a correlated electronic system with flat bands and strong interactions. Transport measurements reveal interaction-driven insulating behavior, anisotropic
magnetic hysteresis, and slow relaxation dynamics reminiscent of
spin freezing, qualitatively captured by Monte Carlo simulations of competing
magnetic moments on the PMF-defined ruby superlattice. Cryogenic
magnetic force microscopy further reveals
magnetic textures associated with the PMF landscape. These observations demonstrate frustrated magnetism emerging from correlated electrons in otherwise non-
magnetic graphene. Our results establish lithographic strain engineering as a general and scalable route to flat bands and correlated states in van der Waals materials, providing a versatile platform for programmable
quantum matter.
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All authors Yu-Chiang Hsieh, Wen-Han Kao, Christophe De Beule, Sheng-Zhu Ho, Ru-Long Gou, Bo-Nian Chen, Kuan-Yu Chou, Kuo-En Chang, Chin-Chia Chang, Ying-Mei Yang, Ching-Hua Kao, Hao-Chien Chiang, Jyun-Lin Chen, Sheng-Chin Ho, Kenji Watanabe, Takashi Taniguchi, Ming-Hao Liu, Ching-Hao Chang, Yi-Chun Chen, Ying-Jer Kao, Tse-Ming Chen
Earth and Planetary Astrophysics
Inclination of Miranda as a Constraint on the Tidal Dissipation of Uranus
Maryame El Moutamid and Matija Ćuk
The five major moons of Uranus record a complicated geological history characterized by both tectonic resurfacing and heavy impact cratering, connecting their
evolution to dynamical processes in the
Solar System. Miranda, the smallest and closest major moon to Uranus, has an unusually large orbital inclination ($4.3^\circ$) and an remarkable surface geology dominated by coronae and tectonic structures. In this paper we explore whether Miranda's inclination and geological history can be explained through past orbital resonances within the Uranian satellite system. Using direct $N$-body integrations with the code SIMPL, we explore the
tidal and dynamical
evolution of the five major moons while assuming a fast
tidal dissipation of Uranus and varying the internal responses of the satellites. Our simulations confirm that Miranda's inclination can be excited through resonant interactions involving Ariel and Umbriel, even when Miranda mean motion is not involved in that resonance. The Ariel-Umbriel 5:3 mean-motion resonance appears to be the most recent major dynamical event capable of driving Miranda's inclination to its current value. We compute the
tidal heating associated with these resonance encounters and show that, for a strongly dissipative Uranus ($Q_U\sim600$), the resonance could cause heat fluxes in Miranda approaching those required to form its coronae. These results could provide new constraints on Uranus's
tidal dissipation.
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High Energy Physics (Theory)
Bootstrapping Holographic Theories in the Planar Limit
Shai M. Chester, Daniele R. Pavarini and Alessandro Piazza
We combine the numerical conformal bootstrap with supersymmetric localization to constrain the spectrum of
holographic superconformal field theories in the planar large $N$ limit for finite 't Hooft coupling $\lambda$. We consider the stress tensor multiplet four-point function in $\mathcal{N}=4$ $SU(N)$ super-Yang-Mills (SYM), which is holographically dual to closed string scattering, as well as the
flavor multiplet correlator in a certain $ 4d $ $\mathcal{N}=2$ $U\!Sp(2N)$ gauge theory with $SO(8)$
flavor symmetry, which is dual to open string scattering. In both cases, we combine dispersive sum rules with integrated constraints from supersymmetric localization to compute an upper bound on the scaling dimension of the lowest scalar single-trace operator for all $\lambda$. For $\mathcal{N}=4$ SYM, we find that our bounds are close to the known integrability result for all $\lambda$. For the $\mathcal{N}=2$ theory, where integrability is not yet available, we find that our bounds are close to weak and strong coupling predictions in the relevant regimes.
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Solar and Stellar Astrophysics
A Comprehensive Study of the Magnetic White Dwarfs in DESI DR1
Adam Moss, Pierre Bergeron, Mukremin Kilic et al. (+2 more)
As the end point of
stellar evolution for most
stars, white
dwarfs offer powerful insight into
stellar magnetism. Multiple formation channels are required to explain the observed properties of
magnetic white
dwarfs, and the mechanisms that produce unusual objects have potential to unlock new realms of physics. The large samples made possible by spectroscopic surveys enable study of these processes on an unprecedented level. Here we perform a detailed model atmosphere analysis of the
magnetic white
dwarfs in DESI Data Release 1. We identify 833
magnetic systems, 762 of which we fit using an offset dipole model. Of these, 127 targets require more in-depth analysis as they possess shallower or sharper absorption features than predicted by the offset dipole model. For these we use a patchy offset dipole atmosphere model in which the
magnetic field only contributes to the line opacities at certain regions of the visible
stellar disk. We compare the observed distribution of
magnetic white
dwarfs to the mechanisms that generate
magnetic fields. We find that a core-convective dynamo that forms on the main-sequence matches the parameters of many of the
magnetic systems, while a dynamo that fills the radiative interior on the
giant branch reproduces many of the lower mass objects that the core-convective dynamo cannot. This sample is the largest single data release of
magnetic white
dwarfs to date. The diversity of formation channels and the frequency of objects with unusual field geometries highlight the power of multiplexed surveys to advance our knowledge of
stellar magnetism.
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All authors Adam Moss, Pierre Bergeron, Mukremin Kilic, Warren R. Brown, Jamie Tayar
Quantum Physics
Exact Solutions of the Dunkl–Pauli Equation in the Presence of a Magnetic Field from an su(1,1) Algebraic Approach
M.Salazar Ramírez, B. C. Lütfüoğlu and H. Bouguerne
We investigate the two-dimensional Dunkl–Pauli equation for a
spin–$1/2$ particle in the presence of an external
magnetic field within an algebraic framework. While previous studies have provided exact solutions of the Dunkl–Pauli system, its underlying dynamical
symmetry and algebraic structure remain largely unexplored. By employing Schrödinger factorization, we construct the generators of the $\mathfrak{su}(1,1)$
algebra and establish the associated
symmetry of the radial sector. The energy spectrum is derived using irreducible
unitary representations, and the corresponding Sturmian radial basis is obtained analytically. Furthermore, $\mathrm{SU}(1,1)$ coherent states are constructed and their time
evolution is analyzed, revealing a characteristic radial breathing behavior. The results show that the Dunkl deformation introduces parity-dependent modifications in the spatial structure of the system while preserving its underlying algebraic dynamics.
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General Relativity and Quantum Cosmology
Mind the second gap: The impact of gaps on noise and signal parameter inference
Ollie Burke, Federico Pozzoli, Martina Muratore et al. (+1 more)
Gravitational-wave data is never analysed without some conditioning: filtering and tapering act multiplicatively on the noise, destroying the stationarity on which the Whittle likelihood — the backbone of nearly all gravitational-wave inference — rests. The problem is particularly evident for LISA, where gaps are expected to overlap almost all signals and the noise must be estimated jointly with those astrophysical signals. We provide an analytical and numerical framework to assess the impact of noise mis-modelling when signal and noise parameters are inferred jointly in the presence of gaps. From a Fisher-
matrix formalism verified against
Bayesian inference, we obtain closed forms for the model uncertainties, their maximum-likelihood estimates and the true scatter in the latter, for various approximations to the likelihood. The Fisher-based linear formalism is extended through the Godambe–White
curvature to the non-linear regime that severe mis-modelling produces. We survey gap families from long, well-tapered interruptions to short, high-rate ones, injecting massive black-hole binaries. Except in the case of frequent gaps, we show that the windowed covariance is well approximated by its leading diagonal — the window convolved with the power spectral density — for the estimation of both signal and noise parameters. By omitting the convolution, the signal sector remains unbiased but the noise parameters, in particular the optical-metrology noise which is dominant at high frequency, is displaced by over an order of magnitude in power. At the highest glitch rates the diagonal approximation stays accurate yet loses an order of magnitude in precision. To remedy this, we propose an exact time-domain likelihood of the surviving samples which can be efficiently (and accurately solved) via preconditioned conjugate gradient methods.
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All authors Ollie Burke, Federico Pozzoli, Martina Muratore, Jonathan R. Gair