Papers

Optical power densities for standoff spectroscopy, remote sensing, directed energy, and free-space optical communications are limited by diffraction and adverse atmospheric conditions such as turbulence, fog, and wind. Air waveguides, generated by ultrashort-pulsed laser filamentation, are a promising approach for transmission and collection of optical signals over long distances, overcoming beam diffraction and, for point-like sources, inverse square signal falloff with distance. In this work, we demonstrate outdoor guiding for the first time over a record length of ~100 m, exceeding the prior (indoor) record of 42 m. We correlate air waveguide performance to a range of real atmospheric conditions including turbulent refractive index structure parameter ($C_n^2$) values up to ~$2.5\times10^{-14} m^{-2/3}$, crosswind speeds up to ~2 m/s, as well as temperature, pressure, and humidity variations. Accompanying propagation simulations provide insight into the real effects of these environmental perturbations, particularly crosswind, on waveguide performance and lifetime. Our results pave the way for quasi-continuous air waveguiding with kHz-scale repetition rate filaments in challenging outdoor environments.

We study local marginals in one-dimensional translation-invariant quantum systems that may hide finite-period structure. Given an $n$-site reduced density matrix, we ask whether it can be obtained by repeating a finite $p$-site block state along the chain and averaging over the $p$ lattice translations. This defines a symmetrized block-product periodic marginal problem, which provides a route both to diagnosing hidden periodic order from local data and to upper bounding ground-state energy densities of infinite translation-invariant local Hamiltonians. We develop two complementary methods. The first is a semidefinite-programming relaxation based on block permutation symmetry and positive partial transpose constraints, which outer-approximates the convex hull of such marginals and yields certified infeasibility tests. The second is a symmetrized matrix product state ansatz, which constructs explicit block-product periodic states and gives variational upper bounds. We benchmark the framework on the Majumdar-Ghosh model, transverse-field Ising, XX, XXZ, and contextuality-related spin models. The results show that the method captures the expected finite-period structure in exactly solvable cases and gives systematically improving variational energies as the period and bond dimension increase. We also formulate a periodic-NPA relaxation for translation-invariant contextuality witnesses and recover the known quantum limits in the tested examples.

Massive galaxy clusters can introduce gravitational lensing and populations of suppressed star formation member galaxies into the line of sight, potentially changing the distribution of observable sources toward them from that of the average sky. As a result, Fast Radio Bursts (FRBs) aligned with galaxy clusters can provide a unique window into parameter spaces of the FRB population that other lines of sight do not afford. In this study, we demonstrate that the second CHIME/FRB baseband catalog contains FRBs emitted from within or behind clusters identified from the latest DECaLS data release; we isolate a sample of 26 FRBs where this is likely, including one repeating FRB and two FRBs that intersect the Coma cluster. Comparing our results against a range of simulated FRB populations, we conclude that the number of these associations represents a $3\sigma$ rate enhancement toward galaxy clusters, constituting $1.4\pm0.4\%$ of the FRBs detected in the second CHIME/FRB baseband catalog. We suggest that this enhancement is caused by an equal proportion of member galaxies hosting additional FRBs, and gravitational lensing magnifying background sources. We demonstrate that such contributions are sensitive to alternative progenitor channels and high redshift evolution in the FRB population, providing a future avenue for constraining these features. Considering the redshifts and masses of the associated clusters, we identify FRB 20211113A, which is aligned with the strong gravitational lens Abell 2218 as a potential lensed candidate for further consideration.

The minimum-time feedback law for driving a population of coupled oscillators into synchrony is unknown. Here we settle it for identical Kuramoto oscillators under an instantaneous power constraint. Greedy control, maximizing $\dot r$ at each instant, is exactly optimal at $N=2$ and suboptimal above, as dynamic programming confirms at $N=3,4$. The obstruction is geometric: the greedy closed loop is a reparametrized gradient flow of $r$, fixing its path independently of the power budget, and as a first-harmonic forcing it cannot leave a single Möbius orbit. A three-harmonic policy trained on the DP fields, a trajectory expert, and a smooth first-hitting-time objective beats greedy by $10$–$14\%$ at $N=10$–$100$ and matches DP to within $0.3\%$ where ground truth exists. Reading the policy rather than deploying it collapses it to a two-constant law, $u_i\propto-\sin\phi_i+a_2\sin2\phi_i+a_3\sin3\phi_i$, which recovers $84$–$99\%$ of the network's advantage, with the same functional form holding from $N=3$ to $N=1000$. Machine learning discovered a closed-form law beyond the reach of direct analytical methods.

A systematic first-principles investigation of the structural, electronic, mechanical, and optical properties of the cubic C15 Laves-phase intermetallic compound LaMg2 is performed within density functional theory. The calculated elastic constants satisfy the mechanical stability criteria for cubic crystals, confirming the intrinsic stability of the C15 phase. LaMg2 exhibits relatively low bulk, shear, and Young's moduli, indicating enhanced compressibility and elastic softness compared with transition-metal-based Laves phases. Direction-dependent elastic analysis reveals moderate anisotropy in Young's modulus, shear modulus, and Poisson's ratio, whereas linear compressibility remains nearly isotropic, consistent with the high crystallographic symmetry. The ductile nature of LaMg2 is supported by Pugh's ratio and Poisson's ratio, suggesting resistance to brittle failure and the dominance of metallic bonding. Electronic structure calculations confirm metallic behavior with a finite density of states at the Fermi level, primarily originating from La-5d states, accompanied by delocalized charge density characteristic of metallic interactions. The optical response further reflects the metallic nature through high reflectivity, strong optical conductivity at low photon energies, and pronounced absorption in the ultraviolet region. The combination of mechanical compliance, ductility, and metallic optical response highlights LaMg2 as a promising lightweight intermetallic material for applications requiring structural stability, damage tolerance, and efficient electromagnetic shielding or reflective components.

Obtaining equilibrium distributions of nonlinear systems is essential for accurately computing macroscopic observables. Conventional theoretical corrections are typically limited to weak nonlinearities, where interaction terms can be treated as effectively uncorrelated perturbations and the random phase approximation applies. In this Letter, we develop a framework to determine equilibrium distributions based on the generalized energy equipartition principle. Our approach recovers existing corrections in the weakly nonlinear regime and, crucially, remains valid for strong nonlinearities, where perturbative contributions become correlated and conventional approaches break down. Numerical simulations of the nonlinear Schrödinger equation, the Majda-McLaughlin-Tabak model, and the Fermi-Pasta-Ulam-Tsingou model demonstrate accurate corrections for nonlinearities more than an order of magnitude stronger than those accessible to conventional theories.

Determining microscopic interactions from spectroscopic and scattering measurements is central to understanding quantum materials, yet it often remains unclear which interactions can be reliably revealed by the available experimental data and how additional experimental modalities should be designed to resolve the remaining ambiguities. Here we present an artificial intelligence-enabled framework for uncertainty-aware Hamiltonian inference and adaptive experimental design. By combining Hamiltonian-conditioned neural surrogates with Bayesian inference and observation geometry, the framework characterizes how measurements constrain Hamiltonian parameter space, quantifies the identifiability of microscopic interactions, and propagates posterior uncertainty directly in the physical Hamiltonian parameter space rather than an abstract learned representation. Using multimodal powder and single-crystal inelastic neutron scattering measurements of the quantum magnet NiPS$_{3}$, we demonstrate physically interpretable Hamiltonian inference, modality-aware uncertainty quantification, and adaptive experimental design. The framework provides a general strategy for uncertainty-aware microscopic characterization and multimodal experimental design across quantum materials.

We investigate how the sewing operations familiar from topological quantum field theory provide a useful organizational framework for semiclassical AdS/BCFT path integrals. Our purpose is not to identify AdS/BCFT with a topological field theory: the bulk geometry, the end-of-the-world brane, and the on-shell action remain intrinsically metric-dependent. Rather, we use the TQFT language of state preparation, orientation reversal, and gluing to separate interface data from local geometric contributions. For AdS$_3$/BCFT$_2$, we review how the Euclidean on-shell action and the Ryu–Takayanagi prescription reproduce the Affleck–Ludwig boundary entropy $\log g$ after holographic renormalization. We then formulate the Complexity=Action calculation in the presence of an end-of-the-world brane, carefully distinguishing bulk, brane, joint, and null-boundary contributions. We emphasize that finite terms in a relative Wheeler–DeWitt action depend on the choice of regulator matching and on the null-boundary counterterm scheme unless their scheme independence is established explicitly. Finally, we extend the geometric construction to a planar BTZ background and derive the brane embedding from the Neumann boundary condition. The resulting framework clarifies which aspects of holographic complexity are sensitive to boundary conditions and which require further renormalization input before they can be interpreted as universal boundary data.

Understanding the evolution of the cosmic star formation rate density (SFRD) is key to uncovering how the Universe arrived at its present state. This paper presents a novel and efficient method to estimate the local SFRD, which uses supervised machine learning to first identify a population of star-forming galaxies (SFGs). Next, star-formation rates (SFRs) are determined using the 1.4-GHz radio-continuum emission detected by the Australian Square Kilometre Array Pathfinder (ASKAP). Specifically, a gradient-boosted decision tree model was implemented to classify extragalactic sources from the Beck et al. (2022, MNRAS, 515, 4711) catalogue as either galaxies or quasars using RACS-mid and WISE photometry. The full sample, consisting of 389,392 sources, was partitioned into a 70%-15%-15% split for training, validating, and testing. The optimised model achieved a weighted F1 score of 0.93 and an accuracy of 0.94 on the test dataset, ultimately classifying 336,674 sources as galaxies and 52,718 sources as quasars. Using the resulting $z<0.1$ depth-matched galaxy sample and the photometric redshift predictions from Beck et al. (2022, MNRAS, 515, 4711), a modified 1.4-GHz SFR calibration was determined, yielding a local, completeness-corrected, $z<0.1$ SFRD of $(1.4 \pm 0.5) \times 10^{-2} \; \rm M_{\odot}\, yr^{-1}\,Mpc^{-3}$ using 11,293 sources. This value is consistent with previous results. Thus, this study demonstrates the feasibility of using supervised learning to identify large populations of SFGs in order to investigate the SFRD evolution. This presents an exciting prospect for future, deeper surveys such as EMU, which will enable the cosmic SFRD to be probed out to higher redshifts.

Thermo-mechanical compliant devices are commonly designed with small-strain linear elasticity and temperature-independent material properties, even though they might operate hundreds of kelvin above ambient where both assumptions are questionable. In this work, we quantify the effect and cost of each assumption in multi-material topology optimization of thermally actuated compliant devices. To this end, we introduce a physics-informed, simultaneous analysis-and-design framework with (i) a finite-strain quadratic-Hencky (logarithmic-strain) constitutive model whose isotropic thermal eigenstrain admits an exact additive split in log-strain space, and (ii) temperature-dependent conductivity, thermal expansion, and elastic moduli for a titanium–copper–steel material system. We optimize a thermal actuator and a thermal gripper at three design temperatures under both a baseline model and the full physics, subject to mass and manufacturability constraints. Every converged design is re-evaluated by verified nonlinear finite element solvers in the full factorial of constitutive law and property model. The comparison between the two factors reveals that the constitutive law is the decisive modeling choice: These devices work as linkages where linear kinematics mistakes rotation for compressive strain; its error therefore grows with the design temperature and concentrates on the very layouts that exploit rotation best. Because a linear optimizer also steers away from the rotation-rich mechanisms that would expose this bias, the model can deceptively appear trustworthy when validated against its own designs. Designing with the full physics yields consistently stronger and more temperature-robust devices at a modest increase in design-time cost.

While deep learning-based denoising has become widely adopted in low-dose CT, conventional models use generic architectures designed for natural images, failing to account for non-stationary and spatially correlated CT noise characteristics. To address this, we propose an Efficient Noise COntext-aware REpresentation (ENCORE) framework that explicitly leverages CT noise characteristics and anatomical features. First, we reformulate the noise synthesis procedure based on a realistic noise distribution beyond the conventional Gaussian approximation, establishing a rigorous foundation for training pair generation. Next, we extract local noise power and correlation contexts to guide the denoising process. To fully leverage the potential of noise context, we propose a FlyingConv module, which adaptively changes convolution weights for each local image region. Notably, our approach demonstrates substantial gains in both denoising quality and computational efficiency. Furthermore, manipulating the intensity of the noise context maps at inference time enables zero-shot conditional denoising, allowing for dynamic control over the output image texture. The entire pipeline is available at https://github.com/minwoo-yu/ENCORE.git

Radial vortex is a topological spin texture stabilized by the interfacial Dzyaloshinskii-Moriya interaction (DMI) in ferromagnetic disks. Previous investigations have shown that the doublet splitting of azimuthal modes in traditional circular vortices arises from the coupling between azimuthal spin waves and vortex core (VC), an effect occurs only for azimuthal indices $m=\pm1$ and is absent for higher-order modes. Here, we present a giant mode splitting of azimuthal spin waves in radial vortices, even in the absence of the VC. This mode splitting arises from the DMI, which can be an order of magnitude larger than that induced by the VC. Moreover, the DMI-induced frequency splitting increases with both the DMI constant and mode index, reaching tens of GHz for higher-order azimuthal modes. Our results reveal a robust mechanism for mode splitting in chiral magnetic textures and deepen the fundamental understanding of the DMI effect on the spin-wave dynamics in confined magnets.

The redistribution of the wave feature, particle feature, and mixedness is investigated for two-qubit isotropic states in Schwarzschild spacetime under Hawking radiation and environmental decoherence. It is shown that Hawking radiation changes their relative weights among different horizon regions rather than simply suppressing them. The analysis is further extended to phase damping, phase flip, and bit flip channels. Phase damping monotonically suppresses the wave feature and enhances mixedness, phase flip produces a symmetric death-and-revival behavior of the wave feature, and bit flip mainly reshapes the particle feature and mixedness through diagonal population redistribution. However, although Hawking radiation and channel noise affect the distribution of wave feature, particle feature, and mixedness in the subsystems, the triality relation among them still holds and remains unaffected by thermal and environmental noises.

Computational head models are typically applied to isolated impacts, leaving repeated head loading largely unexplored. An Ogden-Roxburgh Mullins damage formulation was implemented in a high-fidelity finite element head model to represent loading-history-dependent softening during cyclic brain-tissue deformation. Repeated-loading histories derived from mixed martial arts head-impact data were applied and compared with damage-free hyperelastic (HE) and linear visco-hyperelastic (LVHE) model variants. Under five identical single-axis cycles, Mullins-type softening progressively increased strain and strain rate metrics relative to the HE model. Mullins-based injury probabilities progressively exceeded strain-based HE predictions and diverged from unchanged kinematics-based predictions, indicating that neglecting prior softening may underestimate injury risk. In a randomized twenty-cycle multiaxial sequence, cycles of similar kinematic intensity produced different deformation and injury-risk estimates depending on prior softening. HE and LVHE models predicted higher injury probabilities initially, whereas the Mullins-based model produced the largest later-cycle estimates and highest probability of at least one injury over the sequence. Regional amplification depended on loading direction and prior softening, with no direction-independent trend among brain substructures. Gyral elements exhibited higher cumulative maximum principal strain than sulcal elements, which showed greater amplification relative to initial responses. These findings demonstrate that short-term damage-mediated softening can substantially amplify tissue deformation and injury-risk estimates beyond damage-free head models under the same loading histories. Further experimental characterization of cyclic brain-tissue softening is needed to improve models of repeated head loading and traumatic brain injury.

High-order shock-capturing schemes often face severe computational bottlenecks due to wide stencils, stagewise nonlinear weights, and expensive local characteristic decompositions. To address this, we propose a compact finite-average-moment (FAM) framework for hyperbolic conservation laws that completely decouples the formal spatial order from the number of evolved local degrees of freedom. By evolving only a $\mathbb{P}^1$ moment state (i.e., cell averages and scaled first-order moments), we achieve up to sixth-order accuracy ($k=3, 4, 5, 6$) via compact, polynomially exact linear moment reconstructions. A key algorithmic innovation is consolidating the nonlinear stabilization into a single, derivative-free oscillation-elimination (OE) procedure applied only after the final Runge–Kutta stage. This OE procedure exactly preserves cell averages while applying an explicit exponential correction to the first-order moments, avoiding repeated stagewise nonlinear weights or limiting. Fourier analysis of the linear backbone demonstrates $k$th-order accuracy, strong spurious mode damping, and $(k+1)$th-order cell-average superconvergence. Extensive numerical experiments on scalar laws and the Euler equations verify the expected smooth accuracy and robust, nonoscillatory shock resolution. Notably, by performing componentwise reconstruction directly in conservative variables and streamlining stabilization, the FAM schemes deliver significantly lower complete-run wall-clock times compared to the multi-resolution weighted essentially non-oscillatory (MR-WENO), unified-stencil Hermite WENO (HWENO-U), and OE-HWENO methods.

Existing methods for calibrating and classifying Doppler lidars for wind energy applications are time-consuming and overestimate lidar measurement uncertainty. These shortcomings are due to the reference instruments: anemometers on meteorological masts. The input signals in field calibrations are real wind conditions, and include uncertainties associated with the met mast and the terrain. This research presents validation of a new method for lidar calibration. The new approach has two steps. First, the uncertainty of the lidar line of sight velocities (LOS) are measured. Second, those intermediate uncertainties are used to derive the uncertainty of the horizontal wind speed using a simulated wind field. LOS uncertainties are assessed using a fiber optic bench as a synthetic wind tunnel called Simulation of the Atmosphere with Fiber Optics Multi-Velocity (SAFO-MV). Using SAFO-MV, the lidar LOS is shifted using an acousto-optic modulator (AOM) and backscattered from a fiber spool, mimicking backscatter from a uniform, low turbulence wind field. The reference signals are SI-traceable via calibration of the AOM's RF-driver. Sources of uncertainty in the bench and the laboratory process are examined and found to be small. Wind speed uncertainties are derived via Monte Carlo uncertainty propagation. Wind fields are simulated using PyConTurb, an implementation of the KSEC turbulence model. A virtual lidar in the simulation replicates lidar sensitivities derived by IEC 61400-50-2 classification campaigns. Replication of device sensitivities and the traceability of the approach comprise a validation of the measurement model, enabling its use for lidar calibration. The proposed method yields uncertainties comparable to IEC lidar calibration, while greatly reducing calibration time. This new technology can streamline lidar deployment and reduce uncertainty in wind resource assessment.

This work examines the physical characteristics of charged, anisotropic compact spheres within the framework of $f(R,\phi,X)$ modified gravity. Starting from a static, spherically symmetric spacetime, we employ an Adler-type ansatz for the temporal metric component $g_{tt}$. The corresponding radial metric component $g_{rr}$ is then systematically derived through application of the Karmarkar condition, which ensures a class-one embedding for the interior geometry. A crucial aspect of our approach involves matching the interior solution at the stellar boundary to the exterior Reissner–Nordstr$\ddot{0}$m spacetime—the established vacuum solution for charged, non-rotating masses. This matching procedure is essential for determining integration constants and verifying global physical consistency. Our comprehensive analysis of the resulting stellar model investigates multiple physical aspects, including energy density, radial and tangential pressures, anisotropy, equation-of-state parameters, energy conditions, mass function, compactness, and surface redshift. Stability assessment further incorporates examination of the adiabatic index and the Tolman–Oppenheimer–Volkoff equation. Collectively, our findings demonstrate that the charged compact star model presented here constitutes a physically viable configuration—free of singularities and maintaining stable equilibrium across the considered parameter space.

We investigate late-time Barrow holographic dark energy (BHDE) with Ricci cutoff in $f(Q,L_m)=Q+\alpha Q^n-2L_m$ gravity. The $Q^n$ term modifies the symmetric-teleparallel geometry, while $\Delta$ deforms holographic energy via entropy-area relation. Linear matter Lagrangian allows separate identification of geometric and holographic effects. Modified Friedmann equations with Ricci-cutoff BHDE yield a closed first-order equation for $E(z)=H(z)/H_0$, solved numerically. The model evolves from matter domination to late-time acceleration. Increasing $n$ makes $w_{\mathrm{DE},0}$ less negative, raises $z_t$, lowers $j_0$; increasing $\Delta$ makes $w_{\mathrm{DE},0}$ and $q_0$ more negative, raises $z_t$ and $j_0$. Calibrating $\mathcal{C}_{B,\mathrm{ref}}$ with $q_{0,\mathrm{ref}}\simeq -0.527$ gives $w_{\mathrm{DE},0}\simeq -1.003$, $z_t\simeq0.442$, $j_0\simeq1.486$. Two-dimensional $(n,\Delta)$ maps show opposite effects on $w_{\mathrm{DE},0}$ but same direction on acceleration onset. We compare expansion histories with 36 cosmic-chronometer measurements ($0.07\leq z\leq1.965$), using DESI covariance and asymmetric error at $z=0.8$. Comparison is conditional for fixed trajectories, without fitting; Hubble statistic varies modestly. Results provide a consistent background realization of Ricci-cutoff BHDE in $f(Q,L_m)$ gravity and motivate future perturbation and multi-probe studies.

We extend Thorpe successive approximation expansion to the forced, tide locked internal wave generation problem of Lamb and Dunphy, where a barotropic tide over a ridge radiates a discrete spectrum of Taylor Goldstein eigenmodes in a steady shear current. At second order in topographic steepness, each mode forces a bound second harmonic via diagonal mode pair kernels derived in closed form; both kernels vanish for uniform flow, recovering Thorpe limit. At third order, solvability of the resonant fundamental yields a nonlinear wavenumber correctionthe forced counterpart of Thorpe phase speed shift, with tidal frequency fixed. Computations at the parameters of Lamb and Dunphy show that the corrections are small but systematic, with the bound harmonic distorting the displacement profile modestly and concentrated in the surface shear layer for downstream modes. The corrections peak at modes 2 to 3, grow quadratically with ridge height and current strength, and amount to a nonlinear slow-down of every mode, explaining from within the theory why the linear discrete spectrum model agreed so well with fully nonlinear simulations. A pycnocline case with stratification colocated with the shear layer amplifies the nonlinear corrections substantially, showing that the uniform stratification verdict is not generic and that the corrections are controlled by where N2 sits relative to the shear.

We develop a diffeological framework for the geometry of Euler–Reynolds subsolutions of the incompressible Euler equations. Passing to a lifted formulation in which the velocity, quadratic flux, and trace-free Reynolds stress are treated as independent variables, we construct a diffeological limit space obtained as the weak closure of smooth strict subsolutions. Its internal tangent spaces provide an intrinsic notion of infinitesimal deformation despite the absence of any underlying manifold structure. We prove that ambient realizations of internal tangent vectors satisfy the linearized Euler–Reynolds equations in the sense of distributions, thereby establishing a natural first-order theory for lifted weak limit spaces. We further describe the tangent directions compatible with the Euler locus and identify the kernels of the natural velocity, flux, and full-state observables. These results distinguish observable perturbations from hidden stress-gauge directions that encode infinitesimal variations of the Reynolds stress. Finally, we introduce a finite-mixture model for lifted Euler–Reynolds states whose differential realizes explicit tangent directions and relates Reynolds stress to infinitesimal phase splitting. Under a genericity assumption, every deviatoric stress tensor is realized by such a first-order mixture defect, yielding phase-counting bounds and a minimality result for the observable hierarchy.

This thesis studies exact, deterministic preparation of arbitrary dense n-qubit states, the data-loading step in quantum signal and image processing. It derives two syntheses built on the Digital Signal-induced Heap Transform (DsiHT): the QsiHT Fast Path Real Synthesis and the QsiHT Fast Path Complex Synthesis. Both are benchmarked against ten configurations spanning the UCR, isometry, multiplexor, Schmidt/SVD, QSD, and heap-transform families. Several of those are realizations through Qiskit builders or compiler optimization, not from-scratch reimplementations. The n=3 noisy comparison spans ibm_fez, ibm_kingston, and ibm_marrakesh, three 156-qubit IBM Heron r2 processors, where single-submission nine-method jobs permit within-session family-wide Benjamini-Hochberg-corrected comparisons. The frontier-versus-QSD separation reproduces within one calibration on every device, but the within-frontier order does not reproduce across devices or calibration days. A deep-circuit n=8 run on ibm_fez shows the executed-count ordering re-emerge outside the run-to-run spread on the complex target. Depth was not isolated from mapping, gate composition, calibration, or session effects. All methods are exact to machine precision and differ only in cost. Under noise the coarse error tier tracks the executed (routed) two-qubit count, separating the Theta(2^n) frontier from QSD's Theta(4^n) and nothing finer. Both syntheses realize the deployed Qiskit StatePreparation floor of 2^n-n-1 CNOTs, undercutting every other from-scratch method on the as-built CNOT axis. The Real Synthesis serves real (sign-bearing) targets and holds the lowest classical build cost among the exact loaders at large register sizes, through one fast Walsh-Hadamard pass. The Complex Synthesis serves arbitrary complex targets and ties Qiskit's StatePreparation for the lowest simulated sampled error.

Let $\mathcal H$ be a finite-dimensional complex Hilbert space, and let $w(P,\mathsf M)$ be a normalized probability weight assigned to an outcome projection $P$ as it occurs in a projective measurement $\mathsf M$. For fixed $P$, let $G_P\cong\mathcal U(P^\perp)$ be the group of unitaries acting identically on $\operatorname{ran}P$ and arbitrarily on $P^\perp$. We classify the $G_P$-orbits of projective measurements containing $P$: two measurements lie in the same orbit exactly when the multisets of ranks of their complementary outcomes agree. The orbit with profile $\lambda=(r_1,\ldots,r_k)$ is a compact homogeneous space of real dimension $(d-\operatorname{rank}P)^2-\sum_j r_j^2$. On maximal rank-one measurements there is one orbit, so context independence is equivalent to $G_P$-invariance, with equality of the corresponding uniform defects; invariance under two-level complementary unitaries already suffices. For arbitrary projective measurements, every context containing an outcome $P\neq I$ coarsens to the unique binary context $\{P,I-P\}$. Consequently, refinement consistency alone is equivalent to context independence. The finite orbit space carries a natural rank-profile refinement graph, whose diameter is $d-\operatorname{rank}P-1$ when $P\neq I$. We prove a stability theorem that compares the binary-coarsening path with a shortest path in this graph followed by one complementary unitary. In dimension at least three, Gleason's theorem converts the maximal-context invariance condition and the all-context refinement condition, on their respective domains, into the Born form $\operatorname{Tr}(\rho P)$. The results are structural characterizations, not independent physical derivations of context independence.

Discrete symmetries in gravity have only been tested for low energy, non-relativistic matter, confirming the perfectly symmetric general relativity. A hint for high energy $\cal{CP}$ violation in gravitational fields has recently been found in the HERA Compton polarimeter's two spectra, measured with electron and positron beams. Here we report results of the analysis of the same polarimeter's 314896 spectra, acquired during 2004–2007 and tagged by laser polarization states allowing the separation of charge ($\cal C$) and space parity ($\cal P$) contributions. The measured Compton edge energy asymmetry, induced by the laser helicity flips, is as high as $(4.9\pm0.5)\cdot10^{-5}$ which corresponds to a helicity-dependent difference in the gravitational potentials of $(1.7\pm0.2)\cdot10^{-14}$. In the case of the observed anomalous coupling's energy independence, the spin asymmetric gravity will contribute to the galactic rotational curves. Further analysis and calculations can determine whether the observed magnitude of the gravitational parity violation is sufficient for detaching this famous phenomena from the dark matter theory.

We develop an integrability framework for Hamiltonian dynamics on con-locally conformal symplectic (COLCS) manifolds, odd-dimensional quadruples $(M,\Omega,\theta,\eta)$ where $d\Omega=\theta\wedge\Omega$, a closed $1$-form $\eta$ determines a codimension-one distribution on which $\Omega$ is non-degenerate, and $R$ is the Reeb vector field satisfying $\iota_R\Omega=\iota_R\theta=0$, $\iota_R\eta=1$. This class simultaneously generalises LCS and cosymplectic manifolds and provides a natural arena for time-dependent Hamiltonian systems with twisted differential $d^\theta=d-\theta\wedge$. The COLCS bracket is introduced on $C^\infty(M)$ and shown to be a Lie bracket that induces Poisson structures on the subalgebras of $\theta$-strong ($\theta(X_H)=0$) and $R$-strong ($R(H)=0$) functions. A Lie-type integrability theorem is then established: given $2n-k$ functionally independent first integrals with $k$ of them $\theta$-strong and generating a solvable Lie algebra under the COLCS bracket, the flow is integrable by quadratures on the common level set. Finally, scaling symmetries of degree $(\Lambda,\beta,\gamma)$, defined by $L_X\Omega=\beta\Omega$, $L_XH=\Lambda H$, $L_X\eta=\gamma\eta$, are studied: they rescale $X_H$ by $(\Lambda-\beta)$, generate families of first integrals, and imply structural primitives for $\Omega$ and $\eta$.

Starting from the constrained variational formulation of Larché and Cahn for solids in contact with fluids, a unified thermodynamic framework for such systems is developed. Both bulk and interfacial equilibrium conditions arise as stationarity conditions of a single thermodynamic functional. While earlier theory neglects a full treatment of interfacial contributions and therefore cannot describe systems in which surface effects are significant, the present formulation incorporates interfacial thermodynamics directly into the variational principle. The framework is introduced first for fluid-fluid systems to establish the underlying mathematical structure, and is then extended to solid-fluid interfaces. Within this setting, classical equilibrium relations for heterogeneous systems emerge naturally from different classes of admissible variations, providing a common theoretical basis for bulk, interfacial, and configurational thermodynamics.

We examine whether the citations received by refereed astronomy papers vary systematically with the day of the week of their arXiv preprint release. We use NASA ADS citation data for all refereed articles published in 2020–2023 in six journals (MNRAS, ApJ, ApJL, ApJS, A&A and JCAP; 37,173 papers with astro-ph primary preprints), combined with version-1 submission timestamps from the arXiv API. We group papers both by submission weekday and by the day their announcement batch appears on arXiv, accounting for arXiv's weekday deadline and lack of weekend announcements. Given the heavy skew of citation distributions, our primary statistic is the median citations per group, with bootstrap confidence intervals. Papers submitted on weekends, all of which appear in the Monday listing, have median citations significantly lower than weekday submissions in five of the six journals, by 12–26 %; the sixth (JCAP) shows the same direction, but not significantly, consistent with its small weekend sample. Median citations are indistinguishable across the five weekdays. These results extend the recently reported weekend citation disadvantage in particle and nuclear physics to astronomy. The link is correlational, consistent with either compositional variations in weekend submissions or reduced visibility in the enlarged Monday listings.

The interplay between luminous matter distribution and the local gravitational field within disc galaxies encodes physical information beyond that captured by global scaling relations. We introduce a dynamical–photometric phase space defined by the kinematic variable $X(R)=V(R)/R$ and the photometric variable $Y(R)=\mathrm{d}\ln I/\mathrm{d}\ln R$, placing the local gravitational scale and the logarithmic surface brightness gradient into direct pointwise correspondence at each galactocentric radius $R$. The quantity $X=V/R=\omega$ represents the angular frequency of circular motion and acts as a probe of the local mean mass density, while $Y$ measures the radial steepness of the stellar light distribution. The baryon-dominated inner disc is characterized by large negative $Y$, whereas the dark-matter-dominated outer region approaches $Y\rightarrow0$. This two-regime behaviour is described by the smooth sigmoid relation $Y=[a\ln X+b]/(1+\exp[k(X-X_{\rm trans})])$, which reduces to the logarithmic coupling $Y=a\ln X+b$ in the baryonic zone. We apply this framework to 136 late-type galaxies from the SPARC database, spanning inclinations $20^{\circ}$–$89^{\circ}$, distances $1$–$130$\,Mpc, and five decades in stellar mass. The median coefficient of determination is $R^{2}=0.930$. Statistical validation includes eight independent tests together with 5-fold cross-validation. The transition parameter $X_{\rm trans}$ identifies the onset of dark-matter dominance, corresponding to a median transition radius $R_{\rm trans}=5.40$\,kpc across the sample.

Long term operation of semiconductor spin qubits requires active stabilization of quantum dot potentials against low-frequency charge noise. To address this, we demonstrate a gradient-descent feedback approach in a silicon double quantum dot device using high-bandwidth radio-frequency (rf) reflectometry readout and a field-programmable gate array (FPGA) for digital signal processing. This architecture enables continuous multi-parameter gradient calculation and quick gate voltage updates, significantly increasing the effective feedback bandwidth compared to previous methods relying on slow direct-current transport measurements. By operating with 8 steps per feedback cycle and an integration time of 25.6 $\mu$s, this high-speed stabilization scheme maintains better than -6 dB of noise suppression up to 5 kHz, achieving an attenuation of $-7.4 \pm 0.2$ dB at the maximum measured frequency. This effectively suppresses low-frequency 1/f noise, maintaining device stability over longer time periods, and potentially enables real-time control in large-scale quantum dot arrays.

A verbal theory does not run: translating it into an executable model requires choices about variables, interventions, and interactions. We tested whether the presentation of otherwise identical theoretical content systematically changes the programs produced by large language models. In a prospective preregistered randomized experiment, 16 independent assignment bits allocated 32 paired renderer slots between a structured intervention contract and connected prose. Two pinned LLM snapshots translated five anonymous theoretical accounts, yielding 320 preauthorized single-shot programs in a frozen sparse quadratic language. A deterministic evaluator measured atomic finite-difference responses (H1) and mixed interaction responses (H2). Two primary endpoints assessed cross-model matched-distance reduction and closed-set same-account identifiability, with exact randomization inference and 27 preregistered support criteria evaluated across signed-linear and magnitude-rank pipelines. Both H1 and H2 returned the registered verdict NOT_SUPPORTED; only 19 of 108 criterion evaluations passed. Same-account identifiability remained near chance (AUC 0.469-0.523, against a registered 0.80 threshold). One H2 matched-distance endpoint moved and survived multiplicity correction in the signed-linear pipeline, but the corresponding magnitude-rank result missed the registered effect-size floor, so it did not satisfy the joint support rule. Thus renderer format did not produce the uniform, family-invariant, classifiable behavioral geometry predicted in advance. The result places a concrete boundary on specification-format effects in LLM theory-to-program translation and provides a fully auditable randomized design, datasets, and software for studying executable formalization.

Angle-resolved photoemission spectroscopy (ARPES) can measure electrons' energy vs momentum relations in solids via photoelectric effect. This pedagogical paper experimental results from this technique as a tool for visualizing the Fermi gas model in quantum statistical mechanics. This model is an important starting point for understanding more complex electronic behaviors in real metals.