Papers

The HYDRA (HYpernuclei Decay at R$^3$B Apparatus) TPC is a 5,376-channel pion tracker developed for hypernuclear studies at the R$^3$B experiment at GSI/FAIR. Its installation inside the GLAD dipole magnet imposes strict space constraints above the pad plane. To fit the front-end electronics within this volume, the VMM3a/SRS readout was adapted through a vertical hybrid arrangement and custom boards for signal routing and power distribution. At the same time, the readout had to be integrated with the R$^3$B timing system, which is not natively supported by the SRS. This was achieved by recording the R$^3$B heimtime and trigger signals through spare VMM3a channels, allowing the global timestamps to be reconstructed from the same data stream. Simulations of the PCB coupling indicated low crosstalk between adjacent traces, while S-curve measurements gave a baseline noise level consistent with that reported for the standard VMM3a/SRS readout. Cosmic-muon measurements with the plastic wall provided reconstructed tracks and confirmed event-by-event timing correlation between the two detector systems.

We present a quantum algorithm for simulating Generalized Parton Distributions (GPDs) in the Schwinger model. Unlike the staggered fermions widely utilized in current quantum simulations, we employ Wilson fermions for lattice discretization. This choice is critical for the quantum computation of GPDs due to their strict preservation of charge conjugation symmetry. We construct a comprehensive algorithmic framework that includes the preparation of hadronic states with non-zero momentum and the measurement of light-cone correlation functions incorporating Wilson lines. We provide a complexity analysis, demonstrating that the resources required for our algorithm scale polynomially with both the number of qubits and the desired precision $\varepsilon$. Finally, we benchmark our approach using exact diagonalization, extracting mass spectra and GPDs (also parton distribution functions) that are consistent with theoretical expectations and fundamental physical constraints.

A holographic code assigns a state-dependent entropy remainder to every boundary region, but such remainders need not be the extremal lengths of any one bulk metric. We study this common-source question for the proto-area of a calibrated recovery, the entropy of a boundary region minus that of the matter recovered from it. At zeroth order the reference values must match the lengths of one reference geometry in a fixed renormalization scheme, and this matching also determines the entropy-to-length factor. On a graph with a fixed minimum-cut chamber the data derivatives must lie in the image of the cut-incidence matrix, whose left null vectors are witnesses. On the hyperbolic disk the first variation of renormalized length is the rank-two geodesic X-ray transform, with closed range in an adapted data space, and the geodesic displacement, fixed by a forced Jacobi equation, enters at second order. The resulting normal Hessian gives a gauge-invariant criterion, necessary and sufficient, for a regular pair of response coefficients to come from one metric two-jet. For the constant-curvature family generated by a boundary reparametrization the Hessian has a nonzero rank-four mode, so the image of the length map is curved. For a fixed recovery the proto-area Hessian is minus the Bogoliubov-Kubo-Mori information lost in recovery, which the Petz map decomposes orthogonally at a product reference, and which, on a finite-dimensional space of logical directions with positive minimum retained fraction, is at most a sharp multiple of the retained information. Geometric realization requires this loss to reproduce the normal length Hessian on every interval. Two codes show that exact regional area operators can fail to sew into one graph geometry, and that a matched reference with vanishing first response can fail at second order. All criteria refer to one recovery branch and one extremal-surface branch.

We present a unified, multi-scale study of non-Gaussianity of Galactic foreground emissions using Minkowski Functionals and generalized skewness-kurtosis parameters, focusing on the characterization of small-scale non-Gaussianity and its underlying physical origin. We find that all foreground components studied exhibit a remarkably universal non-Gaussian nature dominated by excess kurtosis, whose shape remains stable across angular scales despite large differences in emission physics. Focusing on thermal dust, we perform a detailed comparison between observed maps (GNILC and Planck 545 GHz) and dust model realizations (PySM and filament-based models) to assess the performance of state-of-the-art models in reproducing the observed non-Gaussian properties. At the global level, GNILC and PySM display closely matched kurtosis behavior over the angular scales where the GNILC reconstruction is reliable, while the filament-based model produces substantially weaker skewness and kurtosis signals. For PySM, however, a patch-based analysis reveals statistically significant regional variations, indicating that while the model reproduces the overall non-Gaussian amplitude and scale dependence, it does not fully capture the spatial variability of the observed kurtosis signal. Using simple PDF-based toy models, we demonstrate that the universal kurtosis signature arises from the combination of heavy-tailed one-point statistics and steep large-scale spatial correlations, while its detailed amplitude and scale dependence depend on the underlying foreground physics. These results identify excess kurtosis as a robust statistical fingerprint of Galactic foregrounds and provide a practical framework for validating small-scale foreground models for future CMB analyses.

We present a study of two tailed radio galaxies in the core of a massive, dynamically young galaxy group - an early group-group merger. Using VLA (3 GHz and 1.4 GHz), MeerKAT (1.35 GHz), and GMRT (610 and 325 MHz) observations, we investigate their radio spectral properties, spectral and dynamical ages. Radio morphologies show clear evidence of interaction with the intragroup medium (IGM). One galaxy is a wide-angle tail (WAT) source, while the other is most likely a head-tail (HT) galaxy. Both galaxies exhibit high radio luminosities, and we find spectral indices of $\alpha=0.8\pm 0.1$ (WAT) and $\alpha=0.6\pm 0.2$ (HT). Spectral index analysis reveals spectral steepening with distance from the core in both galaxies, with localized flattening in the WAT lobes and hotspots along the northern jet, and indications of such flattening in the middle of the HT tail. Spectral ages derived using Jaffe-Perola model are $33.80\substack{+7.63 \\ -7.23}$ Myr (WAT) and $20.86\substack{+10.07 \\ -17.17}$ Myr (HT), significantly lower than dynamical ages of $420\pm60$ to $700\pm100$ Myr (WAT) and $140\pm20$ Myr (and possibly up to $280\pm40$ Myr, for HT), yielding dynamical-to-spectral age ratios of $\sim12-20$ and $\sim7$ (and up to $\sim14$), respectively. The discrepancy may be reduced by using more complex dynamical age models, incorporating interactions with the IGM, which requires deeper X-ray observations of the group. Spectral age estimates may be affected by mixing of electron populations, and could be better constrained with future deep, high-resolution broad-band radio observations at both MHz and frequencies above 3 GHz. The combination of extended radio structures, spectral signatures of radiative aging with localized re-acceleration, and activity timescales up to hundreds of Myr indicates that galaxies are actively interacting with, and likely depositing energy into their environment.

High qubit overhead is a key bottleneck for fault-tolerant quantum computation. Quantum low-density parity-check (qLDPC) codes offer high encoding efficiency but typically require non-local connectivity in every syndrome extraction cycle, incurring additional physical errors and implementation complexity. We introduce a hierarchical logical processor (HLP) architecture that implements a high-rate quantum CSS code with distance-$d_{0}$ rotated surface codes (RSC), allowing long-range connectivity to be used only once every $\Theta(d_{0})$ rounds of surface-code syndrome extraction. HLPs introduce elongated RSC patches called shuttle buses. Using transversal hybrid-unit CNOT gates, a single shuttle bus can simultaneously couple to multiple standard RSC patches. This capability enables efficient level-1 syndrome extraction with suppressed level-1 error correlations and supports highly parallel logical Pauli measurements. We perform circuit-level simulations of several concrete HLP constructions and benchmark both logical memory and logical Pauli measurement performance. At a physical error rate of $10^{-3}$, a hierarchical logical processor can achieve 3-4 times higher qubit efficiency than the rotated surface code and 20-30 times shorter logical error-correction cycle times than the yoked surface code.

Why would anyone help a stranger, knowing they may never meet again? Indirect reciprocity offers one of the most compelling evolutionary answers, yet its two canonical forms – upstream reciprocity (experience-based), and downstream reciprocity (reputation-based) – have been studied mostly in isolation. Their joint dynamics in finite and structured populations remain largely unexplored. Here, we fill this gap using agent-based simulations in which an agent is behaviourally either defector, upstream reciprocator, or downstream reciprocator, and the agents' population state is temporally updated using different evolutionary update mechanisms. We show that update mechanism plays a surprisingly decisive role in shaping the fate of downstream and especially upstream reciprocators. Whether agents' experiences and reputations are updated globally or locally can shift outcomes from rich behavioural coexistence to the dominance of downstream reciprocators alone. Intriguingly, we uncover a robust structural feature that persists across all the explored update rules and population sizes: an optimal network degree at which upstream reciprocity is maximized, reflecting a fundamental tug-of-war between cooperative clustering and exposure to defectors. Our results highlight that while downstream reciprocity can either foster or inhibit upstream reciprocity depending on the update mechanism, its net effect on cooperation remains largely positive.

Parameterized descriptions of black-hole quasinormal-mode spectra are essential for testing gravity with ringdown observations. We extend the Parameterized Spin Expansion Coefficients (ParSpec) formalism by simultaneously sampling the characteristic length scale $\tilde{\ell}$ and the scaling index $\tilde{p}$, rather than fixing $\tilde{p}$ to a theory-motivated integer and constraining $\tilde{\ell}$. Physically, this extension promotes the scaling of the spectral corrections coming from higher-curvature operators to an observable quantity. Methodologically, it enables us to investigate the enlarged ParSpec parameter space and identify the prior geometry induced by conditions on the effective coupling $\gamma$. We examine the robustness of the framework by using the $220$ and $220+221$ ringdown models over different start times with informative priors on mass and luminosity for GW250114, and further study a joint constraint with GW231123. We pointed out that $\gamma<1$ avoids an artificial correlation between $\tilde{p}$ and $\tilde{\ell}$ among the coupling prescriptions considered, and the choices of ringdown starting time and QNM mode content in the ParSpec framework should be matched to the information content and resolving power of the data. Higher-SNR ringdowns and hierarchical analyses of a larger event population will be required to break the $\tilde{p}$-$\tilde{\ell}$ degeneracy and directly probe the scaling structure of corrections to GR.

We present an investigation of the Tully-Fisher (TF) relation solely for galaxies hosting an active galactic nucleus (AGN). Using 22 galaxies with primary, z-independent distances, we find that active galaxies exhibit significantly larger scatter about all TF relations compared to each respective calibration for (largely) inactive galaxies. The larger scatter persists despite removal of the AGN contamination from the photometry of the Type 1 AGNs via 1) careful surface brightness decompositions or 2) employing SEDs to constrain the light contribution of the AGN. These results suggest that the influence of an AGN on its host galaxy's surface brightness may extend beyond the nucleus. We also calculate the percentage difference between TF and primary distances, and find that TF-based distances are biased towards overestimation of the primary distances to active galaxies by anywhere from 5-10 percent for the optical/near-infrared and approximately 15 percent for distances predicted from inverting the Baryonic TF (BTF) relation. As TF-based distances (especially the I-band) are relied on heavily for analysis and modeling of the local peculiar velocity (Vpec) field, we suggest that active galaxies be removed from future Vpec modeling samples.

The transition-matrix ($T$-matrix) method has established itself as a prominent technique for computing the scattering response from spatially localized objects. The suitability becomes apparent particularly when considering not just isolated objects but also large ensembles of aperiodically or even periodically arranged objects. A versatile implementation of the method is provided by the treams program, which efficiently computes the electromagnetic response of scatterers in various arrangements [Comput. Phys. Commun. 297, p. 109076 (2024)]. Here, we rely on this framework and present a new program, acoustotreams, dedicated to simulating the acoustic scattering of pressure waves by clusters of particles, both with and without periodic boundary conditions. The computations are performed using the $T$-matrix method with scalar spherical and cylindrical waves as basis sets, and the scattering matrix ($S$-matrix) method in the basis of scalar plane waves for stratified media. The underlying theory is presented alongside the program structure and illustrative examples. The code is open-source and available on the Python Package Index for Linux, Windows, and macOS. Version control is maintained through GitHub, where we also provide automated tests, documentation, and detailed examples. We expect this work to contribute to the field of numerical methods for multiple-scattering problems by offering a computational framework capable of a comprehensive description of pressure-acoustic scattering in artificial media, including well-established metamaterials and metasurfaces.

We introduce OASIS, a simulation-based inference framework for scientific settings where observations are distorted by measurement error, selection effects, and other survey-specific transformations. In many real applications, simulators generate latent, noiseless quantities, while the data are observed only after passing through a complex observational pipeline. Standard simulation-based inference methods often ignore this distinction, comparing observations to idealized simulator outputs or relying on low-dimensional summaries that can miss important structure. OASIS addresses this mismatch by explicitly embedding the observation model into the simulator and performing inference directly at the level of observed-data distributions. The method constructs a pseudo-posterior by reweighting prior samples according to a maximum mean discrepancy (MMD) loss between the empirical distributions of the observed data and forward-simulated observations, thereby avoiding both handcrafted summaries and learned neural surrogates. We provide theoretical guarantees for Monte Carlo consistency, convergence of the empirical pseudo-posterior to its population counterpart, and posterior concentration on the MMD-identified parameter set, with consistency for the true parameter under correct specification and identifiability. In controlled errors-in-variables regression experiments, OASIS delivers robust parameter recovery and well-calibrated uncertainty under heterogeneous and non-Gaussian measurement noise. We then demonstrate the method on a realistic cosmological application involving galaxy cluster observations across multiple wavelengths, in which latent physical properties are linked to observables through nonlinear scaling relations, heteroscedastic errors, selection functions, and incomplete coverage.

Integrated structured-light sources usually obtain high-dimensional orbital angular momentum (OAM) states by encoding each channel into separate gratings, waveguides or metasurfaces, which ties modal capacity to structural complexity. Here we show that intrinsic material anisotropy can instead act as a built-in angular-momentum coupler. In an X-cut thin-film lithium niobate (TFLN) microring vortex emitter, the in-plane optical axis causes a circulating whispering-gallery mode to sample a periodically varying effective index, producing continuous azimuthal phase modulation. This modulation converts each resonance from a nominal single-charge emitter into a coherent topological sideband lattice with charges l=l_p+2n and Bessel-weighted amplitudes. Broadband measurements resolve a representative principal-charge series from l_p=-13 to +13, while additional devices with 100 and 200 GHz free spectral ranges (FSRs) show scalable resonance addressability. The emitted lattices are reproduced by a forward-calculated Fourier–Bessel model, supported by OAM projection measurements, and exhibit focusing into annular perfect-vortex fields and self-healing after obstruction. Waveguide-induced circular polarization further adds a vectorial spin–orbit channel. These results turn TFLN anisotropy from a material constraint into a compact mechanism for resonance-addressed high-dimensional structured-light generation.

We investigate whether embedded stellar-mass black holes (sBHs) in active galactic nucleus (AGN) disks can leave observable optical/UV variability signatures through migration-trap-driven magnetic heating. This mechanism operates when sBHs migrating toward torque-balance radii pile up near migration traps, triggering localized, stochastic magnetic reconnection that heats the disk atmosphere. It is potentially important because it provides a physical source of non-coronal disk heating and directly links optical/UV continuum variability to otherwise hidden compact-object populations. By coupling a one-dimensional sBH population synthesis model with a corona-heated accretion-disk reprocessing variability framework, we show that migration traps concentrate sBHs at preferred radii and generate localized, stochastic reconnection heating. The resulting heating is self-regulated: sBH pile-ups enhance the reconnection rate, while gap opening reduces the local gas density and partially suppresses the reconnection power. This heating produces excess short-timescale optical/UV variability, flattened short-term structure functions, and deviations from the standard $\tau\propto\lambda^{4/3}$ lag-wavelength relation, which describes the time delay between variability at different wavelengths for a standard thin accretion disk. These signatures are strongest at low-to-moderate Eddington ratios, and related observations could provide indirect evidence for embedded compact-object populations in AGN disks.

We study O+O collisions at $\sqrt{s_\mathrm{NN}} = 5.36$ TeV within a fully three-dimensional $\text{McDipper}$+$\text{MUSIC}$ model, which allows us to describe the experimentally measured dependence of charged hadron multiplicity on centrality and pseudorapidity. We show that the initial elliptical eccentricity is mainly driven by the fluctuations of the energy deposition and thereby varies considerably event-by-event within a fixed centrality class. This also holds for elliptic flow $v_2$, whose origin in O+O thus differs from that in collisions of heavy nuclei. Using a decomposition of initial states in an average event and uncorrelated modes, we find that despite the large size of fluctuations we can reproduce the joint probability distribution of eccentricity and elliptic flow with a reasonable accuracy with only a small set of fluctuation modes.

Nonlocal optical nonlinearities arising from the thermorefractive effect provide a long-range material response determined by heat diffusion and absorption. In graded-index media, this nonlocality fundamentally alters modal interactions, yet its accurate modeling remains computationally demanding when starting from the full spatial nonlinear Schrödinger equation. In this work, inspired by the nonpolynomial Schrödinger equation (NPSE) framework, we extend the dimensional reduction techniques to incorporate thermally mediated nonlocal nonlinearities. By coupling the optical field to an equation for the temperature-induced refractive index change, and employing a variational ansatz based on Laguerre–Gauss modes of the annular kind, of arbitrary azimuthal order, we derive explicit analytic expressions for the variational equations. The resulting effective model captures the dependence of the nonlinear interaction on mode order and degree of nonlocality, providing a tractable reduced description of the dynamics in thermal nonlocal media.

The Mpemba effect states that initially hotter systems cool faster than colder ones. While known in convective, conductive, and quantum systems, its radiative analogue is unexplored. Here, this anomaly is realized via phase-change hysteresis of a VO$_2$ nanoparticle near a SiC substrate. After analytically deriving an onset condition, the phase space is mapped. Crucially, latent heat acts as a thermal buffer enabling both ordinary and inverse effects. Near-field coupling governs the relaxation time and enables a passive effect where memory is stored externally via substrate reflection.

An improved formulation of the recently developed cell-centered nodal integral method (MCCNIM) is proposed for the numerical solution of the nonlinear Burgers' equation. The improved scheme, referred to as RCCNIM, reformulates the nonlinear convection term prior to discretization by evaluating the convective velocity using cell-averaged values from the previous time level, rather than the present-time approximation used in the original MCCNIM formulation. This reformulation leads to a fully algebraic system whose coefficients depend only on known quantities and are therefore evaluated once per time step. As a result, the proposed method significantly reduces computational cost while retaining the accuracy of the original MCCNIM. The performance of RCCNIM is assessed through systematic numerical comparisons with MCCNIM for the nonlinear Burgers' equation. The results demonstrate that RCCNIM achieves comparable accuracy with improved computational efficiency, indicating its potential for extension to more complex nonlinear fluid flow problems.

Convection in icy moon oceans is strongly influenced by rotation, organizing into slantwise columnar structures aligned with the planetary rotation axis. They generate significant meridional heat transport, which can affect the ice shell topography, a primary observable of these moons. However, global ocean simulations cannot resolve convection under realistic icy moon conditions, and traditional convection schemes cannot represent slantwise convection. Here, we develop a slantwise convection scheme and implement it in a global ocean model. We perform benchmark tests in a global spherical shell by comparing parameterized fluxes with convection-resolving simulations. The scheme reproduces the meridional heat transport inside the tangent cylinder, where slantwise convection dominates. The resulting meridional heat transport significantly modifies the surface heat flux, producing variations comparable to the imposed bottom heating magnitude. Although the simulations with parameterized convection cannot fully reproduce the temperature structure, likely due to an inability to reproduce the temperature gradients near the boundaries, they capture the bulk interior vertical temperature gradient. The new scheme allows unresolved slantwise convection to be represented in global ocean simulations for icy moons. It is also applicable to other rapidly rotating oceans with small natural Rossby number ($\mathrm{Ro}^* \ll 1$), including deep ocean worlds on exoplanets.

The quantum Hamming bound arises from a direct dimension estimate for exact quantum error-correcting codes. For nondegenerate codes, distinct correctable errors map the code space into orthogonal subspaces, so dimension counting directly gives the bound; degeneracy allows these subspaces to overlap and invalidates the argument. Although linear-programming, asymptotic, and structural approaches have advanced the problem from several directions, the general local-dimension case has remained open. Here we prove the quantum Hamming bound for every local dimension $q\ge3$. Building on the exact two-center Fourier reduction, we develop new overlap estimates for nonbinary Hamming spaces. For $q\ge4$, Jacobi estimates and monotonicity give a uniform gap; qutrits form the boundary case where the gap vanishes and are handled by a filtered correction. This completes the finite-length nonbinary case; together with the existing qubit result, it establishes the quantum Hamming bound for arbitrary local dimension.

Weakly collisional plasmas are widespread in astrophysics and can sustain pressure anisotropy, yet most analytical tearing-mode scalings assume an isotropic equilibrium. We develop a linear theory of resistive tearing in nonideal gyrotropic MHD for a force-free Harris current sheet characterized by perpendicular plasma beta $\beta_0$ and parallel-minus-perpendicular beta difference $\Delta\beta_0$. In the ideal outer region, anisotropy changes the far-field decay rate, the matching parameter $\Delta'$, and the upper wavenumber cutoff for localized tearing, $\alpha\equiv ka<\alpha_c=\sqrt{\mathcal{A}/\mathcal{R}_0}$, with $\mathcal{A}=1-\Delta\beta_0/2$ and $\mathcal{R}_0=1+\frac{1}{2}[(\gamma_\parallel+\gamma_\perp-2)\beta_0+\gamma_\parallel\Delta\beta_0]$. In the resistive inner layer, anisotropy enters the leading momentum balance through $\mathcal{A}$. We derive modified FKR and Coppi branches and, by matching them at their crossover wavenumber, obtain $\gamma_{\max}\tau_A\sim\mathcal{A}^{1/2}\mathcal{R}_0^{-1/4}S^{-1/2}$. Thus the classical Lundquist-number exponent is retained, while the prefactor depends on the equilibrium anisotropy, plasma beta, and gyrotropic closure. PSECAS eigenvalue calculations support the Coppi branch and are consistent with the FKR branch when a fitted finite-wavelength approximation for $\Delta'$ is used. Within the localized-mode and pressure-positive domain, positive $\Delta\beta_0$ generally suppresses tearing and broadens the inner layer, whereas negative $\Delta\beta_0$ enhances growth and shifts the fastest mode to larger wavenumber. This work identifies how prescribed equilibrium pressure anisotropy modifies both ideal outer matching and resistive inner-layer dynamics in the gyrotropic-MHD regime.

We study collisions of domain walls in $SU(N)$ gauge theories using the Polyakov-loop effective potential models. We find that string junctions play a crucial role in the dynamics of $Z_N$ domain walls. In $SU(3)$ gauge theory, the merger of two non-planar $Z_3$ domain walls into a single wall proceeds via the creation of a vortex–antivortex pair in $2+1$ dimensions. In $SU(4)$ gauge theory, low-energy collisions of $Z_4$ walls result in the formation of a single domain wall without the creation of vortices. At higher collision energies, two $Z_4$ domain walls can either bounce back or scatter into another pair of domain walls through the formation of vortices. The creation of vortex–antivortex pairs generalises to the creation of string loops in $3+1$ dimensions for both gauge theories. These results demonstrate a direct dynamical role for topological strings in the evolution of center-domain-wall networks and reveal a new aspect of defect dynamics in non-Abelian gauge theories.

We construct exact timelike junctions between compact flat cavities and a Kinnersley photon-rocket exterior. The shells satisfy the strict surface dominant energy condition and steer subluminally under nonnegative radiation. Burns joined at static spheres give $m_f/m_i=e^{-3L}$ for exterior velocity-space path length $L$; the supported cavity center obeys a separate sharp bound. Self-similar shells require anisotropic stress and have growing normal modes with the ambient geometry and coefficients held fixed. A separate elastic model admits local self-gravitating recoil control with outward emission. At zero gravitational coupling, exact unstrained turns yield sharp fuel bounds and travel limits at fixed duration. Limits on angular concentration and inward emission reduce efficiency. For smooth emission and positive inner-face density, stress-free recoil requires photons to enter the cavity. Self-gravitating settling after a turn remains open.

Liouville pathways provide the conceptual foundation for interpreting multidimensional spectroscopies and are commonly represented as independent contributions to the nonlinear response. In open quantum systems, however, the effective reduced Liouvillian need not preserve this observational pathway decomposition. Environmental interactions can transport amplitude between pathway sectors during the free-evolution intervals, generating measurable signatures in the nonlinear spectroscopic response.} We develop a geometric framework in which pathway transport is governed by a Liouvillian connection, its associated curvature, and the resulting observational holonomy. The framework applies to open quantum systems in which the environment selects a pointer basis distinct from the observational basis used to construct the spectroscopic response. This basis incompatibility induces transport among Liouville pathways, generating characteristic spectral distortions and a nontrivial Liouvillian curvature. Using a Duhamel expansion of the Liouvillian propagator, we derive a reconstruction procedure that identifies the transport operators responsible for the observed redistribution of pathway weight, accurate throughout the full range of basis misalignment. This perspective reframes spectral features as determined not only by which pathways exist but by how amplitude is transported among them. Spectral distortions, peak shifts, and otherwise-forbidden pathway contributions become geometric signatures of a curved Liouville-space manifold rather than phenomenological broadening corrections, identifying pathway geometry as a complementary layer of organization in nonlinear spectroscopy.

Hybrid bright-dark soliton complexes offer profound insights into multi-component nonlinear wave dynamics, yet their systematic generation via artificial saturable absorbers remains unexplored. Here, we experimentally demonstrate a comprehensive hierarchy of higher-order hybrid soliton architectures within a single nonlinear polarization rotation (NPR)-based erbium-doped fiber laser. Continuous tuning of intracavity polarization states and pump power enables reproducible access to soliton structures, with stable mode-locking confirmed at 8 MHz and a signal-to-noise ratio exceeding 72 dB. Cross-phase modulation (XPM)-mediated inter-component coupling and birefringence-induced polarization evolution collectively govern the observed soliton multiplicity, with NPR's inherent tunability proving decisive in accessing higher-order hybrid soliton regimes unexplored in prior studies. These findings expand the fundamental taxonomy of dissipative solitons and establish NPR-based fiber lasers as a reconfigurable platform for complex nonlinear wave engineering.

The 1990-2024 North Atlantic trend in the proportion of major-cyclone Category 3-5 fixes among all Category 1-5 fixes (the Kossin ratio, KR) was about five times the combined Pacific trend. This contrast motivates examining their basin-specific links: aerosol loading to cyclone potential intensity, and potential intensity to observed cyclone activity. Annual increases in aerosol loading were generally associated with decreasing potential intensity both in the North Atlantic and in all three Pacific basins. Potential intensity changes were consistently positively associated with cyclone-fix count changes in the North Atlantic, in some specifications also in the eastern North Pacific and South Pacific. However, changes in potential intensity in the western North Pacific were significantly negatively correlated with fix-count changes. The negative association disappeared after controlling for El Niño-Southern Oscillation changes. Furthermore, annual potential intensity changes were never significantly positively associated with KR changes.

We develop a response-geometric framework for open quantum systems by decomposing the stationary-state response tensor into symmetric and antisymmetric sectors. The symmetric sector defines a metric-like response tensor governing local susceptibility, while the antisymmetric sector defines a curvature two-form associated with nonreciprocal response and geometric work. We show that the work curvature is precisely the antisymmetric component of the response tensor, establishing a fluctuation–response relation that extends the geometric structure of equilibrium thermodynamics to nonequilibrium steady states, and reveals a response geometry with both metric and symplectic sectors. In equilibrium, the antisymmetric sector vanishes by reciprocity, recovering the familiar metric geometry of thermodynamic response. Open quantum systems admit a broader structure in which reciprocal and nonreciprocal responses coexist on the same control manifold. We illustrate this with a driven dissipative qubit under pure dephasing, where finite curvature emerges from the misalignment between the Hamiltonian eigenbasis and the pointer basis selected by the environment, without requiring strong driving or engineered reservoirs. Comparison with the Bures metric shows that response geometry and information geometry characterize distinct properties of the stationary-state manifold: the former governs susceptibility and geometric work, the latter quantifies state distinguishability. Geometric work thus emerges as a measurable signature of nonreciprocal response in open quantum systems.

Quantitative imaging of heat transport with high spatial and temporal resolution is essential for understanding thermal processes in heterogeneous systems, yet direct measurements of transient temperature fields at material interfaces remain challenging. Here, we employ time resolved thermal optical diffraction tomography (thermal ODT), a label free nanoscale optical thermometry technique that reconstructs spatio-temporal evolution of three dimensional temperature fields from thermally induced refractive index changes. We show that thermal diffusion along an interface is controlled by their thermal effusivity contrast. We also derive an effective interfacial diffusivity that accurately describes the lateral propagation of thermal fields and validate the model through finite-element simulations across a broad range of liquid-glass interfaces. Surprisingly, liquids with lower bulk thermal diffusivities exhibit faster interfacial thermal spreading due to their lower effusivities. The measured diffusivities agree quantitatively with theoretical predictions over diverse material combinations. By combining volumetric thermal imaging with a general framework for interfacial heat transport, our work establishes thermal ODT as a powerful platform for investigating nanoscale thermodynamics and engineering heat flow in heterogeneous environments.

We study the effect of subsystem decoherence to an extended cluster state which is a symmetry protected topological (SPT) phase. The model includes many subsystem $Z_2$ symmetries. We report that subsystem decoherence induces local charge fluctuations, leading to a mixed SPT state in the unaffected subsystems. If we start from the extended cluster state, hierarchical mixed-state SPT phases emerge in response to step-by-step subsystem decoherences. These mixed-state SPT phases keep strong symmetries the symmetry of which is protecting symmetries for the initial cluster SPT. Moreover, these SPTs can be characterized by Rényi-2 string orders. Then, as the subsystems are progressively decohered, the hierarchy of mixed-state SPT phases terminates in a $Z_2$ strong-to-weak spontaneous symmetry breaking (SWSSB) state on the final remaining subsystem, where a long-range entangled state appears, namely a glassy Greenberger-Horne-Zeilinger (GHZ) state. Our work demonstrates that decoherence is not merely a destructive process, but can induce and organize series of nontrivial mixed-states. This reveals a systematic route from mixed-state SPT order to SWSSB with the glassy GHZ-type long-range entanglement.

Comprehensive characterization of numerical dissipation is essential for high-fidelity simulations of magnetohydrodynamic (MHD) turbulence. In this work, we present an a posteriori framework for directly estimating numerical dissipation in MHD turbulence from simulation data without invoking a priori assumptions. Implemented in the open-source Python package PyMHD, the framework is applied to simulations of Alfvénic turbulence, turbulent small-scale dynamos, and MRI-driven turbulence, yielding a systematic characterization of the anisotropy and spectral properties of numerical dissipation across these regimes. The results indicate that numerical dissipation primarily dissipates energy transferred by the turbulent cascade at small scales, consistent with the conventional interpretation. However, its spectral properties are distinct from those of physical viscosity and resistivity, such that it cannot simply be represented by effective dissipation coefficients. In addition, numerical dissipation inherits the anisotropy of the underlying turbulence, and can even exhibit anomalous anti-dissipative behavior under certain circumstances. Moreover, this framework enables identification of the conditions under which physical dissipation dominates numerical dissipation across all scales, thereby providing practical guidance for achieving high-fidelity simulations of astrophysical MHD turbulence.

Motivated by recent experimental progress and theoretical developments, we investigate the Cabibbo-favored $b\to c$ governed ${\overline B}_{d,s}$ ${\to}$ $D_{d,s}^{(*)+}S^{-}$~($S$$=$$K_0^*(1430)$, $a_0(1450)$) weak decays by considering the next-to-leading (NLO) contributions within QCDF framework. With the updated values of $B_{(s)}\to D_{(s)}^{(*)}$ transition form factors obtained from a covariant light-front quark model, branching ratios are estimated in two scenarios for scalar mesons. It is found that the branching ratios for ${\overline B}^0{\to}D^{+}{a_0^-}$ and ${\overline B}_{s}^0{\to}D_{s}^{+}{a_0^-}$ decays can reach up to the order of ${\cal O}(10^{-4})$ in scenario-2 by assuming that the scalar mesons are lowest-lying p-wave states, which deserve high-priority experimental searches and may be observed in the ongoing LHCb and SuperKEKB experiments.