Let $M$ be a holomorphically symplectic manifold, equipped with a Lagrangian fibration $π:\; M \to X$. A degenerate twistor deformation (sometimes also called ``a Tate-Shafarevich twist'') is a family of holomorphically symplectic structures on $M$ parametrized by $H^{1,1}(X)$. All members of this family are equipped with a holomorphic Lagrangian projection to $X$, and their fibers are isomorphic to the fibers of $π$. Assume that $M$ is a compact hyperkahler manifold of maximal holonomy, and the general fiber of the Lagrangian projection $π$ is primitive (that is, not divisible) in integer homology. We also assume that $π$ has reduced fibers in codimension 1. Then $M$ has a degenerate twistor deformation $M'$ such that the Lagrangian projection $π:\; M' \to X$ admits a meromorphic section.

Moiré superlattice in two-dimensional (2D) materials provides a powerful platform to engineer emergent electronic states, yet the construction of moiré superlattices remains lab-scale, involving much trial and error and with little control. Here, we demonstrate the construction of a heterostrain-induced moiré superlattice in transition metal dichalcogenides using a scalable process that deterministically induces strain to 2D materials. By applying patterned thin-film stressors and probing the resulting structures with scanning transmission electron microscopy, we directly resolve the induced heterostrain, lattice deformations, and stacking variations that produce the moiré superlattice. We find that uniaxial and biaxial heterostrain give rise to distinct moiré patterns, including stripes and distorted hexagonal patterns. With this approach, we create in-plane polar distortions and thus in-plane polarization at the domain boundaries of the moiré superlattice in MoS$_2$. The deterministic and scalable construction of moiré patterns using a well-established scalable process opens opportunities to design new moiré geometries in 2D materials.

Little Red Dots (LRDs) are a new class of compact extragalactic objects, with a v-shaped optical spectral energy distribution breaking close to the Balmer break wavelength, and broad, typically exponentially-shaped lines. They are believed to be supermassive black holes surrounded by very dense, ionized gas, leading us to explore for any departures from Case B recombination by examining the ratios of multiple hydrogen Balmer lines: $Hα$, $Hβ$, $Hγ$, and $Hδ$. We analyze a dozen high-S/N LRDs with JWST/NIRSpec, measuring Balmer ratios in the seven objects with coverage of at least three lines. We decompose the line ratios into their respective broad and narrow components. Broad line ratios are consistent with Case B plus dust extinction in all objects but one, RUBIES EGS-49140, which departs from Case B expectations by more than $5σ$. The narrow components are consistent with minimal dust attenuation, while two objects exhibit narrow $Hα$/$Hβ\approx 1.8$. Such low decrements are observed in highly ionized density bounded nebulae, associated with starburst environments. Nevertheless, both flat decrement cases can be reconciled assuming an unresolved absorption feature. RUBIES EGS-49140, shows a high broad $Hα$/$Hβ$, but $Hγ$/$Hα$ and $Hδ$/$Hα$ ratios are lower than expected for extinction-modified Case B, hinting at an unphysically steep dust law. These line ratios may be due to increased optical depth in the Balmer lines, as a direct effect of high density (log$n_e$ > 9) gas surrounding the black hole. If Case B recombination does hold in most LRDs, they must be moderate-to-heavily dust obscured ($A_V\simeq1-8$) while the host-galaxy should be dust-free, suggesting that the extinction in the broad lines is local to the LRD and not due to the general ISM of the host galaxy.

A fixed set of vertices in the plane may have multiple planar straight-line triangulations in which the degree of each vertex is the same. As such, the degree information does not completely determine the triangulation. We show that even if we know, for each vertex, the number of neighbors in each of the four cardinal directions, the triangulation is not completely determined. In fact, we show that counting such triangulations is #P-hard via a reduction from #3-regular bipartite planar vertex cover.

Cold dark matter (CDM) can be thought of as a 2D (or 3D) sheet of particles in 4D (or 6D) phase-space due to its negligible velocity dispersion. The large-scale structure, also called the cosmic web, is thus a result of the topology of the CDM manifold. Initial crossing of particle trajectories occurs at the critical points of this manifold, forming singularities that seed most of the collapsed structures. The cosmic web can thus be characterized using the points of singularities. In this context, we employ catastrophe theory in 2D to study the motion around such singularities and analytically model the shape of the emerging structures, particularly the pancakes, which later evolve into halos and filaments-the building blocks of the 2D web. We compute higher-order corrections to the shape of the pancakes, including properties such as the curvature and the scale of transition from their C to S shape. Using Gaussian statistics (with the assumption of Zeldovich flow) for our model parameters, we also compute the distributions of observable features related to the shape of pancakes and their variation across halo and filament populations in 2D cosmologies. We find that a larger fraction of pancakes evolve into filaments, they are more curved if they are to evolve into halos, are dominantly C-shaped, and the nature of shell-crossing is highly anisotropic. Extending this work to 3D will allow testing of predictions against actual observations of the cosmic web and searching for signatures of non-Gaussianity at corresponding scales.

Phases manifesting topological patterns in functional systems, like ferroelectric and ferromagnetic vortex superlattices, can manifest intricate and apparently ungovernable behavior, typical of frustrated non-ergodic states with high-dimensional energy landscapes. This is also the case for potassium-tantalate-niobate (KTN) crystals. These transparent ferroelectrics manifest remarkable but little-understood metastable domain patterns at optical (micrometer and above) scales near the cubic-to-tetragonal structural phase transition. Here, we formulate the Topological Breakdown Model based on the competition between intrinsic scales of domain-domain collinear and non-collinear interactions associated with polarization-charge screening. The model is able to explain observed KTN mesoscopic domain patterns and phase diagram as a function of temperature and external electric field. Findings include a precise set of sharp and broad percolative transitions that are experimentally verified, validating our model. Our study identifies the central role played by competing topologically protected states, identifying a fundamental link between topological protection and frustration that supports a hitherto unexplored functional non-ergodic arena.

Emergent collective excitations constitute a hallmark of interacting quantum many-body systems, yet in solid-state platforms their study has been largely limited by the constraints of linear-response probes and by finite momentum resolution. We propose to overcome these limitations by combining the spatial resolution of ultracold atomic systems with the nonlinear probing capabilities of two-dimensional spectroscopy (2DS). As a concrete illustration, we analyze momentum-resolved 2DS of the quantum sine-Gordon model describing the low energy dynamics of two weakly coupled one-dimensional Bose-Einstein condensates. This approach reveals distinctive many-body signatures, most notably asymmetric cross-peaks reflecting the interplay between isolated ($B_2$ breather) and continuum ($B_1$ pair) modes. The protocol further enables direct characterization of anharmonicity and disorder, establishing momentum-resolved 2DS as both a powerful diagnostic for quantum simulators and a versatile probe of correlated quantum matter.

Describing Li-ion battery positive electrodes in terms of distinct transition metal or oxygen redox regimes can lead to confusion in understanding metal-ligand hybridisation, oxygen dimerisation, and degradation. There is a pressing need to study the electronic structure of these materials and determine the role each cation and anion plays in charge compensation. Here, we employ transition metal L-edge X-ray Resonance Photoemission Spectroscopy in conjunction with Single Impurity Anderson models, Self-consistent Real Space Multiple Scattering spectral simulations, and Dynamical Mean-Field theory calculations to directly evaluate the redox mechanisms in (de-)lithiated battery electrodes. This approach reconciles the redox description of two canonical cathodes -- LiMn$_{0.6}$Fe$_{0.4}$PO$_{4}$ and LiNiO$_{2}$ -- in terms of varying degrees of charge transfer using the established Zaanen-Sawatzky-Allen framework, common to condensed matter physics. In LiMn$_{0.6}$Fe$_{0.4}$PO$_{4}$, the absence of charge transfer means capacity arises due to the depopulation of metal $\textit{3d}$ states, i.e. conventional metal redox. Whereas, in LiNiO$_{2}$, charge transfer dominates and redox occurs through the formation and elimination of ligand hole states. This work clarifies the role of oxygen in Ni-rich system and provides a framework to explain how capacity can be extracted from oxygen-dominated states in highly covalent systems without needing to invoke dimerisation.

Classical nucleation theory predicts size-dependent nucleation and melting due to surface and confinement effects at the nanoscale. In correlated electronic states, observation of size-dependent nucleation and melting is rarely reported, likely due to the extremely small length scales necessary to observe such effects for electronic states. Here, using 1T-TiSe$_2$ nanoflakes as a prototypical two-dimensional (2D) charge density wave (CDW) system, we perform in-situ cryogenic electron microscopy with temperature down to 20 K and observe size-dependent nucleation and melting of CDWs. Specifically, we observe a melting point depression of CDW for 1T-TiSe$_2$ flakes with lateral sizes less than 100 nm. By fitting experimental data to a Ginzburg-Landau model, we estimate a zero-temperature correlation length of 10--50 nm, which matches the reported CDW domain size for 1T-TiSe$_2$. As the flake size approaches the correlation length, the divergence of the CDW correlation length near the transition is cut off by the finite flake size, limiting long-range order and thereby lowering the transition temperature. For very small flakes whose size is close to the correlation length, we also observe absence of CDWs, as predicted by the model. We thus show that an electronic phase transition follows classical nucleation theory.

The Cosmic Distance Duality Relation (CDDR) is a fundamental principle of standard cosmology, linking luminosity (LD) and angular diameter distances (ADD). This work investigates the validity of the CDDR and cosmic transparency by combining the latest Baryon Acoustic Oscillations (BAO) data from DESI DR2, Type Ia Supernovae from Pantheon+, and cosmic chronometers. To address the redshift mismatch between datasets, two distinct reconstruction techniques are employed: Gaussian Process Regression (GPR) and the Free-Knots Method (FKM). The analysis performs null tests on the CDDR under different cosmological priors, finding that the null hypothesis holds and the CDDR is valid within statistical uncertainties. Although mild deviations are observed from the local distance ladder prior, internal consistency calibration indicates that these discrepancies and the Hubble tension may share a common origin, possibly related to systematic effects or new physics. Using multiple phenomenological parameterizations, the deviation parameter is also found to be statistically consistent with zero (e.g., $η_1 = 0.023 \pm 0.027$ for the linear model under Planck priors). Furthermore, the study finds no statistically significant evidence for cosmic opacity. The average of the opacity derivative is compatible with zero ($\langle dτ/dz \rangle = 0.0409 \pm 0.1024$ for GPR and $0.0730 \pm 0.1607$ for FKM). Based on these null results, stringent constraints are placed on the parameter space of Axion-Like Particles (ALPs) and Mini-Charged Particles (MCPs).

Lattice relaxation profoundly reshapes electronic structures in twisted materials. Prevailing treatments, however, typically rely on large-scale density functional theory (DFT), which is computationally costly and mechanistically opaque. Here, we develop a unified analytical framework to overcome these limitations. From continuum elastic theory, we derive closed-form solutions for both in-plane and out-of-plane relaxation fields. We further introduce an analytical phase factor expansion theory that maps relaxation into the electronic Hamiltonian. By applying this framework, the relaxation-mediated single-particle and many-body topological phase transitions in twisted MoTe$_{2}$ is accurately captured, and the evolution of flat bands in magic-angle graphene is quantitatively reproduced. Our work transforms the research of moiré relaxation from black-box numerical fitting to an analytical paradigm, offering fundamental insights, exceptional efficiency, and general applicability to a wide range of twisted materials.

Reconfigurable integrated chips of photonic components and networks are envisaged to play a key role in realizing highly efficient integrated photonic information processing. Electrothermally modulated optical effect (ETMOE) is a powerful thermo-optic tuning mechanism for silicon photonic devices, enabling precise optical control via localized Joule heating. We present a rigorous and three-dimensional electronic-photonic co-integrated approach with the nonlinear numerical coupling of temperature and wavelength-dependent material properties to comprehensively model ETMOE in silicon waveguides and resonators. A platinum-based symmetric heater is optimized using advanced true 3D numerical simulations, achieving efficient ETMOE-based tuning while mitigating asymmetric heat distribution. In addition to a complete design and analysis of the fully integrated three-dimensional switch, we also evaluate single-mode waveguide cutoff, heater-to-waveguide separation, heater dimensions, and thermal dissipation, providing a framework for ETMOE-based optimization. The findings contribute to energy-efficient, programmable photonic systems for neuromorphic computing, optical interconnects, and reconfigurable photonic networks.

Ranking athletes by their performance in competitions and tournaments is common in every popular sport and has significant benefits that contribute to both the organization and strategic aspects of competitions. Although rankings are perhaps the most concise and most straightforward representation of the relative strength among the competitors, beyond this one-dimensional characterization, it is also possible to capture the relationships between athletes in greater detail. Following this approach, our study examines the networks between athletes in individual sports such as tennis and fencing, where the nodes are associated with the contestants and the edges are directed from the winner to the loser. We demonstrate that the connections formed through matches arrange themselves into a time-evolving hierarchy, with the top players positioned at its apex. The structure of the resulting networks exhibits detectable differences depending on whether they are constructed purely from round-robin data or from purely elimination-style tournaments. We find that elimination tournaments lead to networks with a smaller level of hierarchy and thus, importantly, to an increased probability of circular win-loss situations (cycles). The position within the hierarchy, along with other network metrics, can be used to predict match outcomes. In the systems studied, these methods provide predictions with an accuracy comparable to that of forecasts based on official sports ranking points or the Elo rating system. A deeper understanding of the delicate aspects of the networks of pairwise contests enhances our ability to model, predict, and optimize the behaviour of many complex systems, whether in sports tournaments, social interactions, or other competitive environments.

Organisms use specialized sensors to measure their environments, but the fundamental principles that determine their accuracy remain largely unknown. In Escherichia coli chemotaxis, we previously found that gradient-climbing speed is bounded by the amount of information that cells acquire from their environment, and that E. coli operate near this bound. However, it remains unclear what prevents them from acquiring more information. Past work argued that E. coli's chemosensing is limited by the physics of molecules stochastically arriving at cells' receptors, without direct evidence. Here, we show instead that E. coli are far from this physical limit. To show this, we develop a theoretical approach that uses information rates to quantify how accurately behaviorally-relevant signals can be estimated from available observations: molecule arrivals for the physical limit; chemotaxis signaling activity for E. coli. Measuring these information rates in single-cell experiments across multiple background concentrations, we find that E. coli encode two orders of magnitude less information than the physical limit. Thus, E. coli chemosensing is limited by internal noise in signal processing rather than the physics of molecule diffusion, motivating investigation of what specific physical and biological constraints shaped the evolution of this prototypical sensory system.

The morphology and kinematics of atomic Hydrogen (HI) gas in galaxies are influenced by both local and large scale cosmic environments. Differences in galaxy environment and interactions can leave distinct signatures in HI asymmetry, offering insight into environmental effects on galaxy evolution. We investigate the role of environment on HI asymmetries in galaxies located in two contrasting structures: the Ursa Major (UMa) group and the Perseus Pisces (PP) filament. We analyze HI 21cm imaging from the WSRT and the VLA, homogenized in resolution for fair comparison. Asymmetries in global profiles and column density maps are measured using criteria established in arXiv:2205.00675 and compared to those of mock galaxies presented in the same study. The PP volume hosts a higher fraction of galaxies with asymmetric global HI profiles (33%) compared to UMa (9%). Likewise, 46% of PP galaxies have morphological HI asymmetries above 0.5 at a threshold of 15 x 10^19 cm^-2, compared to 13% in UMa. The greater column density sensitivity of the UMa data enables detection of lopsided features and asymmetry measurement down to 5 x 10^19 cm^-2. We also identify simulated galaxies with unphysical asymmetries likely caused by unrealistic feedback. In both volumes, stellar and HI morphological asymmetries are uncorrelated. Global profile and morphological asymmetries are also found to be uncorrelated, consistent with previous results.

The linear Edelstein effect is a cornerstone phenomenon in spintronics that describes the generation of spin magnetization in response to an applied electric field. Recent theoretical advances have reignited interest in its nonlinear counterpart, the nonlinear Edelstein effect, in which spin magnetization is induced by a second-order electric field. However, the intrinsic contribution to both effects is generally forbidden in systems preserving time-reversal symmetry ($\mathcal{T}$) or composite symmetries such as $\mathcal{T}τ_{1/2}$, where $τ_{1/2}$ denotes a half-lattice translation. In such systems, spin magnetization typically emerges either from extrinsic mechanisms but limited to metals due to their Fermi-surface property, or from dynamical electric fields with a terahertz driving frequency. Here, we propose a new mechanism for spin magnetization, arising from the interplay of magnetic and electric fields, termed the nonlinear magnetoelectric Edelstein effect. Remarkably, its intrinsic component, determined purely by the material's band structure, can appear even in $\mathcal{T}$-invariant materials, but lacking inversion symmetry ($\mathcal{P}$), including insulators. On the other hand, we illustrate that its extrinsic component can serve as a sensitive indicator of the Néel vector reversal in $\mathcal{P}\mathcal{T}$-symmetric antiferromagnetic materials, offering a novel route for antiferromagnetic order detection. To validate our theory, we perform explicit calculations using a two-band Dirac model and a tight-binding model on a honeycomb lattice, finding that both effects yield sizable spin magnetization. Our findings establish the nonlinear magnetoelectric Edelstein effect as a versatile platform for both exploring nonlinear spin physics and enabling symmetry-based detection of antiferromagnetic order.

Phase field simulations play a key role in the understanding of microstructure evolution in additive manufacturing. However, they have been found extremely computationally expensive. One of the reasons is the small time step requirement to resolve the complex microstructure evolution during the rapid solidification process. This paper investigates the possibility of using a class of stabilized time integration algorithms to accelerate such phase field simulations by increasing the time steps, based on a phase field model dedicated to simulating the solidification of 316L stainless steel during additive manufacturing, particularly in a regime where the solid-liquid interface is moving fast and there is absolute interfacial stability with negligible composition variations. The specific computational framework, incorporating the finite element method and the stabilized time integration algorithms, was developed. A theoretical analysis on energy stability was conducted, based on a revisited energy law derived for the phase field model. The numerical results confirmed that the proposed framework can effectively enforce the numerical stability and a decreasing energy requirement for the phase field simulations with at least two orders-of-magnitude larger time steps over conventional explicit methods. 2D and 3D phase field simulations have been conducted with relevant physical and kinetic parameters for 316L stainless steel. This computational framework can be easily adapted for different phase field models and open numerous opportunities for efficient phase field simulations.

The intracluster medium (ICM), composed of hot plasma, dominates the baryonic content of galaxy clusters and is primarily observable in X-rays. Its thermodynamic properties, pressure, temperature, entropy, and electron density, offer crucial insight into the physical processes shaping clusters, from accretion and mergers to radiative cooling and feedback. We investigate the thermodynamic properties of galaxy clusters in the Simulating the LOcal Web (SLOW) constrained simulations, which reproduce the observed large-scale structure of the local Universe. We assess how well these simulations reproduce observed ICM profiles and explore the connection between cluster formation history and core classification. Three-dimensional thermodynamic profiles are extracted and compared to deprojected X-ray and Sunyaev - Zel'dovich (SZ) data for local clusters classified as solid cool-core (SCC), weakly cool-core (WCC), and non-cool-core (NCC) systems. We also examine the mass assembly history of the simulated counterparts to link their formation to present-day ICM properties. The simulations reproduce global thermodynamic profiles for clusters such as Perseus, Coma, A85, A119, A1644, A2029, A3158, and A3266. Moreover, they show that CC clusters typically assemble their mass earlier, while NCC systems grow through more extended, late-time merger-driven histories. WCC clusters show intermediate behavior, suggesting an evolutionary transition. Our results demonstrate that constrained simulations provide a powerful tool for linking cluster formation history to present-day ICM properties and point to possible refinements in subgrid physics as well as in resolution that could improve the agreement in cluster core regions.

We present the numerical methods, programming methodology, verification, and performance assessment of a non-equilibrium plasma fluid solver that can effectively utilize current and upcoming central processing and graphics processing unit (CPU+GPU) architectures, in this work. Our plasma fluid model solves the coupled conservation equations for species transport, electrostatic Poisson and electron temperature on adaptive Cartesian grids. Our solver is written using performance portable adaptive-grid/particle management library, AMReX, and is portable over widely available vendor specific GPU architectures. We present verification of our solver using method of manufactured solutions that indicate formal second order accuracy with central diffusion and fifth-order weighted-essentially-non-oscillatory (WENO) advection scheme. We also verify our solver with published literature on capacitive discharges and atmospheric pressure streamer propagation. We demonstrate the use of our solver on two 3D simulation cases: an atmospheric streamer propagation in Ar-H2 mixtures and a low pressure twin electrode radio frequency reactor. Our performance studies on three different CPU+GPU architectures indicate approximately 150-400X speed-up using AMD and NVIDIA GPUs per time step compared to a single CPU core for a 4 million cell simulation with 15 species.

We present a scalable framework for accurately modeling many-body interactions in surface-code quantum processor units (QPUs). Combining a concise diagrammatic formalism with high-precision numerical methods, our approach efficiently evaluates high-order, long-range Pauli string couplings and maps complete chip layouts onto exact effective Hamiltonians. Applying this method to surface-code architectures, such as Google's Sycamore lattice, we identify three distinct operational regimes: computationally stable, error-dominated, and hierarchy-inverted. Our analysis reveals that even modest increases in residual qubit-qubit crosstalk can invert the interaction hierarchy, driving the system from a computationally favorable phase into a topologically ordered regime. This framework thus serves as a powerful guide for optimizing next-generation high-fidelity surface-code hardware and provides a pathway to investigate emergent quantum many-body phenomena.

Time-evolving perforated domains arise in many engineering and geoscientific applications, including reactive transport, particle deposition, and structural degradation in porous media. Accurately capturing the macroscopic behavior of such systems poses significant computational challenges due to the dynamic fine-scale geometries. In this paper, we develop a robust and generalizable multiscale modeling framework based on multicontinuum homogenization to derive effective macroscopic equations in shrinking domains. The method distinguishes multiple continua according to the physical characteristics (e.g., channel widths), and couples them via space-time local cell problems formulated on representative volume elements. These local problems incorporate temporal derivatives and domain evolution, ensuring consistency with underlying fine-scale dynamics. The resulting upscaled system yields computable macroscopic coefficients and is suitable for large-scale simulations. Several numerical experiments are presented to validate the accuracy, efficiency, and potential applicability of the method to complex time-dependent engineering problems.

One of the major goals of modern nuclear experiments is to study the distributions of gluons inside nuclei at high energy. A key measurement is the coherent exclusive vector meson (VM) production in diffractive electron-nucleus collisions, where the gluon spatial distribution inside the nucleus can be obtained through a Fourier transform of the squared nuclear momentum transfer ($|t|$) distribution. This research aims to overcome the two main obstacles of the $|t|$ measurement: limited precision in measuring $|t|$ arising from the momentum resolution of the outgoing electron and the overwhelming incoherent background. We demonstrate that by measuring the projected $|t|$ distribution along the direction perpendicular to the electron scattering plane, the effect of the outgoing electron's momentum resolution can be effectively mitigated, and the diffractive pattern is largely restored. Furthermore, we propose to measure the angular distribution of the VM's decay daughters to statistically remove the incoherent background.

Recently, an intriguing correspondence was conjectured in arXiv:2409.11551 between Schur half-indices of pure 4d $SU(2)$ $\mathcal{N}=2$ supersymmetric Yang-Mills (SYM) theory with line operator insertions and partition functions of the double scaling limit of the Sachdev-Ye-Kitaev model (DSSYK). Motivated by this, we explore a generalization to $SU(N)$ $\mathcal{N}=2$ SYM theories. We begin by deriving the algebra of line operators, $\mathcal{A}_{\text{Schur}}$, representing it both in terms of the $\mathfrak{q}$-Weyl algebra and $\mathfrak{q}$-deformed harmonic oscillators, respectively. In the latter framework, the half-index admits a natural description as an expectation value in the Fock space of the oscillators. This $\mathfrak{q}$-oscillator perspective further suggests an interpretation in terms of generalized colored chord counting, and maps the half-index to a purely combinatorial quantity. Finally, we establish a connection with the quantum Toda chain, which is an integrable model whose commuting Hamiltonians can be identified with the Wilson lines of the $SU(N)$ SYM, and their eigenfunctions correspond to the function basis appearing in the half-index.

We propose a probabilistic approach to modeling catalog incompleteness through four candidate augmented Gutenberg-Richter (GR) laws, which incorporates incompleteness into the frequency-magnitude distribution (FMD) using two parameters, mc, the transition magnitude, and σc, which defines the transition range from incompleteness to completeness. The four GR models are tested on synthetic and empirical catalogs, using multiple performance evaluation metrics. The GR-AEReLU model, which allows for an asymmetry in the convergence to the pure linear GR law for m > mc relative to the censorship of earthquakes of sizes smaller than mc, is found to consistently outperform, providing more robust estimates of seismological parameters (e.g., b-value) that better reflect realistic physical conditions and observational characteristics. This augmented framework offers three main advantages: (1) unified modeling of incompleteness into the FMD, (2) parameters with clear physical and statistical meaning, and (3) the ability to capture nonlinear and asymmetric detection behaviors. Finally, our analysis reveals systematic regional variations in earthquake b-values that deviate significantly from the assumed universal value of 1.0, challenging a fundamental paradigm in seismology and demonstrating the need for region-specific values that reflect local tectonic conditions in seismic hazard assessments.

Revealing the nature of the nanoHz gravitational wave (GW) signal recently reported by Pulsar Timing Arrays (PTAs) collaborations around the world is the next goal of low-frequency GW astronomy. The signal likely originates from the incoherent superposition of GWs emitted by a cosmological population of supermassive black hole binaries (SMBHBs). Those binaries can be highly eccentric and/or strongly coupled to their nuclear environment, resulting in an attenuation of the overall GW signal at low frequencies. In this paper, we propose to use the correlation properties of the distributed GW power in the sky across the frequency spectrum as a smoking gun for eccentric SMBHBs thus allowing to break the spectral degeneracy between eccentricity and environmental effect. The simple underlying idea is that, contrary to circular binaries, eccentric ones emit a broadband spectrum thus resulting in similar sky maps at different frequencies. We first demonstrate the applicability of this simple concept on sky maps constructed directly from the theoretical sky distribution of the GWB power induced by realistic populations of SMBHBs. We then demonstrate the viability of this analysis on simulated SKA-like PTA data. By statistically comparing sky maps reconstructed from hundreds injected circular and highly eccentric SMBHB populations, we find that eccentricity can be detected at $3σ$ in more than $50\%$ of cases.

The multisymplectic Hamiltonian formalism is a generalization of the Hamiltonian formalism that manifestly preserves covariance in the description of fields and that has been proposed as a possible framework for developing a Lorentz-covariant, canonical quantization scheme. However, the possibility of defining multiple Poisson brackets within this formalism has significantly limited its practical use in field theory. In this paper, we establish a connection between the Lagrangian and multisymplectic descriptions of classical fields interacting with point particles in the field's momentum representation by deriving the image of the de Donder-Weyl function for a general tensor representation of the Lorentz group. The calculation is carried out explicitly for the complex scalar field, the electromagnetic field, and the classical Dirac field. On this basis, we propose a Lorentz-covariant Poisson bracket with respect to the canonical variables of the fields, thereby opening the possibility of studying the complete system within a consistent relativistic and canonical framework.

JWST and HST observations have revealed numerous elongated, pickle-shaped galaxies at high to intermediate redshifts, with masses close to those expected for Milky Way progenitors. Here we use reduced-mass eigentensors to quantify the ellipsoidal shape evolution of thirteen Milky Way-mass galaxies simulated using FIRE-2 physics; all but one form disks at $z=0$. We find that all of our Milky Way progenitors go through phases when they are elongated. They often oscillate between spheroidal and elongated shapes in the early Universe over billion-year timescales. This is true whether we measure shapes weighted on stellar mass or luminosity, though the luminosity shapes show more extreme elongation and variance. In contrast, the stellar populations of our $z=0$ Milky Way analogs are never elongated and always symmetric about their minor axes. The youngest stars at $z=0$ reside in thin disks, intermediate-age stars reside in thick disks, and the oldest stars reside in flattened spheroids that are symmetric about their minor axes. Despite their symmetric shapes at $z=0$, the old and intermediate age stellar populations were often arranged in the shape of elongated pickles or triaxial spheroids at the time they formed, meaning that these populations changed shape significantly over time. Our results suggest that observed elongated galaxies seen in the early Universe are not stable structures, but rather reflect transitory phases of galaxy evolution.

Future hadron collider experiments will require sensing materials that withstand stronger radiation fields. Therefore, either a frequent replacement of detectors, a significant increase in radiation hardness of Silicon, or a shift to different materials is needed. Wide-bandgap materials are a natural choice, due to their significantly reduced leakage currents, even after irradiation. In recent years, substantial progress in the production of high-quality monocrystalline Silicon Carbide of the 4H polytype has led to a renewed interest in this material. In this article, a study of electrically active defects in a n-type epitaxial 4H Silicon Carbide diode is presented. By employing spectroscopical measurement methods, like Deep-Level Transient Spectroscopy (DLTS) and Thermally Stimulated Currents (TSC), energy levels in the bandgap are investigated. Defect parameters like concentration, activation energy and capture cross-section are stated. A simulation framework was utilised to compare and match the results from the two methods. This study is made in the context of a study of radiation hardness of 4H Silicon Carbide sensors. Other studies investigating macroscopic properties of the material, like their charge collection efficiency after irradiation, were performed on the same kind of diodes. This study provides a first set of measured defect parameters in state-of-the-art 4H-SiC material, from defects present prior to irradiation. These defects are intrinsic, such as vacancies, related to impurities and doping imperfections, or are growth related. The $Z_\text{1/2}$ defect and a Nitrogen related defect were identified.

For lc algebraically integrable foliations on klt varieties, we prove the base-point-freeness theorem, the contraction theorem, and the existence of flips. The first result resolves a conjecture of Cascini and Spicer, while the latter two results strengthen a result of Cascini and Spicer by removing their assumption on the termination of flips. Moreover, we prove the existence of the minimal model program for lc algebraically integrable foliations on klt varieties and the existence of good minimal models or Mori fiber spaces for lc algebraically integrable foliations polarized by ample divisors on klt varieties. As a consequence, we show that $\mathbb{Q}$-factorial klt varieties with lc algebraically integrable Fano foliation structures are Mori dream spaces. We also show the existence of a Shokurov-type polytope for lc algebraically integrable foliations.

The mid-infrared spectral range holds great promise for applications such as molecular spectroscopy and telecommunications. Many key molecules exhibit strong absorption features in this range, and free-space optical communication benefits from reduced atmospheric attenuation and low transmission losses in specific wavelength bands spanning from 3 to 14 $μm$. Recent progress in MIR photonics has been fuelled by the rapid development of efficient light sources and detectors. However, further advancement is hindered by the lack of low-loss, high-performance integrated photonic platforms and modulators. Lithium niobate on sapphire is a promising candidate, operating across a broad spectral range from 0.4 $μm$ to 4.5 $μm$. We demonstrate a broadband, high-speed lithium niobate on sapphire Mach-Zehnder electro-optic modulator operating from 3.95 to 4.3 $μm$. The device achieves a 3 dB bandwidth exceeding 20 GHz, an extinction ratio of 34 dB, and a half-wave voltage of 22 V$\cdot$cm, delivering optical output power at the half-milliwatt level. These properties are leveraged to demonstrate data transmission at 10 Gbit/s. The modulator is also used to generate a frequency comb with a width of 80 GHz. Furthermore, we demonstrate full $π$-phase modulation in the MIR, representing a key milestone for integrated MIR photonics. These results establish a pathway toward high-speed, energy-efficient MIR photonic systems for applications in telecommunications, sensing, and quantum technologies.