Papers

We develop structure-preserving methods for the compressible Euler equations with gravity in vector-invariant form and potential temperature as a prognostic variable within the flux-differencing discontinuous Galerkin spectral element method (DGSEM) framework. By discretizing the nonconservative terms as symmetric and antisymmetric products, we derive two-point numerical fluxes that conserve both the thermodynamic entropy and the total energy. Moreover, we design an entropy-stable numerical flux that is well-balanced for both isothermal and isentropic background states. All properties are shown to carry over to the high-order DGSEM on general curvilinear meshes. Several numerical examples confirm the theoretical findings and show the robustness and accuracy of the scheme for use in modern dynamical cores for atmospheric flows.

Higher-order networks (HONs) represent interactions among groups of objects, supporting the study of collective behaviour that pairwise models can miss. In simplicial models of these networks, Hodge Laplacian linear systems provide a common mathematical framework for analysis, for example, for solving statistical ranking problems and investigating long-term stability in coupled oscillator systems. The large number of variables associated with edges, triangles, and higher-dimensional simplices can make these systems costly to solve. Recent quantum algorithms address this bottleneck. However, comparisons with particular classical algorithms do not decision output whether solving these linear system problems establishes a quantum complexity foundation for provable quantum advantage. We prove that preparing a quantum state encoding the normalized minimum-norm solution of Hodge Laplacian linear systems is $\mathsf{BQP}$-hard under the specified sparse oracle model and parameter promises. Our sequence of reductions maps an arbitrary polynomial-time bounded-error quantum computation to such linear systems. Each reduction allows efficient recovery of the normalized minimum-norm solution of the preceding linear system. Together with an efficient quantum algorithm for the associated decision problem from the approximate solution state, we show that this problem is $\mathsf{BQP}$-complete. These results provide a worst-case complexity foundation for evaluating quantum advantage in HON analysis and show that the $\mathsf{BQP}$-hardness of the quantum linear system problem (QLSP) persists even when the matrices are restricted to Hodge Laplacians.

We investigate static and spherically symmetric black holes in Palatini Kalb-Ramond gravity, where a nonzero vacuum expectation value of the Kalb-Ramond field spontaneously breaks local Lorentz symmetry. Treating the metric and the torsion-free affine connection as independent variables, we derive the modified field equations and obtain an exact family of solutions encompassing positive, vanishing, and negative values of the cosmological constant $\Lambda$. Unlike the corresponding purely metric formulation, the Palatini theory consistently allows both Lorentz-violating parameters $\ell_1$ and $\ell_2$ to be nonzero. Using the Iyer-Wald formalism, we determine the conserved mass of the black hole solutions. For the $\Lambda\leq0$ sector, we further verify the first law and the Smarr relation, identifying the conserved mass as the thermodynamic enthalpy. We then confront the $\Lambda=0$ solution with Mercury's perihelion precession, solar light deflection, and the Shapiro time delay. Once the central mass parameter is calibrated by planetary dynamics, these observables constrain the Lorentz-violating parameters only through $q\equiv\ell_2/(1-\ell_1)$. Among these tests, Mercury's perihelion precession yields the most stringent constraint, $-7.4\times10^{-12} \leq q \leq 3.7\times10^{-11}$.

We investigate whether a minimally coupled Abelian Maxwell sector can relax the Gibbons–Kallosh–Linde (GKL) obstruction to smooth five-dimensional warped braneworlds. For a canonical scalar field coupled to a bulk Maxwell field, we derive the one-parameter family of global consistency conditions while keeping the tangential F_{{\mu}{\nu}} and mixed F_{{\mu}5} sectors separate. This decomposition is essential because the Maxwell stress tensor is not traceless in five dimensions. We show that electromagnetic terms formally modify the integrated GKL constraints, but this modification does not provide a consistent evasion of the no-go theorem under the standard assumptions. Exact four-dimensional Poincaré invariance excludes a nonzero deterministic classical Maxwell field from the background, since its field strength would select preferred four-dimensional directions. The Maxwell sector therefore vanishes in the symmetric background and the usual smooth-brane obstruction is recovered. We also identify which assumptions must be relaxed for a nontrivial electromagnetic contribution and distinguish this background result from local consistency conditions for bulk gauge-field localization.

Among the compact binaries detected through gravitational wave (GW) emission, double neutron stars (DNSs) hold the unique distinction of having well-characterized local analogs in the Milky Way. However, understanding their broader cosmological population remains challenging due to the complex metallicity-dependent evolution of their progenitors. Using the detailed binary population synthesis code POSYDON, we model DNS formation across a cosmological range of metallicities. We find that while DNSs are predominantly formed through common envelope evolution, metallicity-dependent radial expansion and stellar wind mass loss bifurcates the pathway into distinct subchannels, producing systematically distinct merging populations at different metallicities. Notably, our best representative Galactic models predict local merger rates in broad agreement with the latest GWTC-5 constraints, suggesting that the populations observed via radio pulsar surveys and through GW emission need not be in tension. Contrary to previous studies, we demonstrate that the intrinsic merger efficiency increases toward low metallicities, a trend robust across varying binary evolution assumptions, although the magnitude and the underlying stellar processes driving this enhancement vary across metallicity regimes. When convolved with the cosmic star formation history, our models reveal that the majority of merging DNSs originate from progenitors in the range $\sim 0.1\,Z_\odot - Z_\odot$, with significant supersolar contributions. Furthermore, we show that weaker stellar winds at low metallicities produce DNS mergers with systematically more symmetric mass ratios ($q \gtrsim0.9$). Additionally, we assess detectability within proposed configurations for third-generation GW observatories. Our study provides a framework for interpreting the cosmological DNS population in the upcoming multi-messenger era.

Luminous red novae (LRNe) are potential signatures of common envelope evolution (CEE), a critical yet poorly understood phase in compact binary formation. AT 2025abao, an LRN in the Andromeda galaxy, originated from an asymptotic giant branch (AGB) progenitor and exhibited a prolonged pre-outburst transient. Lacking direct constraints on the companion, however, the system's evolutionary fate remains unclear. Here, we unravel the binary nature of AT 2025abao by modeling its complete evolution, from precursor to final outcome. We show that the eight-year infrared precursor arises from a $\approx1.4^{+0.2}_{-0.3}\,M_{\odot}$ main-sequence companion inspiralling through the wind of a $\approx 6.9\,M_{\odot}$ AGB star. As CEE commences, the companion plunges into the envelope and launches a shock. Radiation hydrodynamic modeling of this outburst constrains the total ejecta mass to $\approx 0.92\,M_{\odot}$ and energy to $\approx 1.25\times 10^{47}\,$erg, revealing that only $\approx 0.57\,M_{\odot}$ becomes unbound. Subsequent radiative transfer simulations successfully reproduce the evolving spectral energy distribution. Crucially, our models indicate the main-sequence companion and AGB core survive in an eccentric orbit without merging at least 400 days after CEE onset. AT 2025abao may therefore be the first observed CEE event caught forming a close compact binary, bridging a long-standing observational gap in compact binary formation.

For quantum random number generators (QRNGs), strong security guarantees can be obtained under various assumptions. The most well-known assumptions are the non-signalling assumption (needed for device-independent (DI) QRNG) and post-quantum computational assumptions (needed for computationally bounded single-prover QRNG protocols). In this work, we study a third model: a simple prepare-and-measure QRNG whose security relies on physically motivated energy constraints. This physically motivated set-up allows for easier implementations of QRNGs and can supply better rates. So far, previous works that studied the energy-constrained model either assumed that the adversary is classical in their security proof or supplied relatively weak bounds on the certified randomness, by bounding the conditional min-entropy. In this work, we prove a new, essentially tight, lower bound on the single-round von Neumann entropy against adversaries holding both classical and quantum side-information. Our work reveals that working with the von Neumann entropy, rather than the min-entropy, in the quantum case can lead to a major improvement, nearly matching the classical bound in many cases. We further study the robustness of our entropy bound. Since the single-round von Neumann entropy is the main quantity of interest when characterizing the key rate of QRNGs, our bound establishes the main ingredient for rigorous security proofs against general quantum attacks in this framework.

We show that the expressions for the matter Lagrangian \(L_m\) and the metric variation \(\delta T_{\mu\nu}\) of a perfect fluid obtained in previous studies appear to be inconsistent with the standard energy-momentum tensor under general conditions. Consequently, a large number of studies in astrophysics and cosmology relying on these expressions may need to be re-examined. By performing a series of straightforward calculations directly on the standard energy-momentum tensor \(T_{\mu\nu}\) together with the particle number conservation condition, we derive an expression for \(\delta T_{\mu\nu}\) that is independent of the choice of \(L_m\). Applying this result to \(f(R,T)\) gravity, we obtain the exact form of the tensor \(\Theta_{\mu\nu} = g^{\sigma\rho} \frac{\delta T_{\sigma\rho}}{\delta g^{\mu\nu}}\), which remains an important yet long-standing controversial quantity. This expression is shown to hold also for radiation, regardless of whether particle number is conserved. A major result is that if the energy-momentum tensor \(T_{\mu\nu}\) of the Universe consists solely of standard components (baryonic/cold dark matter, radiation, and the cosmological constant), then \(f(R,T)\) gravity satisfies the conservation law \(\nabla_\mu T^{\mu\nu} = 0\) for any function \(f(R,T)\). This contrasts with previous studies, which found that the conservation law holds only for a restricted class of \(f(R,T)\) functions. Applying the same formalism to stellar interiors, we derive a class of functions that preserve the conservation law. We construct a specific \(f(R,T)\) model that is consistent at both cosmological scales and in high-density objects such as neutron stars. Remarkably, the same parameter set in this model simultaneously alleviates the Hubble tension and reproduces the observed mass-radius (M–R) relation of neutron stars.

Body-body interactions have long been investigated to leverage the performance of various fluid-based machines. This study analyzes the flow interaction between a cylinder and a NACA0012 airfoil using direct numerical simulation and machine learning. We consider a two-dimensional incompressible flow at Reynolds number 100, where the airfoil is positioned in the wake of a cylinder. By sweeping the parameter space, composed of the distance between the cylinder and the airfoil $\Delta x$, the relative height $\Delta y$, and the angle of attack of the airfoil $\alpha$, four characteristic vortex-shedding regimes are observed. This study particularly focuses on suppressed vortex shedding at a certain arrangement as oscillation death in coupled oscillators, with the theoretical prediction of flow stability on a machine-learned low-order coordinate. Independent flows around each body are regarded as a system that exhibits isolated periodic vortex shedding at infinite distance, and interactions appear at smaller distances. We employ a synchronization-theoretic autoencoder to derive models for two coupled oscillators from an aerodynamic coefficient. The proposed approach, which enables the assessment of system stability and the prediction of vortical interaction behavior, may pave the way for the analysis of unsteady body-body interactions from the data-driven and synchronization perspectives.

Transverse optical rectification has been reported in a one-dimensional asymmetric Au grating even though an ideal profile $h(x)$ retains the $xz$ mirror $\Me:y\to-y$. Because $J_y$ is odd under $\Me$, whereas the $p$-polarized bilinears $|E_x|^2$, $|E_z|^2$, and $\mathrm{Re}(E_xE_z^*)$ are even, the transverse dc current requires a distinct mirror-odd factor $\Lamy$. We formulate a symmetry-complete effective model combining the origin-independent cell invariant $\Astr=\mathrm{Im}(h_1^2h_2^*)$, Drude–Edelstein spin polarization, and spin–orbit conversion. We then propose a dynamical realization of $\Lamy$ for a finite-width device. A driven pump-like plasmonic mode at $k_y\simeq0$ generates a mirror pair of transverse surface-plasmon-polariton quasinormal modes $(K_x,\pm q_y)$ through the same third-order susceptibility that produces self- and cross-Kerr shifts. Four-wave mixing creates the pair and locks its phase sum but, by itself, cannot change the pair-population difference. Weak coherent backscattering makes the relative drive phase observable; a small phase difference from incident $k_y$, spot displacement, edges, or disorder then unfolds a Kerr directional instability and deterministically selects its sign. The resulting population imbalance supplies the dynamical mirror-odd factor $\Ldyn=\lambda_\eta\eta$ in the structure-dependent $\Astr\Lamy\langle j_xs_y\rangle_t$ side-jump-like channel, which vanishes for the centered symmetric grating because $\Astr=0$. We give the complete three-mode equations, the pump-only and saturated-state Bogoliubov problems, the imperfect-pitchfork reduction, and a validated normalized numerical realization. The normalized equations exhibit a robust supercritical pitchfork with an approximately one-half critical exponent and phase-reversed branch selection.

We construct the operator product expansions (OPEs) of the ${\cal N}=8$ ${\rm w}_{1+\infty}$ currents (obtained from the antiholomorphic light transform) with the matter fields in the ${\cal N}=8$ supergravity. The corresponding (anti)commutators are obtained from the double contour integrals using the above OPEs. By computing the triple (anti)commutators consisting of current-current-matter (i.e., the Jacobi identity for fixed last element), the previously known ${\cal N}=8$ celestial soft symmetry algebra between these currents (in the antiholomorphic sector) is reproduced. We repeat the above procedure by taking the holomorphic light transform and the OPEs of the ${\cal N}=8$ ${\rm \bar{w}}_{1+\infty}$ currents with the matter fields and the corresponding (anti)commutators are obtained. We also obtain another type of ${\cal N}=8$ celestial soft symmetry algebra between these currents (in the holomorphic sector). As a subalgebra in the antiholomorphic and holomorphic sectors, there exists the ${\cal N}=8$ extended BMS (Bondi, van der Burg, Metzner, and Sachs in 1962) algebra. We analyze the above results from the ${\cal N}=8$ conformally soft ${\rm w}_{1+\infty}$ (or ${\rm \bar{w}}_{1+\infty}$) currents in the antiholomorphic (or holomorphic) sector. The nontrivial soft theorems for the graviton, the gravitinos and the graviphotons are described. Finally, using the shadow transform (the consecutive composition of holomorphic and antiholomorphic light transforms), we obtain the OPEs of the ${\cal N}=8$ shadow ${\rm w}_{1+\infty}$ (or ${\rm \bar{w}}_{1+\infty}$) currents with the matter fields where the stress-energy tensor, the supercurrents and the supertranslation generator of the ${\cal N}=8$ extended BMS algebra are identified.

Consider a quantum state vector proportional to any given column of the character table of the symmetric group ($S_n$), corresponding to a superposition over the irreps weighted by the character values. It was recently argued that sampling from this state is classically hard under reasonable complexity-theoretic assumptions, while there exists an efficient quantum algorithm for preparing this character state using the quantum Fourier transform (QFT) over $S_n$ [arXiv:2501.12579]. We give an alternative, simpler algorithm to prepare this character state with a sequence of Hamiltonian evolutions, as well as an efficient implementation with reconfigurable qubits that uses only nearest-neighbor gates in 1D. The gate complexity, accounting for Hamiltonian simulation errors, depends on the choice of the column: For fixed target state error, the estimated sufficient total gate count ranges from as few as $O(n)$ gates for the $n$-cycle column, to $\widetilde O(n^{1.75})$ gates near the conjecturally classically hard parameter regime, to provably $\widetilde O(n^{2.5})$ gates in the worst case. In contrast, the QFT subroutine in the prior approach uses $\widetilde O(n^3)$ gates. Our gate count estimates come from leading-order state-dependent Trotter error analysis, and the proven worst-case bound relies on a QSVT-based Hamiltonian simulation method; numerical benchmarks of the Trotter-based protocol suggest that the estimates are conservative. Furthermore, we generalize our protocol to give an explicit algorithm for the quantum character transform (QCT) over $S_n$ using $\widetilde O(n^{2.5})$ gates and $O(n)$ qubits. An application to entanglement entropy of symmetric orbifold conformal field theories is also discussed.

Mean-field games provide a continuum framework for modeling the dynamics of large, interacting populations of non-cooperative agents. This paper studies symmetry-breaking in a finite-horizon, two-choice min-LQG mean-field game in which identical agents with linear stochastic dynamics choose one of two equally desirable terminal destinations, while trading off control effort against social pressure to conform. The model has an odd symmetry between the two destinations and therefore always admits a symmetric, dynamic Nash equilibrium in which the population splits evenly between them, producing a deadlock collective state at final time. Numerical studies have suggested that, as the penalty for social nonconformity increases, this symmetric equilibrium loses stability as a fixed point of an associated scalar, self-consistency map, and asymmetric consensus Nash equilibria emerge, where most agents select the same destination. By analyzing the linearized forward-backward PDE system through the scalar map representation, we provide a proof of this loss of stability of the symmetric equilibrium. Together with the odd symmetry of the map, this implies the existence of symmetry-broken mean-field game equilibria corresponding to consensus on either destination.

A cosmological constant $\Lambda$ in a universe weakly violating the cosmological principle (CP) can mimic a dynamical dark energy (DDE) in a FRW universe, and therefore challenging the recently reported DDE evidences. We test this scenario in the form of $\Lambda$LTB cosmology, against two data combinations. (1) DESI DR2 BAO, Planck CMB, together with any of the four SNe Ia compilations (UNION3, Pantheon+, DES SN5YR, and DES Dovekie) show no preference over DDE or $\Lambda$LTB. (2) The inclusion of the kinematic Sunyaev Zel'dovich (kSZ) effect rules out a large portion of the CP violation parameter space allowed by (1). However, the existence of a $\sim 300$ Mpc$/h$ region with $\sim 10\%$ matter density excess is still allowed by the current data, and therefore remains a viable alternative to DDE. To facilitate further tests, we present analytical expressions of the distance-redshift relation and the kSZ effect in a universe with weak CP violation.

We examine the role of the Bakamjian–Thomas (BT) construction in achieving current-component independence for pseudoscalar-to-pseudoscalar semileptonic form factors in light-front (LF) dynamics. An exactly solvable covariant Bethe–Salpeter (BS) model provides an off-shell benchmark. Its transverse-current zero-mode contribution is calculated directly from the shrinking nonvalence region and reproduced by an effective operator in the valence convolution. In the BT-based LF quark model, the one-body current kernel is constructed from on-shell constituent spinors, while interactions are encoded in the mass operator and wave functions. In this realization, the $(+,\perp)$ current-component extraction is zero-mode free and is saturated by the on-shell overlap. Using the free constituent invariant masses consistently in the internal projections yields the same $f_-(q^2)$ from the $(+,\perp)$ and $(+,-)$ current-component extractions after integration. We establish this equality analytically for rotationally invariant radial wave functions with the LF Jacobian and the adopted pseudoscalar spin coupling, provided the reduced overlaps converge. The difference from the minus-current projection using physical meson masses defines an interaction-dependent BT completion, distinct from the BS endpoint contribution. A mass-weighted complex transverse contour permits direct evaluation of the Gaussian $D\to K$ overlaps throughout the physical timelike interval, including zero recoil, without a form-factor parametrization or extrapolation. These results establish current-component independence within the specified BT realization and clarify the dynamical dependence of zero-mode assignments.

We investigate the mass spectra and two-body nonleptonic weak decays of ground-state doubly and triply heavy baryons in a nonrelativistic quark-diquark model. To account for the finite size of the diquark, we generalize the convoluted quark-diquark interaction to unequal-mass diquarks using mass-weighted constituent coordinates and distinct pairwise spin-spin couplings. The resulting Schrödinger equations provide the baryon masses and wave functions used consistently in the decay calculation. The predicted masses differ from existing lattice QCD results by less than $1.5\%$, and our calculated mass of $\Omega_{cc}^{+}$ is consistent with recent LHCb observations. The calculated hyperfine splittings are systematically slightly smaller than the lattice values, indicating a residual uncertainty in the spin-dependent interaction. Within the factorization approximation, we evaluate the $c\to s$ and $b\to c$ transitions with pion or kaon emission. At leading nonrelativistic order, the vector contribution vanishes for the $3/2^+\to1/2^+$ transitions, while both vector and axial contributions enter the $3/2^+\to3/2^+$ channels. The $b\to c$ spatial overlaps are substantially smaller than their $c\to s$ counterparts. Together with the Cabibbo-Kobayashi-Maskawa hierarchy, this reduces the corresponding $b \to c$ width by approximately two orders of magnitude. In the $3/2^+\to1/2^+$ charm transitions, the leading $|\bm{k}|^3$ dependence enhances the suppression of kaon emission. In bottom transitions with a larger energy release, the smaller relative phase-space difference brings the ratios close to the scaling determined by the Cabibbo-Kobayashi-Maskawa elements and meson decay constants. These results provide benchmark estimates for future studies of multiply heavy baryons and quantify the role of recoil dynamics within the finite-size quark-diquark framework.

Thermal X-ray pulse-profile modeling depends on the angular and spectral properties of neutron star atmosphere emission. We construct a compact empirical approximation to the specific intensity using eight coefficients for the angular dependence and five for a normalized spectral kernel. The angular prescription is motivated by the formal solution of the radiative-transfer equation, while the spectral normalization preserves a specified bolometric flux. We calibrate this family to numerical atmosphere tables, focusing on return-current-heated and fully ionized hydrogen atmospheres. When incorporated into a semi-analytic pulse-profile model, the approximation reproduces profiles normalized by their phase-averaged flux to within approximately $4\%$ for antipodal hot spots and $5\%$ for non-antipodal hot spots in the tested heated-atmosphere configurations. We also analyze synthetic eXTP observations using different beaming prescriptions to test the conclusion in our previous work based on a linear description of the angular dependence of the emission. The comparisons suggest that the angular dependence of the intensity cannot be simply characterized by a linear function of the cosine value of the emission angle, because its detailed shape and energy dependence will affect the parameter inference. This parameterization can significantly increase the efficiency for analytic and numerical models, and provide a compact framework for examining how atmosphere assumptions affect neutron star pulse profiles and the inferred stellar properties.

It has been known that (the square of) Jacobi elliptic function can be expressed by an infinite sum of single solitons of $\sech^2$ shape. In this paper, we show that there exists a similar structure for higher genus cases. It turns out that this is just a consequence of the quasi-periodicity of the Riemann $\theta$-function. More precisely, we show that the second derivative of $\log \theta$ with the real Riemann $\theta$-function of genus $g$ near soliton limit can be well approximated by the sum of real and regular $g$-soliton solutions of Hirota-type in $g$-dimensional real space $\R^g$. This leads to a tessellation of $\R^g$, whose tile is an oblique prism divided into $2^g$ sections by hyper-planes of dominant exponents in the theta function. We apply the results to study quasi-periodic solutions to the KdV and KP equations. We construct the quasi-periodic solutions using the Schottky group, which uniformizes the corresponding Riemann surfaces. We also discuss solitons on quasi-periodic background by pinching some of the homological cycles

The emergence of spin-polarized electrons from nonmagnetic chiral molecules and crystals is called Chirality-induced spin selectivity (CISS). A chiral phonon of definite wavevector $q$ can strongly enhance it, but near equilibrium the two helicities $+q$ and $-q$ are equally populated: they are time-reversal partners and their contributions cancel. We show that in a biased chiral conductor the current causes the phonon of one helicity to damp less than the other. The damping asymmetry is odd in the current, odd under $q\rightarrow-q$, invariant under a mirror that reverses the structural handedness, and equal, mode for mode, to the current-induced nonconservative Berry force on the phonon coordinate. Closing the phonon kinetics with a rate equation turns the asymmetry into a net lattice helicity: at any finite bias one helicity is preferentially populated, with no threshold, growing linearly with the current as $V\rightarrow0$; above a threshold that helicity becomes a self-sustained coherent travelling wave. We demonstrate this effect in elemental tellurium, treated as an open quantum system (electronic Hamiltonian, phonon bath, and electron-phonon coupling) within a quasi-ab initio framework. The electronic Hamiltonian is supplied by a vertex-corrected quasiparticle self-consistent $GW$ (QSGW) potential with spin-orbit coupling; nuclear displacements are modeled with a machine-learned interatomic potential, which yields chiral phonon modes at finite $\pm q_z$ on the $\Gamma$-A line. The perturbation to the electronic Hamiltonian from a nuclear displacement is approximated by a frozen-phonon deformation potential. No optical pump is needed: a bias alone drives the current and selects the phonon helicity; reversing the current reverses the selection.

The nonlinear Hall effect (NLHE) holds significant promise for next-generation electronic device applications, and it is essential to explore and engineer a strong and highly tunable NLHE. In this work, we report large second-order and third-order NLHEs in dual-gated BiSbTeSe2 devices. Both the second-order and third-order NLHE are highly gate-tunable. The second-order NLHE exhibits a higher generation efficiency than those reported in previous topological insulator systems, and it can be stably observed up to room temperature. Meanwhile, the generation efficiency of the third-order NLHE is comparable to previously reported values. The scaling analysis indicates that the second-order NLHE is consistent with contributions from skew scattering and a term compatible with either the Berry curvature dipole or side jump, whereas the third-order NLHE is consistent with contributions from the Berry connection polarizability tensor and higher-order skew scattering. Our work establishes a promising experimental platform for the development of NLHE-based devices.

For two decades, the origin of Chirality-Induced Spin Selectivity (CISS), the spin polarization of electrons by nonmagnetic chiral systems without magnetic fields, has remained unsettled. Here, we establish a single exact rule defining the fundamental conditions for the effect: in nonmagnetic, time-reversal-invariant conductors, all measurable CISS signals are time-reversal odd and vanish near equilibrium, proving that structural chirality alone is insufficient. By evaluating leading theoretical mechanisms across four levels of nonequilibrium transport, from coherent classical driving to fully non-Markovian quantum baths, we verify this selection rule to machine precision. We show that coherent chiral vibrations generate substantial collinear polarization (up to 10 percent across 0.5-6 THz) that reverses with handedness, whereas incoherent vibrations yield under 1 percent, and non-Markovian bath memory further suppresses the signal. The chiral geometry first makes the electronic motion chiral by accumulating orbital angular momentum; spin-orbit coupling (SOC) then converts that into spin. CISS therefore acts as both a spin polarizer and a spin filter, the latter an order of magnitude weaker. The polarization grows with molecular length and then saturates, matching trends reported for DNA and peptides. Reversing the drive converts decaying spin into a handedness-locked charge-current pulse (inverse-CISS). We find that once the system is driven, the polarization magnitude scales with an effective spin-orbit coupling: making heavy atoms and curved light-atom backbones indistinguishable at equivalent effective SOC. This enables us to chart how geometry, driving field, and length separate those routes.

A quantum-classical correspondence for non-Hermitian symmetry breaking has recently been established using coordinate-space path integrals, providing a semiclassical understanding of spectral transitions at the level of individual eigenstates. Here we develop its dual formulation in momentum space by constructing the corresponding trace formula and quantization condition. We show that the real or complex nature of individual eigenvalues is determined by the symmetry properties of the associated semiclassical orbits, as in the coordinate-space path-integral approach. Moreover, we demonstrate that the topology of semiclassical orbits determines the natural formulation of the quantization condition: the coordinate- and momentum-space formulations are equivalent for contractible periodic orbits in phase space, whereas for noncontractible orbits, the quantization condition along the winding direction remains valid, but its dual form must be corrected by a boundary term. In particular, real-space-winding and Brillouin-zone-winding orbits naturally select coordinate- and momentum-space quantization, respectively. As a nontrivial application, we investigate the boundary-induced spectral transition of Bloch oscillations in a finite non-Hermitian lattice, where Bloch-oscillation orbits winding across the Brillouin zone preserve the relevant symmetry and yield real energy levels, whereas boundary-reflected orbits form symmetry-related pairs and give rise to complex-conjugate eigenvalues. Our work completes the quantum-classical correspondence framework for non-Hermitian symmetry breaking, extending its applicability to a broader class of non-Hermitian problems.

Groups of individuals can solve collective problems more accurately than any single member, by aggregating their opinions. Recent theoretical work has identified individual-level reward schemes that allow uninformed individuals to evolve collective intelligence from the bottom up, through social learning. Yet these results are restricted to linear prediction problems and simple averaging, while the decision tasks that real groups confront are often non-linear, and the institutions that aggregate opinions are seldom single-layer averages: districts elect representatives who in turn vote on policy, referees advise editors who decide on publication. Here we develop a framework for the evolution of collective intelligence in multi-layer voting populations, where individuals observe limited information and groups recursively aggregate their opinions by majority rule. We prove that single-layer voting cannot solve non-linear classification problems under any individual reward scheme. We then identify a "marginal feedback" payoff structure, which rewards individuals only when their opinion is pivotal in their group, and at every layer above them. This reward scheme induces a layered population to evolve accurate collective solutions to complex, non-linear decision tasks through individual-level peer imitation alone. The collective behavior that emerges is equivalent to a multi-layer perceptron in machine learning. Our results provide a naturalistic account of hierarchical institutions, in which the outsize importance of swing voters is the incentive that sustains collective accuracy; and they identify the credit-assignment rule in machine learning as not just an engineered solution but a natural evolutionary outcome.

Communication using quantum channels generally requires encoding and decoding on many identical uses of a quantum channel. In practical settings, decoherence may severely limit our ability to do so, potentially rendering each channel use nonidentical. Given $n$ nonidentical channels, we present an entanglement-assisted encoding and decoding strategy that yields a channel with higher worst-case fidelity than all of the $n$ given channels. The strategy is universal, in the sense that the improvement holds regardless of what channels are given, as long as they satisfy mild assumptions on their initial entanglement fidelities. Our protocol is optimal when the given channels are depolarizing channels, and is essentially the unique one that is universal. This idea can also be extended to classical channels, where shared randomness between the sender and the receiver allows universal enhancement of the probability of correct transmission. We then consider general quantum resource theories, providing a necessary condition and a sufficient condition for the possibility of such universal improvement of quantum resources.

A series of 11.6-d-duration photon-counting experiments, employing a broad variety of light sources with different statistical properties and optical spectra, were carried out over a 1.5-yr period. All of the photon-count spectra at baseband followed a common $1/f^2$ form over the frequency range $1 \times 10^{-6} \leqslant f \leqslant 5 \times 10^{-4}$ Hz, corresponding to a timescale range $33$ min $ \leqslant T_f \leqslant 11.6$ d, where $T_f \equiv 1/f$. The lower and upper timescale limits were established by the photodetector noise floor and the duration of the individual experiments, respectively. Unlike ordinary Brownian motion, all of the measured photon-count sample paths exhibited irregular long-timescale fluctuations, with durations ranging from hours to days. It has been established that the photon-count spectra cannot plausibly be ascribed to fluctuations of the current, voltage, or temperature of the source or the detector, nor to technical sources of noise associated with the optical system or local environment. Although the physical origin of the photon-count fluctuations remains unresolved, several heterodox hypotheses are set forth. From a statistical point-of-view, the photon counts appear to follow a doubly stochastic Poisson process with a slowly varying random intensity. Analogous experiments that rely on ionizing radiation and direct-conversion solid-state radiation detectors are proposed.

We develop a Bayesian generalization of the previous method to constrain a wide variety of mass-concentration (M-C) relations motivated by both theoretical and observational studies. The framework incorporates the intrinsic scatter in concentration, nonlinear weak-lensing (WL) calibration relations, the WL measurement-error covariance, and the underlying parent mass distribution. We employ Hamiltonian Monte Carlo for computational efficiency. Our sample consists of 213 X-ray-selected clusters with WL measurements for the eRASS1, XXL, LoCuSS, and MCXC catalogs at 0<z< 0.9. For each subsample, we account for its specific WL calibration relation and underlying population distribution. We consider a conventional single power-law model, an empirical double power-law model, and four theoretical models calibrated against numerical simulations. The four theoretical M-C models comprise two in which concentration decreases with mass, distinguished by the sign of d^2ln c/d(ln M)^2, and two in which the concentration decreases with increasing mass before turning upward at high masses. Because the mass and redshift ranges of our cluster sample do not extend into the upturn regime predicted by numerical simulations, we distinguish among the models primarily through the curvature of their M-C relations. Regardless of which model is adopted, the inferred M-C relation is in good agreement with the results of recent numerical simulations. We find no statistically significant differences among the models above the $4\sigma$ level. However, the result shows a tendency toward a gradual flattening of the mass dependence toward higher masses. Specifically, a monotonically decreasing model with positive curvature is preferred over the single power-law relation and a monotonically decreasing model with negative curvature at the $2\sigma$ level and over three double power-law models at the $0.5-1\sigma$ level.

Global magnetohydrodynamic (MHD) simulations provide the complete plasma state of the heliosphere, but their computational cost limits applications requiring repeated model evaluations. We introduce SNOW (Solar Neural Operator for Wind), a fast and differentiable surrogate for global MHD solar wind. SNOW combines a rotational ballistic approximation, a spherical harmonic neural operator, and causal radial context to autoregressively propagate all eight MHD variables from 20 to 240 Rs through consecutive shell to shell transitions. Trained and evaluated using AWSoM simulations spanning a solar cycle, SNOW remains stable across the complete rollout. The model successfully reproduces the large scale plasma and magnetic field structures, including fast and slow wind streams, magnetic polarity sectors, vector orientations, fieldline connectivity, and bulk-flow structures. Additionally, the magnetic divergence and induction diagnostics remain comparable to the reference MHD solutions. The complete three-dimensional solution is generated in less than one second on a single GPU. These results demonstrate the feasibility of fast neural emulation of global MHD solar wind solutions while retaining physically meaningful plasma and magnetic field structure.

We construct an exact NUT-charged generalization of the Ellis-Bronnikov wormhole in the Einstein-phantom-scalar system. The solution is stationary, asymptotically locally flat at both ends and free of curvature singularities. It inherits characteristic features of the Taub-NUT geometry, including the Dirac-Misner string and closed timelike curves, while the absence of Killing horizons eliminates the horizon-induced infinite winding of geodesics and renders the spacetime geodesically complete. By allowing the phantom field to have a nontrivial scalar potential with an infinite sequence of AdS vacua, we also obtain an exact asymptotically locally AdS wormhole with a NUT charge, which interpolates between different vacua at its two asymptotic ends. Using the covariant phase space formalism, we show that the Hamiltonian charges associated with the two asymptotic regions are finite under appropriate scalar boundary conditions. By performing a double Wick rotation to Euclidean signature, we demonstrate that the conformal class of the resulting metric admits an ambi-Kähler structure.

Self-consistent mean-field calculations with semi-realistic interactions have predicted that $N=58$ becomes a magic number near Ni, where the $n2s_{1/2}$ orbit is the highest occupied state. As the last neutrons occupy the shallowly bound $s$-orbit, $^{86}$Ni can be highly distinctive, being a doubly-magic nucleus and possessing a neutron halo simultaneously. With minimal ambiguity in the many-body wave function, it may provide a unique opportunity to investigate, e.g., reaction mechanisms in halo nuclei. As an example, we present differential cross sections for proton elastic scattering predicted via a folding potential without local approximations, and compare them with those obtained using an empirical potential.

The Lindblad master equation is the standard framework for describing the non-unitary evolution of open quantum systems, where environmental interactions induce dissipation and decoherence. When both the system Hamiltonian and the dissipation rates are partially unknown or explicitly time-dependent, traditional analytical inversion and system-identification techniques become intractable. Recent works have demonstrated that Transformer-based models can infer unknown dissipation rates from observable time series, yet these approaches typically rely on hand-crafted statistical features under idealized and highly restricted conditions. Here we advance the paradigm by introducing a raw time-series Transformer that directly ingests the full trajectories of Pauli expectation values $\langle\sigma _x(t)\rangle$, $\langle\sigma _y(t)\rangle$, and $\langle\sigma_z(t)\rangle$, thereby fully exploiting the self-attention mechanism for temporal modeling. The architecture is further extended to jointly learn unknown Hamiltonian parameters, handle multiple dissipation channels, and operate robustly under realistic measurement noise. Across all tested scenarios the model achieves consistently high reconstruction accuracy while eliminating manual feature engineering. This provides a scalable, robust, and versatile framework for quantum environment sensing in realistic open quantum systems.