Papers

One can distinguish four major formulations of the Bloch-mode problem in linear periodic media. First, there are two common complementary ways of slicing the Bloch variety (Bloch wave vectors paired with the corresponding frequencies): frequency vs. wave vector or, conversely, wave vector vs. frequency. This paper deals exclusively with the latter option, directly applicable to lossy media, evanescent waves, and complex band structures. A separate crossroads is the full field (FF) vs. the lattice-periodic Bloch factor (PF) formulations. These are fully equivalent on the continuous level, but common discretization techniques may break this equivalence not just approximately but qualitatively. In the FF problem, the primary unknown eigenvalue is the Bloch phase factor (not the wavenumber), which enters only through opposite-boundary coupling. The PF formulation, on the other hand, injects the Bloch wavenumber into the differential operator and leads to a volume quadratic pencil. Consequently, standard PF discretizations of the type considered here, in contrast with the corresponding FF discretizations, violate the reciprocal-lattice (Brillouin-zone-shift) covariance – which, as the theory and numerical examples in the paper show, may lead to inaccurate or even nonphysical modes. From the mathematical perspective, the paper highlights the role of structure-preserving algorithms. The practical importance of the results and recommendations stems from the wide adoption of PF formulations in optics, photonics, and beyond – such as the computation of propagating and evanescent Bloch modes in photonic and acoustic structures, topological photonics, effective-mass and topological insulator band theories.

For a spin-zero meson, the exact trace identity relates the D term to the tensor gravitational form factor $A_M(t)$ and the total scalar trace $\Theta_M(t)$. We study the pion and kaon D terms by combining a holographic tensor form factor with a chiral-dispersive representation of the trace. Its normalization and slope at the origin are obtained from the forward Ward identity and curved-space SU(3) chiral perturbation theory. A two-channel $\pi\pi/K\bar K$ Muskhelishvili–Omnès solution constructed from empirical scattering amplitudes describes the continuation to spacelike momentum. Available lattice-QCD results are shown for comparison. In the chiral limit, saturation of the trace by the normalized explicit quark-mass response gives $D_\pi(0)=-1/3$, while the soft-pion theorem gives $D_\pi(0)=-1$. This comparison separates the explicit-mass contribution from the remaining chiral scalar response. At physical masses, SU(3) breaking in the chiral matching distinguishes the pion and kaon forward values, and coupled-channel rescattering governs their evolution away from the origin. The kaon D term is less negative than the pion result in the low-$Q^2$ spacelike region considered, with the separation decreasing as $Q^2$ increases. These form factors provide a low-energy reference for future lattice studies of the tensor and scalar channels.

We investigate the long-time behavior of optimal mixing in an advection-diffusion equation using a shell model framework. Our focus is on quantifying the decay of the scalar variance, measured by the negative Sobolev norm $H^{-1}$, under enstrophy-constrained stirring. We perform long-time computations using both local-in-time (maximizing the instantaneous mixing rate) and global-in-time (maximizing mixedness at a prescribed final time) optimization strategies. For mixing with diffusion ($\kappa>0$), the numerical results show that the scalar length scale eventually becomes limited by a generalized Batchelor scale, in close agreement with theoretical predictions. In this regime, the $H^{-1}$ mix-norm decays exponentially in time with a decay rate that is independent of the diffusivity $\kappa$. Compared with the purely advective case ($\kappa = 0$), diffusion significantly enhances the long-time mixing rate; moreover, increasing diffusivity further improves mixing efficiency by reducing the prefactor of the exponential decay. Guided by these numerical observations, we derive new conditional lower bounds on the $H^{-1}$ norm whose exponential decay rates are strictly independent of the diffusivity parameter $\kappa$, for all $\kappa > 0$. We further establish conditional upper bounds on the maximal rate of enhanced dissipation of the scalar variance, showing that the effective diffusion time scale is at least of the order $|\log\kappa|$.

In this article a piece of the reference time-dependent density-functional response theory (TDDFRT) representation of molecular electronic transitions is studied through the one-body reduced difference density matrix. A first derivation route for that object has been reported in the literature based on the substitution of TDDFRT-related objects into an exact functional expression. We show in the text that the functional providing the exact object is not unique, and we question whether substituting the same TDDFRT-related objects into the alternative functional expressions leads to acceptable candidates for the approximate TDDFRT one-body reduced difference density matrix, which would question the unequivocality of the TDDFRT representation of molecular electronic transitions. We first directly address the problem using a novel diagrammatic language, inspired by Dyck languages, and specifically designed for dealing with this kind of issue. In the last part of the article we question whether it is possible or not to recast the problem in a more general framework - the equations-of-motion framework. Through all the text, the case of time-dependent Hartree-Fock is compared with that of TDDFRT to highlight what makes them so different when those questions are at stake.

Cavity-mediated collective-spin interactions are commonly described by a quadratic one-axis twisting Hamiltonian. However, the underlying atom-light interaction naturally generates nonlinearities to arbitrary order. Here, we derive a closed-form analytical expression for the complete hierarchy of cavity-mediated collective-spin interactions. We show that the nonlinear coefficients $\chi_k$ are governed by Chebyshev polynomials, with $k$ the order of nonlinearity. This yields a universal scaling $\chi_k\propto\eta^k$ with the single-atom cooperativity $\eta$ and a description of their dependence on cavity detuning. The result provides a systematic framework for determining when higher-order nonlinearities become relevant and when the quadratic approximation breaks down. We identify experimentally relevant regimes in which higher-order terms substantially modify collective-spin dynamics, accelerating the generation of quantum correlations and quantum Fisher information, and demonstrate that finite-order expansions can accurately reproduce the full cavity-mediated evolution. Our results establish a general framework for understanding higher-order nonlinearities in cavity quantum electrodynamics and their role in collective entanglement and quantum-enhanced sensing.

We compute for the first time the subleading twist correction to the exclusive rare $b \to \left \{s, d \right \} \ell^{+} \ell^{-}$ decays from the three-particle $B$-meson distribution amplitude at next-to-leading order accuracy by employing the soft-collinear effective theory. This constitutes the last missing ingredient for the complete factorization analysis of the hadronic matrix element of the weak effective Hamiltonian at leading power in the heavy quark expansion. Incorporating further a variety of the next-to-next-to-leading-order QCD corrections to the spectator-scattering amplitude and the weak annihilation topology, we then present the improved field-theoretic predictions for phenomenologically interesting observables in the electroweak penguin $B \to \left \{K, \pi \right \} \ell^{+} \ell^{-}$ decays.

We study optimal control problems for incompressible fluids in two-dimensional domains with a cold boundary and internal heat sources and sinks. Given a kinetic energy budget, measured by the square of a nondimensional Péclet number $\mathrm{Pe}$, the goal is to maximize a cooling efficiency inversely proportional to the mean square gradient of the fluid's temperature. Using Lagrange duality, we formulate a well-posed dual problem whose solution yields an upper bound on the maximum cooling efficiency $\mathcal{E}(\mathrm{Pe})$. We then numerically approximate the dual problem using a convergent hierarchy of semidefinite programs obtained via discretization. We illustrate this computational approach on optimal cooling problems in a square and in an annulus, explaining also how problem symmetries can be exploited to reduce computational complexity. Finally, we construct admissible points for the dual problem to obtain new analytical upper bounds on the optimal cooling efficiency $\mathcal{E}(\mathrm{Pe})$. Specifically, we prove that $\mathcal{E}(\mathrm{Pe}) \lesssim \mathrm{Pe}^{2}$ for arbitrary domains and heat distributions, and that $\mathcal{E}(\mathrm{Pe}) \lesssim \mathrm{Pe}^{2}/ \ln^2\mathrm{Pe}$ for cooling flows in disks and annuli with heat source/sink distributions with a uniformly positive azimuthal average. These results generalize and improve known efficiency bounds for energy-constrained cooling flows in a disk.

The relationship between cryptography and learning theory has long been a central theme in the foundations of theoretical computer science: cryptographic primitives can imply hardness of learning, while hardness of learning can in turn be used to construct cryptographic schemes. Recent works have begun exploring analogous connections in the quantum setting, relating the average-case hardness of learning quantum states (AHL) to cryptographic primitives such as one-way state generators (OWSG). Despite recent progress exploring this for pure states, the relationship for mixed states has remained an open question. In this work, we prove that the existence of AHL for mixed quantum states is equivalent to the existence of inefficiently verifiable one-way state generators (IV-OWSGs). As a consequence, this relates mixed-state AHL to EFI pairs. Moreover, as a corollary of existing results, we obtain a separation between IV-OWSGs and OWSGs relative to the SWAP oracle.

A projective measurement of a many-body state produces a microscopic snapshot, usually viewed as random classical data. We show that partial occupation snapshots of the critical XX chain contain a universal angle with a precise conformal meaning. Dividing the ring into two measured and two unmeasured arcs, we assign geometry-dependent conformal side weights to the observed occupations and obtain a compact variable $\delta_L$. At every finite size, $\delta_L$ is fixed by the measured sites alone; the particular complete-configuration lift $X_L$ used in the proof additionally depends on unobserved particles. This angle is an exact microscopic compact coordinate whose scaling-limit law is that of the relative Dirichlet phase of the associated conformal quadrilateral—the boundary coordinate conjugate to charge in continuum post-measurement descriptions. Exact free-fermion determinants yield all of its Fourier moments. We prove that the lift becomes Gaussian with variance $2h(\zeta)$, where $h(\zeta)$ is the rectangle modulus, and hence $\langle e^{\ii q\delta_L}\rangle\to e^{-h(\zeta)q^2}$. Thus raw quantum snapshots realize the heat kernel on a circle and provide an outcome-level microscopic foundation for the compact zero-mode sector of Born averages over fluctuating conformal boundary conditions.

We show that geometric phases accumulated during adiabatic evolution can be converted into observable interference in Krylov space, leading to a geometric-phase-dependent Krylov oscillation. Adiabatic dynamics force Krylov complexity to vanish if the initial Krylov basis is an instantaneous eigenstate of the Hamiltonian; Nevertheless, we demonstrate that the Krylov complexity will be non-vanishing if the initial Krylov basis is a superposition state rather than an eigenstate. Consequently, Krylov complexity is found to depend on the difference of dynamical phases in the Krylov space, which is deeply related to the Berry connections in the original Hilbert space. In particular, for a single qubit system with constant Lanczos coefficients, Krylov complexity oscillates harmonically at a frequency given by the strength of the external field and the geometric Berry phase. Therefore, our work may provide a novel avenue to probe the geometric phase from the Krylov complexity.

We study quantum multi-armed bandits (QMAB) and quantum linear bandits (QLB), where the learner queries each arm or action through a quantum reward oracle or its inverse. Prior work gives algorithms over horizon $T$ with regret $O(K\log T)$ for QMAB with $K$ arms and $O(d^2\operatorname{polylog} T)$ for $d$-dimensional QLB. This leaves open the optimal dependence on $K$ and $T$ and whether the dependence on $d$ can be further improved. In this work, we prove the first tight minimax regret bound of $\Theta(K\log(1+T/K))$ for QMAB and the first lower bound of $\Omega(d\log(1+T/d))$ for finite-action QLB, ruling out regret independent of $T$. Our lower bounds rely on a high-confidence single-arm quantum testing lower bound for distinguishing a fixed reward mean from an interval of alternatives. A bandit-to-testing reduction then lifts it to the QMAB lower bound, while a linear embedding gives the finite-action QLB lower bound. The matching QMAB upper bound is obtained using a tail bound for the Quantum Monte Carlo (QMC) estimator. For finite-action QLB, we propose a phased elimination algorithm that combines a low-bias low-variance quantum mean estimator with a small-support $G$-optimal design through a query allocation matched to the design weights. When the action set has size $\operatorname{poly}(d)$, its regret is nearly linear in $d$ and matches our lower bound up to polylogarithmic factors.

Top-up injection is required in FCC-ee to maintain high luminosity given the short beam lifetime. The present baseline relies on on-axis off-energy injection with a conventional orbit bump; in this work, an alternative on-axis scheme based on a multipole injection kicker (MIK) is investigated. The FCC-ee beam parameters place challenging demands on the MIK field distribution, which must combine a large field-free region for the circulating beam, a narrow transition region, and a sufficiently uniform field in the injection region across all operation modes. To relax these challenging requirements while limiting the residual kick on the circulating beam, a compensated MIK scheme is proposed, in which a compensation MIK (CMIK) is placed upstream of the main MIK, and the required optics and field-symmetry conditions between the two devices are derived for different phase advances. The pulsed-conductor kicker is adopted as the preferred design, and its influence on the circulating beam and its injection performance are evaluated for the Z operation mode. In the Z mode, the near-zero phase-advance compensated scheme limits the single-pass emittance growth of the circulating beam to about $7\%$ horizontally and below $2\%$ vertically, while the injected beam requires transfer-line pre-compensation to mitigate the field gradient in the injection region. These results indicate that compensated MIK injection is a promising candidate for FCC-ee on-axis top-up injection.

The immersed boundary (IB) method models fluid–structure interaction using the natural Lagrangian and Eulerian formulations of structural mechanics and fluid dynamics, respectively, but explicit time discretization of the IB force imposes a stiffness-dependent upper bound on the time-step size. Treating these forces implicitly removes this restriction, but the resulting coupled linear systems become increasingly difficult to solve as the structural stiffness increases. Algebraically eliminating the Lagrangian degrees of freedom yields a reduced Eulerian velocity–pressure IB system. Here we introduce a coupling-aware Vanka (CAV) smoothing strategy to enable effective multigrid preconditioning of this system. CAV patches are built as unions of standard pressure-centered Vanka patches, with the graph of the Eulerian elasticity matrix determining which patches are combined. Under grid refinement, CAV patch sizes remain bounded, and the computational cost of each multigrid cycle thereby grows linearly with the number of Eulerian degrees of freedom. Tests using target-point, membrane, and beam force laws show that CAV-preconditioned FGMRES reduces the relative residual by ten orders of magnitude in $9--15$ iterations, with little growth under grid refinement. In a nonlinear benchmark modeling flow past a flexible fiber, the average number of FGMRES iterations per Newton solve increases only from $8.6$ to $9.5$ as the Eulerian grid is refined from $32\times32$ to $256\times256$ cells. To our knowledge, CAV provides the first robust multigrid strategy for time-dependent implicit IB formulations.

We study score-matching diffusion models with a convolutional architecture. We argue that the inductive bias of locality means that the machinery of effective field theory from physics can be usefully applied to describe the denoising dynamics. We apply this formalism first to a simple toy example which permits an analytical description, and thereafter to MNIST, and show that in both cases, the mutual information between two points grows in a manner predicted by a simple effective field theory of Brownian motion.

The search for materials with multifunctional properties has attracted significant attention due to their potential applications in various energy-related devices. Pressure-induced phase transitions provide an effective strategy for accessing different structural phases of a material without altering its chemical composition, thereby enabling the tuning of its physical properties and expanding its functional applications. In this work, we investigate the previously unexplored orthorhombic (Pnma) phase of the KMgX (X = P, As, Sb, and Bi) family using first-principles calculations and identify a pressure-induced structural transition from a tetragonal to orthorhombic phase. Stability of the pressure-accessible orthorhombic structure is rigorously confirmed by equation of state analysis together with phonon, elastic, and formation-enthalpy calculations, establishing its viability for further investigation. Optical properties calculated within the $G_0W_0$-Bethe-Salpeter equation (BSE) framework, incorporating quasiparticle corrections and excitonic effects, exhibit direct dipole-allowed transitions at the $\Gamma$ point and strong visible-light absorption with coefficients approaching $10^5~\text{cm}^{-1}$. Consequently, KMgAs and KMgSb achieve spectroscopic limited maximum efficiencies (SLME) of $27.12\%$ and $26.40\%$, respectively, at a thin-film thickness of $0.6~\mu\text{m}$. Furthermore, thermoelectric transport calculations predict (zT) values of 0.65 and 0.58 at $900~\text{K}$ for p-type and n-type KMgSb, respectively, demonstrating its potential for both legs of thermoelectric devices. These values are likely conservative, as the Slack model tends to overestimate thermal conductivity. Overall, the pressure-accessible orthorhombic phase of the KMgX family emerges as a stable multifunctional semiconductor with coupled photovoltaic and thermoelectric energy-conversion capabilities.

Entanglement spectra in gauge theories can encode both symmetry breaking and the organization of gauge sectors. In the two-flavor Schwinger model at vacuum angle $\theta=\pi$, we find that the joint Schmidt distribution $p_{Q_A,F_A}$, labeled by the subsystem gauge charge $Q_A$ and flavor imbalance $F_A$, reveals a cut-dependent gauge-sector hierarchy and a mass-induced flavor asymmetry: changing the staggered cut reorganizes the gauge-charge distribution $p_{Q_A}$, while mass imbalance breaks the $F_A\leftrightarrow-F_A$ symmetry of the conditional flavor distribution $p_{F_A|Q_A}$. Defining the combined weight $W_F^{(q)}=p_{q,+1}+p_{q,-1}$ and conditional polarization $\mathcal P_F^{(q)}=(p_{q,+1}-p_{q,-1})/W_F^{(q)}$, we find that changing the cut reverses the weight hierarchy, $W_F^{(-1)}>W_F^{(+1)}$ at unit-cell boundaries but $W_F^{(+1)}>W_F^{(-1)}$ at intra-cell cuts, while mass imbalance drives $\mathcal P_F^{(q)}$ away from zero with a $q$-dependent cut response. Symmetry resolution therefore separates gauge-sector ordering, sector weight, and flavor polarization that are mixed in the globally ordered entanglement spectrum.

A one-dimensional SQUID (superconducting quantum interference device) array/metamaterial is investigated numerically with respect to its localization properties due to nonlinearity in the absence of dissipation and periodic driving. The system possesses a conserved Hamiltonian function representing its energy, and supports localized modes of the discrete breather type even in the presence of a moderately high dc flux bias. The appearance of discrete breathers in that system has been largely overlooked in literature. We find a new type of discrete breather that is asynchronous, meaning that the frequency of oscillation of the SQUID at the central breather site is different than that of the SQUIDs at the other sites of the metamaterial. Nonlinear localization is investigated by initializing the system with a single-site excitation of given amplitude (initial amplitude) for a fixed value of the coupling coefficient, while parameters such as the dc flux bias, the single-site initial excitation amplitude, and/or the SQUID can vary independently. Using the energetic participation ratio as a measure of the degree of localization, the existence of asynchronous highly localized modes and transitions between delocalized (extended) and localized modes re identified.

When a crystal undergoes a second-order structural phase transition, such as in ferroelectrics, Peierls, and charge-density waves, the diverging fluctuations of the order parameter lead to the break- down of the standard phonon quasiparticle picture. Simulating these highly anharmonic regimes is notoriously challenging, as methods such as molecular dynamics suffer from a critical slowdown near the transition point, while the harmonic approximation fails dramatically at saddle points of the energy landscape stabilized by quantum or thermal ionic fluctuations. This work introduces a new approach, based on the variational free-energy principle, to predict critical long-range behavior and dynamical spectra in strongly anharmonic systems, even when quantum ionic fluctuations dominate. The proposed framework builds upon the stochastic self- consistent harmonic approximation but reduces its computational scaling with the number of atoms, N, from O(N^6) to O(N^2) and the memory requirement from O(N^4) to O(N). We benchmark the method on the prototypical lead-free metal-halide perovskite CsSnI3, a promising candidate for photovoltaic engineering, simulating its phase stability and Raman spectrum near the phase transition, where the breakdown of the quasiparticle picture becomes evident. We demonstrate the effectiveness of the method by computing the full free-energy Hessian and the critical temperature in a supercell with 1080 atoms. Such simulations would have required tens of thousands of years with the legacy approach; it is now feasible in a few hours on consumer hardware.

Quantum circuits are fundamental components of quantum computing, and state-vector-based quantum circuit simulation is a widely used technique for tracking qubit behavior throughout circuit evolution. However, simulating a circuit with $n$ qubits requires $2^{n+4}$ bytes of memory, making simulations of more than 40 qubits feasible only on supercomputers. To address this limitation, we propose the Qu-Trefoil, a system designed for large-scale quantum circuit simulations on an FPGA-based platform called Trefoil. Trefoil is a multi-FPGA system connected to eight storage subsystems, each equipped with 32 SATA disks. Qu-Trefoil integrates a suite of HLS-based universal quantum gates, including Clifford gates (Hadamard (H), Pauli-Z (Z), Phase (S), Controlled-NOT (CNOT)), the T gate, and unitary matrix computation, along with HDL-designed modules for system-wide integration. Our extensive evaluation demonstrates the system's robustness and flexibility, covering quantum gate performance, chunk size, disk extensibility, and efficiency across different SATA generations. We successfully simulated quantum circuits with over 43 qubits, which required more than 128 TB of memory, in approximately 3.72 to 13.06 hours on a single storage subsystem equipped with one FPGA. This achievement represents a significant milestone in the advancement of quantum computing simulations. Furthermore, thanks to its unique architecture, Qu-Trefoil is more accessible, flexible, and cost-efficient than other existing simulators for large-scale quantum circuit simulations, making it a viable option for researchers with limited access to supercomputers.

We demonstrate a reflective terahertz (THz) polarization conversion metasurface based on a double-ring aluminum resonator on a quartz substrate. Full-wave simulations are used to optimize the unit-cell geometry and investigate the polarization conversion mechanism through phase analysis, polarization ellipses, and surface-current distributions. The proposed metasurface exhibits a near-unity polarization conversion ratio (PCR) at resonance frequencies of 0.333 THz and 0.361 THz. Reflection-mode terahertz time-domain spectroscopy (THz-TDS) measurements show good agreement with the simulated results. The measured PCR exceeds 87% at both resonance frequencies, demonstrating efficient reflection-mode polarization conversion.

We present Pairton, an iterative framework for reconstructing short-lived particles in high-energy collision events. By formulating particle reconstruction as a masked prediction process over graph structures, Pairton learns conditional distributions consistent with a factorised decomposition of decay products and iteratively predicts edges in the adjacency matrix representing particle decay relationships. Leveraging a pairformer-based architecture with dynamically updated pairwise representations, our method incorporates global event consistency. We demonstrate state-of-the-art performance on fully hadronic $t\bar{t}$ decays. Pairton provides a general, flexible paradigm for particle reconstruction and can be readily extended to other topologies, bridging ideas from modern generative modelling and high-energy physics.

Uncertainty relations provide lower bounds for otherwise hidden quantities of a partially accessible Markov network like the mean entropy production rate and the total dynamical activity. The thermodynamic uncertainty relation (TUR) is arguably the most prominent one and involves the precision of a fluctuating net current. One of its major generalizations is the multidimensional TUR (MTUR), which yields a tighter bound by using covariances of a set of observed net currents. We generalize this latter bound to time-dependently driven processes with arbitrary initial state and arbitrary measurement duration. Furthermore, this bound can be used with a set of fluctuating counting observables each of which can be time-antisymmetric, time-symmetric or time-asymmetric, i.e., a net current, a traffic or a flow. We can even allow for coarse-grained observations in which each counting observable could consist of multiple indiscernable observed transitions of the underlying system. Thus, we generalize the MTUR, extensions of the TUR for time-dependent processes based on one current, and an estimator based on one flux or on one traffic in a unifying way. We illustrate this general uncertainty relation with simple examples.

For fixed Standard Model (SM) non-Abelian representations of 15 chiral fermions with arbitrary hypercharges, anomaly cancellation admits the usual assignment and a distinct nonstandard solution. In the latter, the exotic quark and lepton weak doublets and exotic lepton singlet have zero hypercharge, whereas the two exotic quark singlets carry opposite hypercharges $-q$ and $q$. The neutral exotic lepton singlets naturally provide heavy neutrinos. With two copies, the minimal model realizes the minimal type-I seesaw, yielding one massless active neutrino, and predicts $m_{\beta\beta}=1.2$–$4.1$ meV for normal ordering and $15.9$–$48.9$ meV for inverted ordering. In a direct SM realization, generating exotic-quark masses through the SM Higgs mechanism fixes their electric charges to $\pm 1/2$. A separate $SU(2)_{L'}$ realization of the nonstandard solution can allow exotic-quark masses ranging from several TeV to 10 TeV with order-one Yukawa couplings while all charged exotic particles carry charges $\pm q$. In both cases, the lightest exotic quark and lepton are generically stable, providing distinctive and potentially testable signatures while remaining compatible with current constraints.

The simultaneous production of a $W^\pm$ boson and a charmed hadron in proton-proton collisions offers a potential probe for constraining the strange quark parton distribution functions (PDFs). We study these processes at next-to-leading order in perturbative Quantum Chromodynamics within the general-mass variable-flavor-number scheme. By considering ratios of cross-section between oppositely charged mesons, uncertainties associated with unphysical scale choices and fragmentation functions are shown to effectively cancel out, leaving the uncertainty originating from the PDFs as the dominant one. By comparing our calculations with CT18A, MSHT20 and NNPDF4.0 PDFs with the recent ATLAS measurement at $\sqrt{s} = 13\,{\rm TeV}$ we find that CT18A, which imposes zero strangeness asymmetry, agrees best with the data, while MSHT20 and NNPDF4.0, both of which allow for a non-zero strangeness asymmetry, exhibit greater tension with the ATLAS data. The sensitivity to the strangeness asymmetry is further confirmed by the PDF reweighting methods. We also study the impact of possible intrinsic charm content of the proton finding no significant sensitivity. Finally, we explore the possibility of measuring these processes in proton-lead collisions. With the estimated detector efficiencies and projected luminositites at the high-luminosity LHC, these processes should be visible, yet with a rather limited constraining power for nuclear PDFs.

We consider the classical scattering of two gravitating compact objects in the presence of a massive scalar mediator, providing a simple model of exotic phenomena. Through dimensional analysis, we argue that such a process can only be classical in the presence of gravity, a consequence of which is that perturbing in the coupling of the scalar to a worldline is not separate from the post-Minkowskian expansion. When computing asymptotic observables, the massive mediator complicates the Fourier transforms to impact-parameter space at next-to-leading order. We reduce these to univariate parametric integrals - amenable to numerical integration - and produce analytic results for the linear impulse and the scattering angle to the second post-Minkowskian order. The scattering angle exhibits a maximum when the range of the scalar-mediated force is comparable to the impact parameter, a possible signature of a massive scalar mediator. In the opposite, large-mass regime we uncover a screening effect: integrating out the scalar sourced by each compact object reduces its gravitational mass by an amount linear in the scalar's mass. Both of these phenomena are next-to-leading-order effects.

We study coherent flows in Cosmicflows-4 (CF4) and its constituent catalogs. We fit monopole and dipole moments in nonoverlapping radial bins using a log-distance radial-velocity estimator. For each sample, the Planck 2018 $\Lambda$CDM prediction accounts for the actual positions, statistical weights, velocity covariance, and measurement covariance. Across six bins extending to $300,h^{-1},\mathrm{Mpc}$, the All Individual sample is broadly consistent with $\Lambda$CDM, with dipole and joint deviations of $2.29\sigma$ and $2.36\sigma$. The strongest localized feature occurs at $120$–$160,h^{-1},\mathrm{Mpc}$, where $|V_{\rm dip}|=628\pm82,\mathrm{km,s^{-1}}$ and the dipole deviation reaches $3.40\sigma$. The excess is concentrated toward negative supergalactic X and depends strongly on the survey window. TFR and 6dFGS favor larger dipoles, while SDSS and SN favor smaller ones. Removing 6dFGS reduces the upper-bin dipole deviation to $1.56\sigma$, while removing SN raises it to $3.77\sigma$. Nevertheless, the SN and 6dFGS dipoles remain mutually consistent when their covariance is included. SDSS is consistent with $\Lambda$CDM through $160,h^{-1},\mathrm{Mpc}$ but shows a separate rise at larger radii whose significance depends on the treatment of the monopole and shared distance-scale covariance. Overall, CF4 does not show uniformly anomalous motion across its full radial range. Instead, it contains localized and window-dependent features that should be tested with selection-matched mock catalogs and correlated calibration uncertainties.

We present SymQuPS, a SymPy-based algebra system in Python mainly aimed toward the phase space representation of quantum mechanics within the Cahill-Glauber formalism (including the Glauber-Sudarshan $P$, Wigner, and Husimi $Q$ representations). By extension, the package serves as an algebraic venue for canonical quantization. A key feature is the phase space representation of an arbitrary Lindblad master equation, which gives the phase space equation of motion of the quantum system. We describe the core functionalities of the package, consisting of $s$-ordered operators, the star products, and the phase space representation. Some examples of use are given to illustrate the application of the package, and the package's performance in typical use cases is discussed.

Fourier quasicrystals are aperiodic structures whose diffraction spectrum consists not of a dense set of Bragg peaks, as in ordinary quasicrystals, but of isolated ones scattered across a discrete, nonperiodic set. This sparse reciprocal-space structure should leave wave transport largely undisturbed except at a few selected wavevectors. We put this prediction to the test using surface water waves scattering off a two-dimensional Fourier quasicrystal. Full-field measurements reveal three distinct transport regimes as the incident wavevector increases: transparency, selective scattering, and strong scattering. By reconstructing the structure factor from the measured wavefields, we directly relate these regimes to the underlying reciprocal-space structure. Our results establish Fourier quasicrystals as a physical platform in which wave transport can be controlled through the organization of diffraction peaks in reciprocal space.

We study static, spherically symmetric traversable wormholes in trace-coupled gravity with action density f(R,T) = R + lambda T^2. The spacetime is built from C-infinity deformations of Schwarzschild that vanish identically outside a finite core, so the exterior is exactly Schwarzschild and no thin shell or junction surface is needed. Because f_R = 1, the metric equations remain second order and the matter problem reduces to a local algebraic reconstruction. For an anisotropic source, we derive unified inversion formulas for (rho, p_r, p_t) in terms of the effective source and the dimensionless trace variable chi = lambda T/(4 pi), and show that the admissible matter branch is the vacuum-connected real root of a cubic equation. The resulting parameter space contains regular positive-density and negative-density throat regimes, a critical boundary where the reconstruction degenerates, and a nonadmissible branch-failure sector. The geometry itself is branch-independent, but the reconstructed matter depends on the matter-Lagrangian prescription. On the admissible branch the radial NEC still fails at the throat, so the model localizes exoticity rather than removing it. The Ricci support and reconstructed matter remain confined to a finite interval, while the exterior tidal field is exactly Schwarzschild with ADM mass M. The results should be read as controlled existence and viability statements within the displayed ansatz families, not as a stability proof.

A tidal disruption event (TDE) occurs when a star passes sufficiently close to a black hole (BH) to be disrupted by its tidal forces. Although several hundred TDEs have been identified to date, only a small fraction launch relativistic jets. These jets are thought to be Poynting-flux-dominated outflows powered by the Blandford-Znajek (BZ) mechanism. However, the origin of the jet plasma required to account for the observed prompt emission remains poorly understood and constitutes a key unresolved problem in the formation of relativistic TDE jets. In this Letter, we propose magnetic reconnection near the BH as a physical mechanism for injecting plasma into the BZ jet during the super-Eddington accretion phase. Once sufficient magnetic flux accumulates near the BH, an equatorial current sheet forms, in which magnetic reconnection produces high-energy gamma rays. We demonstrate that photon-photon interactions generate a sufficient particle supply to account for the observed prompt emission. We further show that our plasma loading scenario allows the jet to remain magnetically dominated out to the prompt emission region and that magnetic dissipation can consistently reproduce the observed prompt emission properties. Furthermore, our scenario predicts MeV and GeV gamma-ray flares, providing a direct means of testing this scenario with future gamma-ray observatories.