Papers

We present new observations of a candidate O-type donor star in a high mass X-ray binary (HMXB) in M33. The candidate donor star is spatially coincident with a hard X-ray point source. The star's optical magnitude and colors are consistent with what is expected for a massive star. The four band optical/UV spectral energy distribution (SED) of the donor star is well fit by an O-giant model with an effective temperature of $\sim$43 kK, mass of 75$_{+9}^{-0.3}$ $M_{\odot}$, and surface gravity of log(g) of $\sim$3.8. We present four epochs of optical spectroscopy of the donor star taken with the Keck/DEIMOS spectrograph over the course of approximately one year. Features in the star's spectrum are consistent with an O-type star. The star's spectrum exhibits a strong H$\alpha$ emission line during all epochs of observation with a variable line profile. We measure the star's radial velocity for each epoch, which we use to fit for a systemic velocity. We find that the systemic velocity is offset from the local gas velocity from HI measurements, suggesting that the system has a peculiar velocity relative to the local gas. We observe a radial velocity shift in the He I absorption lines that is consistent with motion within a binary system.

Manufacturability is one of several constraints on developing solid-state quantum processors, along with qubit performance, control, connectivity, cryogenic operation, and fault tolerance. Chemical residues, structural disorder, and non-uniform interfaces introduced during fabrication can compromise qubit coherence. Two-dimensional (2D) materials, with their atomically thin crystals and van der Waals interfaces, offer routes to address some of these challenges. Their concurrent development as next-generation CMOS channel materials motivates an examination of whether relevant processes can be transferred to quantum chips. This Perspective evaluates the opportunities and limitations of 2D materials for CMOS-compatible quantum hardware.

As quantum software stacks scale up to support future fault-tolerant quantum hardware and algorithms, quantum compilation is becoming an increasingly important component of the stack. How do we ensure that our software stacks support dynamic algorithms, including patterns such as mid-circuit measurement feedforward and repeat-until-success, with hundreds of logical qubits and billions of quantum operations? To do so, we must re-think how we represent quantum programs beyond straight-line circuits, to representations that include classical structure and dynamism, and make this the default representation to consider when performing quantum compilation. In this work, we present important patterns and algorithms from fault-tolerant quantum applications which admit a structured representation that we argue is crucial to preserve, and set a challenge to the community to compile such representations without unrolling them into straight-line quantum circuits. We also explore the status quo of structured program support in quantum software, and ask ourselves the rhetorical question: how much more efficient can we make quantum compilation tooling when we take into account the additional information from classical structure?

We describe a fully explicit, four-dimensional, top-down de Sitter saddle, constructed via compactification of M-theory on the Riemann-flat manifold $T^7/\mathbb{Z}_8$. The solution has a vacuum energy of $5.02\cdot 10^{-10}\,M_\text{Pl}^4$, a hierarchy $m_{KK}/H\sim 10^{2}$, and is under control with respect to higher loop and higher-derivative corrections. The solution has an internal manifold with a diameter of a few Planck lengths, and it may be unstable due to loops of virtual 11d black hole microstates. While the solution is the first example of a top-down dS maximum from Riemann-flat manifolds in four dimensions and is realised explicitly enough to compute the vacuum energy precisely and the spectrum of light fields, it is far from being phenomenologically viable. The solution also suggests several promising directions in the search for higher quality dS saddles in the Riemann-flat Landscape, which we describe.

Working agricultural landscapes are often treated as background to wildfire disasters, even though they are managed fuel mosaics, productive assets, and parts of regional infrastructure systems. We examine vineyard wildfire resilience during the electrically initiated 2019 Kincade Fire in Sonoma County, California, using an open, event-anchored geospatial framework spanning 4,581 vineyard fields (8,813.2 ha), wildland vegetation, surveyed structures, roads, overhead smoke, and post-fire greenness. Sentinel-2, OpenET, gridMET, soils, terrain, NOAA smoke polygons, an ignition-date OpenStreetMap network, and three-dimensional data inventories were analyzed at native decision scales. Vineyard pixels showed substantially lower descriptive dNBR than wildland pixels inside the perimeter (means 0.130 and 0.337). This contrast did not identify a universal vineyard firebreak effect: a segment-clustered boundary model gave a small negative contrast at 100 m (tau = -0.0166) but changed across bandwidths, failed slope continuity, disappeared in a 100 m donut, and produced a wrong-signed placebo. A 250 m spatial GAM reversed the unconditional pattern: after conditioning on location, terrain, and water use, vineyard fraction was positively associated with dNBR, while residual Moran's I remained 0.519. Beyond spectral impact, all mapped vineyards intersected overhead smoke on at least one day (mean 7.78 potential smoke-days per field), 34.2% of road-network nodes were dead ends, and inside-perimeter vineyards showed a larger greenness deficit through 2021 (recovery ratios 0.815 inside and 0.854 outside). Lower immediate spectral impact therefore did not imply complete resilience. The study provides a reproducible urban-rural informatics template separating descriptive contrasts, conditional associations, exposure indicators, and recovery evidence for decisions in working landscapes.

Accretion disks in active galactic nuclei (AGN) are expected to host embedded stellar-mass black holes (BHs) whose gas capture rates can be highly super-Eddington. Without feedback, they would rapidly grow and deplete the disk, but at such high feeding rates, radiation is advected inward with the flow. We test whether the resulting accretion-powered jet and its shocked cocoon can (i) self-regulate the BH's growth rate and (ii) break out of the AGN disk. Using GIZMO, we perform three-dimensional simulations of a $10\,{\rm M}_\odot$ BH, embedded in dense AGN-disk gas, launching a particle-spawned jet whose mass flux scales with the accretion rate. We explore a range of jet velocities, ambient temperatures and densities, and three cooling regimes. We find that the jet-inflated cocoon stalls near the Bondi radius and maintains a modest aspect ratio and the self-regulated mass flux is determined by momentum balance at the Bondi radius. Cooling controls the mode of self-regulated accretion, from large-amplitude oscillation cycles at low metallicity to weak, quasi-steady modulation at solar metallicity. Scaling our results to outer disk conditions implies that mechanical feedback limits BH growth to within an order of magnitude of the Eddington rate – largely preventing the overgrowth problem. Over the same disk region, the cocoon remains confined within the disk. In the inner disk, accretion onto the embedded BHs is limited by tidal shear rather than the Bondi radius, and our simulations no longer apply. Whether runaway growth and cocoon breakout remains possible in these inner regions needs further study.

The Weak Gravity Conjecture admits a formulation in terms of long-range charged particle self-interactions being repulsive. We adopt a similar approach to the Axionic Weak Gravity Conjecture by considering long-range instanton interactions. At leading order, in the instanton separation, such interactions are mediated purely by massless scalar fields. Gravitational and gauge interactions are sub-leading. We formulate a repulsive interaction Axionic Weak Gravity Conjecture, which forms a bound on the scalar field dependence of the complex Euclidean instanton action. We show that in standard ultraviolet complete examples, this bound implies the usual formulation of the Axionic Weak Gravity Conjecture, while generally being stronger. Because this formulation is purely a statement about massless scalar fields, it implies that in the absence of massless scalars the usual bound on the axion decay constant could be modified.

Retarded thermal correlators, analytically continued to complex frequency, exhibit non-hydrodynamic poles and branch cuts that constrain hydrodynamics. We construct Gaussian Schwinger-Keldysh effective actions in which branch cuts arise from continua of relaxation poles and response functions are governed by Stieltjes transforms of relaxation-time densities. Dynamical KMS symmetry, positivity and stability constrain the spectra, while endpoint behaviour controls the local branch structure and near-edge pole scaling. The illustrative examples of uniform and power-law densities exhibit respectively beyond-all-orders pole-endpoint separation and a continuous interpolation between pole-pole and pole-branch-point termination. Finally, we show that an energy-dependent relaxation-time approximation in kinetic theory provides a microscopic realization of our branch cuts at zero momentum.

We provide an analytic realization of spontaneous parity and time-reversal breaking without thermal restoration in a local, unitary, ultraviolet-complete quantum field theory in $2+1$ dimensions with finitely many fields. The theory is defined by a relevant Yukawa deformation of a product of the critical biconical vector model and free massless Dirac fermions. This deformation induces a renormalization group flow whose infrared endpoint is a decoupled product of the critical vector model and the conformal Gross-Neveu-Yukawa model. At zero temperature, the vacuum preserves both symmetries, whereas upon heating, the theory undergoes an inverse thermal transition at a finite critical temperature. Above this temperature, a fermion mass, odd under parity and time reversal, is dynamically generated, and the broken phase persists to arbitrarily high temperatures.

We study the classical simulability of open quantum dynamics using random Clifford circuits doped with non-Clifford phase rotations and subject to local noise. We unravel the dynamics into stochastic quantum trajectories simulated with Clifford-augmented matrix product states, and introduce a simulation cost that quantifies the classical resources required. Optimizing this cost over stochastic unravelings, we identify noise-induced classical phases: extended parameter regions in which the dynamics can be fully disentangled by Clifford operations at arbitrary circuit depth. Their existence depends on both the noise model and the unraveling. Using a geometric representation of quantum channels, we analytically determine optimal unravelings for a broad class of noise models, with numerical simulations confirming the predicted phase boundaries. We further relate the optimal cost to the unraveling-independent nonstabilizerness of the channel and show that, together with trajectory-resolved entanglement and nonstabilizerness, it classifies distinct dynamical regimes. Finally, we show that these classical phases disappear in the averaged density-matrix description, where no unraveling freedom remains. Our results show that the emergence of classicality in noisy random circuits depends on the measurement scheme adopted to probe it, and paves the way to further studies on the classical simulability of driven-dissipative dynamics.

Small high-rate non-CSS stabilizer codes provide compact platforms for encoded quantum computation, but mixed-Pauli checks and limited native transversal logical gates complicate fault-tolerant dynamics. Block-level constructions offer an alternative by mapping an entire logical block to a physical circuit rather than compiling separately protected logical gates. We investigate this approach using the high-rate [[8,3,3]] non-CSS code and logical Trotter circuits as a testbed. We construct flagged syndrome-extraction circuits and establish a circuit-level memory pseudo-threshold near \(1.5\times10^{-3}\). We then apply our symplectic-transvection construction, which maps a logical Trotter circuit to a physical circuit with the same block pattern for any stabilizer code. Although this mapping preserves the intended unitary algebraically, encoded Trotter circuits exhibit asymmetry between logical-\(X\) and logical-\(Z\) failure channels. Single-fault analysis identifies the mechanism: a fault on the shared parity ancilla can propagate through the uncomputation network into an undetectable logical operator, reducing the effective circuit distance in the affected sector. We evaluate flag-conditioned recovery, biased-noise decoding, CliNR resource verification, flag postselection, and asymmetric gate-noise models. These methods suppress propagated faults but do not simultaneously suppress both logical sectors in the realistic configurations studied. A diagnostic protected limit removing the identified malignant first-order locations restores pseudo-threshold behavior in both sectors, approaching memory performance. These results demonstrate the potential of block-level logical constructions for non-CSS codes without rich native transversal gate sets and the joint protection of the parity network, analog rotation, and recovery required to preserve fault-tolerant distance.

Numerical simulations reveal how vortices stretch and transfer energy, but establishing smooth evolution requires bounds that remain valid beyond the simulated resolution. Here I develop a computer-assisted framework that establishes global regularity for continuous families of three-dimensional periodic Navier-Stokes flows. Its central construction combines finite reference trajectories with a common error bound that covers an interval of centre fields and infinitely many smooth perturbation modes. The method retains the complete nonlinear residual before spectral truncation and controls the evolution until viscous decay guarantees regularity for all subsequent times. Applications to cyclic-shear, Arnold-Beltrami-Childress and three-component Taylor-Green fields yield explicit perturbation radii and include initial conditions outside the direct Fourier-Wiener smallness criterion. A parameter-uniform extension covers a connected family of non-Beltrami Taylor-Green centres without repeating the proof for individual parameter values. An ensemble of 4,096 configurations, supplemented by 1,600 refinement trajectories and public turbulence data, connects the mathematical observables to spectral transfer and vortex geometry. Matched neural-operator experiments show that physics-informed training improves physical prediction, while also revealing that these gains do not necessarily improve the discovery of proof-limiting initial conditions. Together, these results provide a reusable method for establishing regularity across prescribed flow families and a quantitative setting for evaluating how learned predictions can assist rigorous computation.

We investigate a composite-inspired model in which a scalar dark matter candidate couples to third-generation quarks through a non-minimal set of coloured vector-like fermions, as motivated by partial compositeness. The simultaneous presence of several mediator states leads to a richer phenomenology than conventional single-mediator descriptions, and we confront the framework with the observed relic abundance, direct-detection and indirect-detection constraints, as well as data from the Large Hadron Collider. At colliders, we compare the sensitivity of dedicated new-physics searches with that of unfolded measurements of Standard Model processes, and we assess the impact of higher-order corrections on the different production mechanisms. We find that dedicated searches generally provide the strongest collider exclusions, while unfolded measurements offer complementary sensitivity. Direct detection becomes increasingly powerful as the interaction strength grows and can become the dominant constraint. This broader complementarity arises because collider data directly test the production and decay of the coloured mediators, whereas cosmological and astroparticle observables constrain the interactions governing dark-matter abundance, scattering and annihilation. Although present constraints significantly restrict the model, viable regions compatible with the observed dark-matter abundance remain.

The absence of new physics beyond neutrino masses between the weak scale and the Planck scale is referred to as the great desert. It is often seen as a nightmare scenario for particle physics. Here we argue, by contrast, that the great desert assumption in fact has dramatic implications: it predicts that the Standard Model has a semi-classical AdS$_4$ vacuum with CFT$_3$ dual and, under reasonable assumptions, must be accompanied by at least one extra dimension significantly larger than Planck length. We also present one plausible candidate CFT$_3$ to be “the" dual to the Standard Model.

Completeness is widely recognized in quantum information as an important property of a family of monotones, because it ensures that no information relevant to state conversion is lost. We show that completeness is also physically important in many-body systems: an incomplete measure of symmetry breaking can miss essential features of symmetry-restoration dynamics. We study the logarithmic characteristic function (LCF), also known as the string order parameter, whose full family is complete for exact i.i.d. pure-state conversion under symmetry-preserving operations for finite groups. We introduce a fidelity-based extension of the LCF to mixed states and identify two concrete advantages over entanglement asymmetry (EA). First, for a finite symmetry group $G$, EA is bounded by $\log |G|$ and can approach the same saturated value for different initial states in the thermodynamic limit, making their relaxation curves indistinguishable and preventing the identification of a discrete-symmetry Mpemba effect. By contrast, the LCF can remain extensive, with a coefficient that depends on the initial state and time, and therefore continues to distinguish their relaxation dynamics. Second, different LCF components can exhibit distinct relaxation and crossing behavior, including cases in which EA shows no crossing. We demonstrate these advantages in spin-chain quenches and a single-qubit system under depolarizing noise. We also develop a replica construction for the fidelity-based LCF in quantum field theory and derive analytical results for conformal field theory.

The ENTSO-E Transparency Platform is the single mandated publication point for European electricity market data, and three of its data items carry a production-type label. Commission Regulation (EU) No 543/2013 Article 16(1)(a) requires actual generation output per generation unit but does not mention production type; the label on that item is ENTSO-E's own addition through the schema, and Article 5(d) delegates the classification of production types to a Manual of Procedures. This data descriptor documents two preregistered datasets that measure what that classification does in practice, along four axes: simultaneous multi-fuel reporting, type change between capacity-register vintages, persistent misclassification without type change, and cross-product consistency between the per-unit and the aggregated series. Criteria were locked and checksummed before measurement, thresholds are derived from measured noise rather than chosen, and what did not survive is recorded: six claims are withdrawn, three of them from published versions of the datasets themselves. Across 2191 documents covering 199 generation units in three bidding zones where biomass co-firing is documented in a dated primary source, no unit carries two production types in the same document. One practical warning applies to every user of the hourly series: all of it carries curveType A03, a step curve in which a missing position means the previous value holds rather than that data are absent. A parser that sums only the points listed under-reports energy unevenly, by 22.6 percent for one Finnish unit in 2021.

We present a multi-epoch, primarily X-ray study of the narrow-line Seyfert 1 (NLSy1) galaxy Mrk~766 by combining archival XMM-Newton observations spanning nearly two decades together with a XRISM observation obtained during its Performance Verification Phase. We analyzed the absorption and emission features in the soft X-ray spectra from RGS and EPIC-pn data, revealing a stratified multi-phase potentially ionised absorber with a column density varying at a timescale of $\sim$1 day. The covering fraction shows positive correlation with the continuum flux, however with significant intrinsic scatter, between the epochs. Mrk~766 exhibits a multi-component Fe\,K$\alpha$ emission line as revealed by fits to the XRISM data. A quasi-phenomenological model comprising a torus and a broad diskline component distinguishes the two components and constrains the inner radius of the potential broad line emitting disk substructure between $R_{in}=40-60\,r_{\rm g}$. Analysis of multiple epochs of the Fe K$\alpha$ complex across XMM-Newton observations reveals that the broad component tracks the continuum flux closely and effectively reflects the trend with respect to the continuum. The narrow component is consistent with a distant emitter, potentially the torus. Quasi-simultaneous monitoring with Swift-XRT and UVOT further indicates UV emission lagging the X-rays by $5.9^{+4.1}_{-5.7}$ hours, consistent with disk reprocessing of coronal X-ray fluctuations, and corresponds to a light travel distance of up to $10^{3}\,r_{\rm g}$. Overall, our analysis maps the extent of the dynamically evolving absorber, the iron line emitter, and the accretion disk in this highly accreting NLSy1 system.

The super Schottky ideal defines the image of the superperiod map, which takes a family of genus $g$ supercurves to its Jacobian. We prove that if $g \geq 5$, then $d=g$ is the minimal number such that $I_{Sch,g}^d \subset I_{s-Sch,g}$, where $I_{Sch,g}$ is the Schottky ideal and $I_{s-Sch,g}$ is the super Schottky ideal.

We study the fate of quantum solids with a vanishing velocity of transverse phonons. Such “floppy” solids exhibit a cubic elastic nonlinearity that is relevant in spatial dimensions $d<4$ and drives the system to a strongly-coupled Lifshitz quantum critical point in $d=3$, that we analyze in an $\epsilon = 4-d$ expansion. The associated phase transition is generically first-order, preempting the system's full access to the strongly-coupled fixed point. Nevertheless, the critical data of this quantum critical point is accessible within a Ginzburg region in the vicinity of the transition. This cubic nonlinearity vanishes exactly in $d=2$, where the leading interactions are instead quartic and are marginal, leading to weak logarithmic singularities. We discuss possible realizations of this “crystal Lifshitz criticality” in quantum materials.

We study the Heisenberg XXX spin chain with twisted periodic boundary conditions with a defective twist matrix. Using quantum separation of variables, we show that the generalised eigenvectors of this system can be characterised in terms of a modified TQ equation that we have named "Jordanian TQ equation". We also show that the wavefunction in the separated basis is only separable for true eigenvectors, while the wavefunction for generalised eigenvectors of higher rank is given instead by a sum over weak compositions.

A decade ago, a landmark study on flow control via subsurface phonons transformed our understanding of fluid-structural interactions, compelling us to reimagine ways by which to suppress boundary layer instabilities. While subsequent investigations have steadily enriched this landscape, several questions remain largely unanswered. The notion of Tollmien-Schlicting (TS) wave stabilization relies on phase-engineered surface interactions, which destructively engage with the wave and impede its growth. Although the fundamental drivers of the phenomenon are established, its granular physics remain insufficiently resolved, particularly as it pertains to directional effects, competing energy production mechanisms, and the precise streamwise locations governing the process. Revisiting this initial vision, we confront these open questions, revealing fresh insights, and establishing broad foundational strokes to guide the next era of investigations. We begin by defining the amplitude and phase criteria of an elastic wall admittance driving perturbation energy changes relative to a rigid wall. The established framework isolates the roles of the work-rate, viscous energy, production, and dissipation in shaping the fluid's response and clarifies how each contributes to the collective outcome. Crucially, we demonstrate how streamwise translation of the interaction surface significantly alters these parameters, revealing critical thresholds at which the control result is fully reversed. Our model identifies specific pathways to sustained TS wave attenuation, and defines the limits of what can be accomplished passively. Finally, we conceptualize a two-dimensional phononic subsurface, whose tailored and disproportional response to the flow in the wall-normal and streamwise directions, brings about the elusive combination of local and downstream stabilization.

The discovery of high-$T_c$ superconductivity in multilayer nickelates has stimulated intense interest, yet the microscopic origins of their correlated states remain debated. Recently the observed isotope effect of the magnetic state in trilayer nickelates highlights the important role of lattice vibrations in shaping these systems. Here, we investigate the impact of electron-phonon coupling (EPC) on magnetism and superconductivity in trilayer nickelates using ab initio and functional renormalization group calculations. We identify out-of-plane oxygen breathing modes with pronounced EPC and construct symmetry-resolved, layer-dependent couplings. Their relative phases across the three layers generate distinct retarded interactions, producing mode-selective enhancement or suppression of spin-density-wave order and $s_\pm$-wave superconductivity. This selectivity arises from screening-mediated spin-phonon interplay across a hierarchy of energy scales: EPC modifies charge screening at higher energies, reshapes magnetic fluctuations at lower energies, and ultimately influences pairing. Selected modes yield negative isotope coefficients for the magnetic state, qualitatively consistent with experiments. Our results establish how interlayer phonons modify electronically driven order and provide a microscopic framework for understanding isotope effects in trilayer nickelates.

We investigate the utility of the locality-preserving Derby-Klassen (DK) fermion-to-qubit mapping [arXiv:2003.06939] for variational quantum simulation of two-dimensional $t$-$V$ and Fermi-Hubbard models. The DK mapping preserves the locality of fermionic interactions with an enlarged Hilbert space, thereby requiring additional constraints that define the physical sector. We incorporate these constraints directly into a Hamiltonian Variational Ansätz (HVA) through Clifford-gate state preparation and use the Variational Quantum Eigensolver (VQE) to show that the low-energy properties of the resulting qubit Hamiltonian are accurately reproduced. We further exploit particle-number conservation inherent in the ansätz to resolve distinct symmetry sectors and reliably access degenerate states. Consequently, we benchmark the DK-HVA against Jordan-Wigner-based variational circuits at nonzero chemical potential, where particle-hole symmetry and the associated half-filled sign-free condition are absent. Finally, we demonstrate the advantage of locality-preserving mappings in higher-dimensional fermionic systems, where the conventional Jordan-Wigner (JW) transformation generates increasingly long Pauli strings and corresponding circuit overheads. We further extend the framework to the spinful Fermi-Hubbard model and identify a tradeoff between fermionic-mode placement and the locality of hopping and on-site interaction terms. These results establish a practical framework combining locality-preserving fermion-to-qubit mappings, constraint-preserving Clifford state preparation, and symmetry-preserving variational circuits, that trades auxiliary-qubit and stabilizer-preparation overhead for reduced operator nonlocality, providing a practical route toward resource-efficient quantum simulation of higher-dimensional interacting fermionic systems.

We initiate a symmetry descent procedure for M-theory engineered quantum field theories. Starting from a higher form BF theory supplemented by a cubic bulk topological interaction, we construct a gauge-invariant bulk-boundary system whose edge modes acquire generalized Maxwell–Chern–Simons dynamics after the introduction of a metric-dependent boundary action. The nonlinear contribution to the boundary equation is induced entirely by the cubic bulk interaction. In the case of twelve dimensional bulk parent, the resulting boundary conditions reproduce the local flux equations of the eleven-dimensional supergravity $C$-field, including the gravitational $I_8$ correction. Thus, the electric–magnetic pairing and the nonlinear Maxwell–Chern–Simons dynamics descend from a single 12D topological model. Using Hypothesis H, we identify the bulk equations with the Sullivan model of $S^4$ and interpret their nonlinear gauge transformations as homotopies. We then propose a twisted 4-cohomotopy quantization of the bulk fields and a homotopy pullback description of the coupled bulk–boundary field space. The construction provides both a local dynamical mechanism for M-theory symmetry descent and a candidate global characterization of its fields.

We show that an $O(1)$ local defect is sufficient to generate approximate unitary $k$-designs from an otherwise integrable quantum many-body system. Using a two-Pauli-kick (2PK) protocol with temporal sampling, we demonstrate this mechanism in a fixed-magnetization sector of deterministic XXZ spin chains with a single integrability-breaking bulk defect. We derive an analytical selection rule for the Pauli kicks and show that symmetry-preserving strings with a specific domain-wall count, fixed by the couplings, govern design formation. An exhaustive search over all admissible Pauli strings identifies a broad family of kicks that produce designs in the chaotic regime, whereas no such kicks exist in the integrable limit, including for boundary defects. We further show that the design-forming mechanism remains effective for weak bulk defects as the system size increases.

Recent IceCube observations point to the ultra-high energy neutrino flux exhibiting a very soft spectral nature beyond tens of TeV, which is unexpected from the standard cosmic-ray neutrino connection. As a potential explanation for this behaviour, we investigate neutrino self-interactions in an extra-dimensional $ {U(1)}_{L_{\mu}-L_\tau} $ gauge theory, where symmetry breaking leads to a tower of Kaluza-Klein gauge bosons in compactified four dimensions. These multiple gauge bosons may enhance the attenuation of astrophysical neutrinos as they propagate in the C$\nu$B medium. Unlike single-mediator scenarios, for example, which arise from broken $ {U(1)}_{L_\mu - L_\tau} $ gauge symmetries in four dimensions, the presence of a Kaluza-Klein tower of mediators produces multiple closely spaced resonances whose interference gives rise to a rich energy-dependent behaviour of the scattering cross-section over a vast range of incident neutrino energies. Alongside $s$-channel resonances, off-resonant $t$- and $u$-channel contributions also become important. We explore the possibility that repeated resonant scattering between astrophysical neutrinos and those in the C$\nu$B, mediated by these new multiple gauge bosons may increasingly attenuate the former at higher energies, thereby addressing the possibility of softening its spectral nature within the consideration of a single power law.

We analyze observations of the Cassiopeia A core-collapse supernova remnant (CCSNR) and identify a pair of opposite rings, attributing their formation to unequal-energy explosion jets that also imparted the neutron star (NS) its kick velocity via the kick-BEAP (kick by early asymmetrical pair of jets) mechanism. We replicate the formation of these ring structures, which we identify as circum-jet rings, with three-dimensional hydrodynamical simulations of two opposite explosion jets in which the northern jet is much more powerful, forming the larger northern ring known as the Crown. The line connecting the centers of the two opposite rings passes through the previously-established point-symmetric center of Cassiopeia A. The momentum difference between the two jets also explains the observed southwards NS kick velocity of ~400 km/s. The kick-BEAP and point-symmetric morphology suggest powering and shaping by several pairs of jets during the explosion process, strengthening the jittering jets explosion mechanism for the Cassiopeia A CCSNR and core-collapse supernovae in general.

Recent experiments demonstrating superconducting-like characteristics in materials above their equilibrium transition temperatures following strong sub-picosecond optical excitation have stimulated theoretical interest in phase-disordered superconductors subject to a periodically modulated superfluid stiffness. Previous analyses of the single-layer optical conductivity have shown that such a drive can enhance the low-frequency $1/\omega$ response, even when the period-averaged stiffness remains unchanged. We extend these studies to bilayer systems, such as the YBa$_2$Cu$_3$O$_{6+x}$ (YBCO) cuprate, by considering drives with different symmetries. Specifically, we investigate a layer-symmetric drive, in which the two planes stiffen and soften simultaneously, and a layer-antisymmetric drive, in which one plane stiffens while the other softens. Both drives enhance correlations of the layer-averaged phase and generate comparable superconducting-like optical conductivities. Only the symmetric drive, however, strengthens relative-phase locking and the associated counterflow response to a magnetic field parallel to the planes. Thus, an enhanced $1/\omega$ optical conductivity does not by itself imply enhanced magnetic screening. In view of applications to driven YBCO, where superconducting-like in-plane optics and transient diamagnetism have both been reported, our result provides a symmetry diagnostic: within a phase-synchronization mechanism, the experimentally active low-frequency stiffness modulation must contain a substantial layer-symmetric component.

We derive the 4d $D$-term and $F$-term potential generated by a D7-brane stack in Calabi-Yau orientifold compactifications of type IIB string theory, taking into account the effect of worldvolume and ISD bulk fluxes and the non-Abelian nature of the brane fields. This potential is an important ingredient for moduli stabilization in IIB, e.g., in de Sitter scenarios using a T-brane uplift. While aspects of the $D$-term and $F$-term parts of the potential have been inferred before with various arguments, we provide here a unified first-principles derivation of the full potential by dimensionally reducing the non-Abelian DBI action of the D7-branes. Our result generalizes previous expressions and agrees with them where applicable, thus confirming the mutual consistency of the various approaches. Moreover, we provide a thorough discussion of corrections from integrating out KK modes and argue that demanding control over such corrections implies bounds on the Calabi-Yau volume and the brane fields. Aside from these various results for the 4d effective action, our calculation also shows how bulk fluxes correct the potential and the BPS equations in the 8d worldvolume theory that governs the microscopic dynamics of non-Abelian branes.

We present a three-dimensional visco-magnetoacoustic framework for analog gravity in magnetohydrodynamic (MHD) flows. While standard fluid dissipation typically breaks the Lorentzian signature of acoustic metrics, we demonstrate that evaluating wave perturbations in the eikonal limit alongside the Shakura-Sunyaev $\alpha$-viscosity prescription preserves a well-defined effective spacetime geometry for the fast magnetoacoustic mode. The slow-magnetoacoustic mode and Alfvén mode do not admit a non-degenerate metric. To investigate analog horizon thermodynamics, we utilize astrophysical accretion disks as background media, specifically modeling numerical magnetized advective accretion flows around rotating black holes and analytical advection-dominated inflow-outflow solutions (ADIOS). Standard self-similar ADIOS models strictly enforce a constant Mach number, precluding horizon formation. We therefore introduce a magnetic field perturbation that breaks self-similarity, generates a dynamic Mach number, and enables the formation of a visco-magnetoacoustic horizon. By evaluating the spontaneous phonon emission at these horizons, we reveal that the analog Hawking temperature is highly sensitive to the magnetic field topology; the spatial orientation of the background magnetic gradients dictates whether the Hawking radiation is amplified or suppressed. Furthermore, we find that increasing the viscosity parameter leads to a monotonic increase in the analog Hawking temperature.