We investigate the in-medium spectral functions and effective masses of heavy quarkonia charmonium ($J/\mathrm{\Psi }$) and bottomonium [$\mathrm{\Upsilon }(1S)$] in a quark-gluon plasma (QGP) possessing both global rotation and spatial anisotropy. Using a gauge/gravity holographic model incorporating finite temperature, chemical potential, and warp factor, we compute the spectral signatures nonperturbatively. Our results show that both rotation and anisotropy enhance quarkonium dissociation, manifesting as peak suppression and width broadening in the spectral functions. Crucially, their effects are directional: anisotropy primarily dissociates longitudinally polarized states, while rotation more strongly disrupts transversely polarized ones. A competitive interplay exists: for small anisotropy, rotational effects dominate at high angular velocity, whereas for large anisotropy, anisotropy governs the dissociation regardless of rotation strength. Furthermore, rotation induces a nonmonotonic temperature dependence in the transverse effective mass of $J/\mathrm{\Psi }$, while strong anisotropy causes similar nonmonotonicity in the longitudinal effective mass of $J/\mathrm{\Psi }$. These findings reveal how the distinct symmetry breaking patterns induced by QGP rotation and anisotropy reshape the heavy quarkonium spectrum, providing new insights into polarization-dependent suppression in noncentral heavy-ion collisions.

The rare radiative decay ${\mathrm{\Xi }}_{bb}^{*}\to {\mathrm{\Xi }}_b\gamma$ is investigated within the light cone QCD sum rules approach. This decay proceeds through the flavor changing neutral current $b\to s$ transition in the Standard Model. The hadronic matrix element of the considered decay is parameterized in terms of four tensor form factors $T_1^V(q^2)$, $T_2^V(q^2)$, $T_1^A(q^2)$, and $T_2^A(q^2)$. The sum rules for these form factors describing the ${\mathrm{\Xi }}_{bb}^{*}\to {\mathrm{\Xi }}_b\gamma$ decay are derived at $q^2=0$ point using the ${\mathrm{\Xi }}_b$ distribution amplitudes. The results of the form factors are employed to calculate the corresponding decay width. Our finding indicates that this weak radiative decay could be within reach of future high statistics studies of doubly heavy baryons at LHCb and upcoming facilities.

Beyond the Standard Model scenarios introduce additional scalar and fermion multiplets, which influence neutrino mass generation mechanisms and yield distinctive collider signatures. This work focuses on a particular scenario involving a fermion quintuplet and a scalar quadruplet. The study examines the production and decay of the scalar quadruplet components at the Large Hadron Collider (LHC), emphasizing how their decay patterns, fermiophobic versus fermiophilic, depend on mass differences and Yukawa couplings with the fermion multiplets. This study provides an overview of possible signals at the LHC, along with a detailed collider analysis focused on final states containing at least four leptons and two jets, in which the masses of the scalars and fermions are reconstructed successfully. Standard Model backgrounds are also incorporated in the study, with multivariate techniques leveraged via boosted decision trees. Results indicate discovery potential for scalar masses around 600–700 GeV and exclusion sensitivity extending beyond 1 TeV, highlighting the promising experimental signatures of the model and its role in probing new physics at colliders.

We propose a forward-mode automatic differentiation (AD) framework for tensor renormalization group methods. In this approach, evaluating the derivatives of the partition function up to the order of $k$ increases the matrix-multiplication cost by a factor of $(k+1)(k+2)/2$ compared to computing the free energy alone, and the memory footprint is only $k+1$ times that of the original calculation. In the limit where the derivatives of the singular value decomposition are neglected, we establish a theoretical correspondence between our forward-mode AD and conventional impurity methods. Numerically, we find that the proposed AD algorithm can calculate internal energy and specific heat significantly higher accuracy than the impurity method at comparable computational cost. We also provide a practical procedure to extract critical exponents from derivatives of the renormalized tensor in tensor renormalization group calculations in both two and three dimensions. In addition, we discuss how to efficiently differentiate an arbitrary tensor network.

We provide some critical remarks on the recently proposed two-component parametrization of nuclear parton distribution functions, which was motivated by the apparent correlation between the nuclear modifications of structure functions and nucleon-nucleon short-range-correlation phenomena. This parametrization, we show, is invariant under a rescaling transformation of the involved abundance coefficients, which means that the global normalization of these coefficients cannot be meaningfully determined in a fit, and only their ratios should be studied for finding evidence of short-range-correlation–type behavior at parton level. As we show, however, the current constraints for the nuclear-mass dependence of these coefficients allow also for interpretations different from short-range correlations. Nevertheless, this two-component parametrization exhibits a similar scaling relation for deep inelastic scattering structure functions as demonstrated in earlier works, and, as we demonstrate, yields testable predictions for structure-function and hard-process cross-section ratios. We also note on the nontrivial isospin dependence of the short-range-correlation motivated parametrization, which under the proton-neutron pair dominance assumption can lead to charge-symmetry-violation resembling terms.

We present a next-to-next-to-leading-order (NNLO) calculation within the nonrelativistic QCD framework for the process $e^{+}{e}^{-}\to Z^{*}\to J/\psi +J/\psi$. We find that the NNLO contribution is two to three times larger than the next-to-leading-order contribution, which itself is already three to five times larger than the leading-order result. In the high-energy limit, we provide analytic expressions for the leading-power coefficients in the asymptotic expansion of the two-loop amplitudes. Our results are directly applicable to the bottomonium process $Z\to \mathrm{\Upsilon }+\mathrm{\Upsilon }$. Using the obtained hadronic amplitudes, we predict the decay width of the $Z$ boson into these rare dicharmonium and dibottomonium final states.

Within the collinear factorization framework based on generalized parton distributions, we calculate the spin density matrix of exclusively produced quark and antiquark pairs $u\overline{u}$, $d\overline{d}$, $s\overline{s}$, $c\overline{c}$, $b\overline{b}$ in electron-proton scattering. The presence of both real and imaginary parts in the scattering amplitudes leads to a rich pattern of entanglement between the quark and the antiquark. We map out kinematical regions where the pairs exhibit entanglement, Bell nonlocality, and nonstabilizerness. We also predict that massive quarks and antiquarks are transversely polarized, similar to the well-known transverse hyperon polarization in unpolarized collisions. In strangeness, charm, and bottom productions, the polarization can reach 50%–80% in certain kinematic regions in the low-energy runs of the Electron-Ion Collider.

We study the dissociative associated production of a $J/\psi$ meson and a dimuon via double parton scattering (DPS) in nucleus-proton ultraperipheral collisions. This new channel, characterized by a rapidity gap, is sensitive to the photon and gluon distributions of the proton. We derive a DPS pocket formula for this process, together with a corresponding expression for the effective cross section. Furthermore, we demonstrate the kinematic dependence of the effective cross section and present predictions for the differential DPS cross section at LHC and FCC energies.

We explore how recent advances in the manipulation of single-ion wave packets open new avenues for detecting weak magnetic fields sourced by ultralight dark matter. A trapped ion in a “Schrödinger’s cat” state can be prepared with its spin and motional degrees of freedom entangled and be used as a matter-wave interferometer that is sensitive to the Aharonov-Bohm-like phase shift accumulated by the ion over its trajectory. The result of the spin-motion entanglement is a parametrically enhanced sensitivity to weak magnetic fields as compared with an unentangled ion in a trap. Taking into account the relevant boundary conditions, we demonstrate that a single trapped ion can probe unexplored regions of kinetically mixed dark-photon dark matter parameter space in the ${10}^{-15}\mathrm{eV}\lesssim m_{A^{\prime }}\lesssim {10}^{-14}\mathrm{eV}$ mass window. We also show how such a table-top quantum device will also serve as a complementary probe of axionlike particle dark matter in the same mass window.

A time- and flavor-integrated amplitude analysis of $B^0$ and $B_s^0$ decays to the $(K^{+}{\pi }^{-})(K^{-}{\pi }^{+})$ final state in the $K^{*}(892{)}^0{\overline{K}}^{*}(892{)}^0$ region is presented, using $pp$ collision data recorded with the LHCb detector in 2011–2018, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. The branching fractions of the $B^0$ and $B_s^0$ decays are measured relative to the $B^0\to D^{-}{\pi }^{+}$ and $B_s^0\to D_s^{-}{\pi }^{+}$ modes, respectively. The corresponding longitudinal polarization fractions are found to be $f_L^d=0.600\pm 0.022\pm 0.017$ and $f_L^s=0.159\pm 0.010\pm 0.007$, where the uncertainties are statistical and systematic, respectively. The theory-motivated ratio of the squared $B_s^0$ to $B^0$ longitudinally polarized decay amplitudes is found to be $L_{K^{*0}{\overline{K}}^{*0}}=4.92\pm 0.55\pm 0.48\pm 0.02\pm 0.10$, where the uncertainties are statistical, systematic, due to uncertainty of external mass and lifetime measurements, and due to knowledge of the fragmentation fraction ratio, respectively. This confirms the previously reported tension between experimental determinations and theoretical predictions of longitudinal polarization in $B\to VV$ decays at the level of 4.4 standard deviations.

We present the first exact, nonsingular black hole solution in general relativity sourced by a Dirac-Born-Infeld (DBI) scalar field. Crucially, the solution is exclusively supported by the phantom branch of the DBI action, dynamically replacing the central singularity with a regular core. The solution is asymptotically flat, possesses nontrivial scalar hair, and replaces the central singularity with a regular two-sphere. The mechanism for singularity resolution is a dynamical kinetic stiffness, which also explains the evasion of classical no-hair theorems. We show these black holes evaporate to a nonsingular relic with mass of the order of a gram. This provides a robust mechanism to evade standard evaporation constraints, opening a vast, previously forbidden mass window for light primordial black holes to constitute dark matter. The model is testable via distinctive gravitational-wave signatures from its scalar hair.

We introduce the notion of higher Berry connection and curvature in the space of conformal boundary conditions in $(1+1)\mathrm{d}$ conformal field theories, related to each other by exactly marginal boundary deformations, forming a “boundary conformal manifold.” Our definition builds upon previous works on tensor networks, such as matrix product states, where the triple inner product or multiwavefunction overlap plays a key geometric role. On the one hand, our boundary conformal field theory formulation of higher Berry phase provides a new analytic tool to study families of invertible phases in condensed matter systems. On the other hand, it uncovers a new geometric structure on the moduli space of conformal boundary conditions, beyond the usual Riemannian structure defined through the Zamolodchikov metric. When the boundary conformal manifold has an interpretation as the position moduli space of a D-brane, our higher Berry connection coincides with the Neveu-Schwarz-Neveu-Schwarz (NS-NS) B-field in string theory. The general definition does not require such an interpretation and is formulated purely field theoretically, in terms of correlation functions of boundary-condition-changing operators. We also explore a connection between higher Berry connections and functional Berry connections in the loop spaces of boundary conformal manifolds.

In this work, we study the constraints on the characteristic parameters $\{\zeta ,b\}$ of the Deser-Woodard nonlocal gravity model in a static and spherically symmetric background, using four classes of high-precision solar-system experiments: stellar light deflection, Shapiro time delay, perihelion advance, and geodetic precession. From geodesic equations, we derive observable geometric quantities that can be directly compared with VLBI/VLBA astrometry, the Cassini time-delay measurement, MESSENGER data, and the GP-B/LLR results. Our results show that a larger value of $b$ suppresses the nonlocal effect more rapidly with a radius, thereby weakening the overall constraints on $\zeta$. The perihelion advance exhibits the strongest sensitivity to $\zeta$ around $b\simeq 1.06$, providing the tightest single experiment bound, whereas away from this region the combined constraint becomes dominated by the Shapiro time delay. Incorporating all four experiments yields a well-defined and sharply bounded allowed region for the parameter space $\{\zeta ,b\}$.

A black hole binary approaching merger undergoes changes in its inspiral rate as energy and angular momentum are lost from the orbits into the horizons. This effect strengthens as the black holes come closer. We use numerical relativity data to model this so-called tidal heating in the strong-gravity regime. We also present a frequency-domain approximant for nonspinning black hole binaries that accounts for tidal heating effects up to the merger frequency. The approximant includes horizon parameters that characterize the nature of the compact objects. This model serves two main purposes: (1) leveraging the stronger effects of tidal heating near merger, it allows for more robust tests for the presence of black holes compared to the tests with inspiral-only analytical waveforms, and (2) by applying this model to a binary black hole baseline waveform that incorporates tidal heating, one can construct more accurate point-particle waveforms free from the finite-size effects of the component objects. We discuss its ramifications in modeling binary neutron star systems.

Geodesic flows emanating from an arbitrary point $𝒫$ in a manifold $ℳ$ carry important information about the geometric properties of $ℳ$. These flows are characterized by Synge’s world function and van Vleck determinant—important biscalars that also characterize quantum description of physical systems in $ℳ$. If $𝒫$ is a regular point, these biscalars have well-known expansions around their flat space expressions, quantifying local flatness and the equivalence principle. We show that, if $𝒫$ is a singular point, the scaling behavior of these biscalars changes drastically, capturing the nontrivial structure of geodesic flows near singularities. This yields remarkable insights into classical structure of spacetime singularities and provides useful tool to study their quantum structure.

The final equilibrium stage of stellar evolution can result in either a black hole or a compact object, such as a white dwarf or neutron star. In general relativity, both stationary black holes and stationary stellar configurations are known to be axisymmetric, and black hole rigidity has been extended to several higher curvature modifications of gravity. In contrast, no comparable result had previously been established for stationary stars beyond general relativity. In this work, we extend the stellar axisymmetry theorem to a broad class of diffeomorphism-invariant metric theories. Assuming asymptotic flatness and standard smoothness requirements, we show that the Killing symmetry implied by thermodynamic equilibrium inside the star uniquely extends to the exterior region, thereby enforcing rotational invariance. This demonstrates that axisymmetry of stationary stellar configurations is not a feature peculiar to Einstein gravity but a universal property of generally covariant gravitational theories, persisting even in the presence of higher curvature corrections.

The Hubble parameters measured by the Dark Energy Spectroscopic Instrument (DESI) DR2 baryon acoustic oscillation (BAO) observations show a significant discrepancy from the prediction of the standard cosmological model. This discrepancy, together with the long-discussed Hubble tension, may originate from large-scale inhomogeneities in the matter distribution. This interpretation is motivated by infrared galaxy surveys, which suggest that our galaxy resides within the $\sim 300\mathrm{Mpc}$ underdense region known as the Keenan-Barger-Cowie void. In this study, we apply a linear-order relation—relating the horizon-scale Hubble parameter inferred from cosmic microwave background observations and the local-scale Hubble parameter—to the $\mathrm{Pantheon}+\text{Type}$ Ia supernovae and the DESI DR2 BAO data. We show that a simple inhomogeneous cosmological model consisting of eight top-hat shells can consistently explain the Hubble parameters inferred from both observations. Based on the matter-density distribution, we also briefly discuss its possible impact on cosmological observables, including the magnitude-redshift relation, the kinematic Sunyaev-Zel’dovich effect, and the integrated Sachs-Wolfe effect.

We present a numerical investigation of nonlinear cluster lens reconstruction using weak lensing mass mapping. Recent advances in imaging and shear estimation have pushed reliable reduced shear measurements closer to cluster cores, making mass reconstruction accessible in the nonlinear regime. However, the Kaiser-Squires based algorithm becomes unstable in cluster cores, where convergence $\kappa$ significantly deviates from zero and the linear approximation breaks down. To address this limitation, we develop a reconstruction framework with two key modifications: applying smooth masks in these regions and using a model-derived analytical solution as the initial guess, rather than assuming $\kappa =0$. We validate our framework using simulated cluster lensing data with known mass distributions, incorporating realistic masks that arise from limitations in reduced shear measurements. We show that in the absence of shape noise, our framework yields high-fidelity mass reconstruction in regions with large reduced shear, with the best-performing method achieving residuals below $0.02\sigma$ in the unmasked regions. We further discover that iterative reconstruction methods can diverge beyond an optimal iteration count. Our modifications effectively suppress this instability, pushing mass reconstruction to higher accuracy and stability in the nonlinear regime.

Upcoming galaxy surveys will bring a wealth of information about the clustering of matter at small scales, but modeling small-scale structure beyond $\mathrm{\Lambda }$ cold dark matter ($\mathrm{\Lambda }\mathrm{CDM}$) remains computationally challenging. While accurate $N$-body emulators exist to model the matter power spectrum for $\mathrm{\Lambda }\mathrm{CDM}$ and some limited extensions, it is unfeasible to generate $N$-body simulation suites for all candidate models. Motivated by recent hints of an evolving dark energy equation of state from galaxy surveys, we assess the viability of employing the comoving Lagrangian acceleration (COLA) method to generate simulation suites assuming the $w_0{w}_a$ dynamical dark energy model. Following up on our previous work, we combine COLA simulations with an existing high-precision $\mathrm{\Lambda }\mathrm{CDM}$ emulator to extend its predictions into new regions of parameter space. We assess the precision of our emulator at the level of the matter power spectrum, finding that our emulator can reproduce the nonlinear boosts from euclidemulator2 at less than 2% error. Moreover, we perform an analysis of a simulated cosmic shear survey akin to future data from the first year of observations from the Legacy Survey of Space and Time (LSST), assessing the differences in parameter constraints between our COLA-based emulator and the benchmark emulator. We find our emulator to be in excellent agreement with the benchmark, achieving less than $0.3\sigma$ shifts in cosmological parameter constraints across multiple fiducial cosmologies. We further compare our emulator’s performance to a commonly used approach: assuming the $\mathrm{\Lambda }\mathrm{CDM}$ boost can be employed for extended parameter spaces without modification. We find that our emulator yields a significantly smaller $\mathrm{\Delta }{\chi }^2$ distribution, parameter constraint biases, and a more accurate figure of merit compared to this second approach. These results demonstrate that COLA emulators provide a computationally efficient and physically motivated path forward for modeling nonlinear structure in extended cosmologies, offering a practical alternative to full $N$-body suites in the era of precision cosmology.

We perform a multiprobe analysis combining cosmic microwave background (CMB) data from Planck and the Atacama Cosmology Telescope (ACT), ACT CMB lensing, and large-scale structure (LSS) measurements from the Dark Energy Spectroscopic Instrument (DESI), including DESI Legacy Imaging Survey (LS) galaxies and baryon acoustic oscillations (BAOs). We present the first $5\times 2\mathrm{pt}$ analysis of ACT DR6 lensing, DESI LS, and Planck Integrated Sachs-Wolfe (ISW). Within $\mathrm{\Lambda }\mathrm{CDM}$, this yields $S_8={\sigma }_8({\mathrm{\Omega }}_m/0.3{)}^{0.5}=0.819\pm 0.016$, in good agreement with primary CMB inferences and provides a sound-horizon-free Hubble constant constraint of $H_0=70.0\pm 4.4\mathrm{km}{\mathrm{s}}^{-1}{\mathrm{Mpc}}^{-1}$. Then, combining with CMB primary and BAO, we reconfirm a CMB–BAO discrepancy in the ${\mathrm{\Omega }}_m–\frac{D_v}{r_d}$ plane, which is heightened when combining BAO with the $5\times 2\mathrm{pt}$ data vector. We explore two dark-energy extensions that may reconcile this: an early-time modification, early dark energy (EDE), and late-time dynamical dark energy (DDE) parametrized by $w_0{w}_a$. For CMB $\mathrm{primary}+\mathrm{BAO}+5\times 2\mathrm{pt}$, we find a $3.3\sigma$ preference for DDE over $\mathrm{\Lambda }\mathrm{CDM}$, while EDE is modestly favored at $2.3\sigma$. The models address different shortcomings of $\mathrm{\Lambda }\mathrm{CDM}$: DDE relaxes the neutrino mass bound ($M_{\nu }<0.17\mathrm{eV}$ vs $<0.050\mathrm{eV}$ under $\mathrm{\Lambda }\mathrm{CDM}$), making it compatible with neutrino oscillation measurements, while EDE raises the Hubble constant to $H_0=70.5\pm 1.2\mathrm{km}{\mathrm{s}}^{-1}{\mathrm{Mpc}}^{-1}$, easing the discrepancy with SH0ES. However, neither model resolves both issues simultaneously. Our analysis indicates that both DDE and EDE remain viable extensions of $\mathrm{\Lambda }\mathrm{CDM}$ within current uncertainties and demonstrates the capacity of combined probes to place increasingly stringent constraints on cosmological parameters.