We study a doubly bottomed tetraquark state $(bb\overline{u}\overline{d})$ with quantum number $I(J^P)=0(1^{+})$, denoted by $T_{bb}$, in lattice QCD with the nonrelativistic QCD (NRQCD) quark action for $b$ quarks. Employing ($2+1$)-flavor gauge configurations at $a\approx 0.09\mathrm{fm}$ on ${32}^3\times 64$ lattices, we have extracted the coupled-channel potential between $\overline{B}{\overline{B}}^{*}$ and ${\overline{B}}^{*}{\overline{B}}^{*}$ in the HAL QCD method, which predicts an existence of a bound $T_{bb}$ below the $\overline{B}{\overline{B}}^{*}$ threshold. By extrapolating results at $m_{\pi }\approx 410$, 570, 700 MeV to the physical pion mass $m_{\pi }\approx 140\mathrm{MeV}$, we obtain a binding energy with its statistical error as $E_{\text{binding}}^{(\mathrm{single})}=155(17)\mathrm{MeV}$ and $E_{\text{binding}}^{(\mathrm{coupled})}=83(10)\mathrm{MeV}$, where “coupled” means that effects due to virtual ${\overline{B}}^{*}{\overline{B}}^{*}$ states are included through the coupled channel potential, while only a potential for a single $\overline{B}{\overline{B}}^{*}$ channel is used in the analysis for “single.” A comparison shows that the effect from virtual ${\overline{B}}^{*}{\overline{B}}^{*}$ states is quite sizable to the binding energy of $T_{bb}$. We estimate systematic errors to be $\pm 20\mathrm{MeV}$ at most, which are mainly caused by the NRQCD approximation for $b$ quarks.

In this work, we adopt the one-boson-exchange model to study the $Y_c{K}^{(*)}(Y_c={\mathrm{\Lambda }}_c,{\mathrm{\Sigma }}_c)$ interactions. After considering both of the $S-D$ wave mixing effects and the coupled channel effects, we can predict several possible open-charm molecular pentaquarks, i.e., the single ${\mathrm{\Sigma }}_c{K}^{*}$ molecular states with $I(J^P)=1/2(1/2^{-})$, $1/2(3/2^{-})$, and $3/2(1/2^{-})$, the coupled ${\mathrm{\Lambda }}_c{K}^{*}/{\mathrm{\Sigma }}_c{K}^{*}$ molecular states with $1/2(1/2^{-})$ and $1/2(3/2^{-})$, and the coupled ${\mathrm{\Sigma }}_{c}K/{\mathrm{\Lambda }}_c{K}^{*}/{\mathrm{\Sigma }}_c{K}^{*}$ molecular state with $1/2(1/2^{-})$. Meanwhile, we extend our study to the $Y_c{\overline{K}}^{(*)}$ interactions, and our results suggest that the ${\mathrm{\Sigma }}_c\overline{K}$ system with $I(J^P)=1/2(1/2^{-})$, the ${\mathrm{\Sigma }}_c{\overline{K}}^{*}$ systems with $1/2(1/2^{-})$, $1/2(3/2^{-})$, and $3/2(3/2^{-})$, the coupled ${\mathrm{\Lambda }}_c{\overline{K}}^{*}/{\mathrm{\Sigma }}_c{\overline{K}}^{*}$ system with $1/2(1/2^{-})$, and the ${\mathrm{\Sigma }}_c\overline{K}/{\mathrm{\Lambda }}_c{\overline{K}}^{*}/{\mathrm{\Sigma }}_c{\overline{K}}^{*}$ system with $1/2(1/2^{-})$ can be the prime molecular candidates.

We study the axion of quantum chromodynamics in hot and/or dense quark matter, within a Nambu-Jona-Lasinio-like model that includes the coupling of the axion to quarks. First, we compute the effects of the chiral crossover on the axion mass and self-coupling at finite temperature and baryon density, implementing local electrical neutrality and $\beta$-equilibrium. We find that the low energy properties of axion are very sensitive to the phase transition of quantum chromodynamics, in particular, when the bulk quark matter is close to criticality. Then, for the first time in the literature we compute the axion potential at finite quark chemical potential and study the axion domain walls in bulk quark matter. We find that the energy barrier between two adjacent vacuum states decrease in the chirally restored phase: this results in a lower surface tension of the walls. Finally, we comment on the possibility of production of walls in dense quark matter.

The evolution kernels that govern the scale dependence of the generalized parton distributions are invariant under transformations of the $\mathrm{SL}(2,\mathrm{R})$ collinear subgroup of the conformal group. Beyond one loop the symmetry generators, due to quantum effects, differ from the canonical ones. We construct the transformation that brings the full symmetry generators back to their canonical form and show that the eigenvalues (anomalous dimensions) of the new, canonically invariant, evolution kernel coincide with the so-called parity respecting anomalous dimensions. We develop an efficient method that allows one to restore an invariant kernel from the corresponding anomalous dimensions. As an example, the explicit expressions for next-to-next-to-leading order invariant kernels for the twist-two flavor-nonsinglet operators in QCD and for the planar part of the universal anomalous dimension in $\mathcal{N}=4$ supersymmetric Yang-Mills are presented.

A large amount of data on hadronic two-body weak decays of antitriplet charmed baryons $T_{c\overline{3}}$ to an octet baryon $T_8$ and an octet or singlet pseudoscalar meson $P$, $T_{c\overline{3}}\to T_{8}P$, have been measured. The SU(3) flavor symmetry has been applied to study these decays to obtain insights about weak interactions for charm physics. However not all such decays needed to determine the SU(3) irreducible amplitudes have been measured forbidding a complete global analysis. Previously, it was shown that data from measured decays can be used to do a global fit to determine all except one parity-violating and one parity-conserving amplitudes of the relevant SU(3) irreducible amplitudes causing 8 hadronic two body weak decay channels involving ${\mathrm{\Xi }}_c^0$ to $\eta$ or ${\eta }^{\prime }$ transitions undetermined. It is important to obtain information about these decays in order to guide experimental searches. In this work using newly measured decay modes by BESIII and Belle in 2022, we carry out a global analysis and parametrize the unknown amplitudes to provide the ranges for the branching ratios of the eight undetermined decays. Our results indicate that the SU(3) flavor symmetry can explain the measured data exceptionally well, with a remarkable minimal ${\chi }^2/\mathrm{d}.\mathrm{o}.\mathrm{f}.$ of 1.21 and predict 80 observables in 45 decays for future experimental data to test. We then vary the unknown SU(3) amplitudes to obtain the allowed range of branching ratios for the eight undetermined decays. We find that some of them are within reach of near future experimental capabilities. We urge our experimental colleagues to carry out related searches.

The popular waveform templates of extreme-mass-ratio inspirals usually omit the mass-ratio corrections in conservative dynamics, and employ adiabatic approximation to include the radiation reaction. With the help of effective-one-body dynamics, we investigate the influence of mass-ratio corrections in the conservative part on the gravitational waves. We find that for the extra-relativistic orbits, the mass-ratio corrections can produce obvious orbital dephasing even for a very small mass ratio and then affect the waveforms. More importantly, it is noted that omitting the mass-ratio corrections in waveform templates may induce a fake signal of deviation from general relativity.

We derive optimal estimators for the binned two-, three-, and four-point correlators of statistically isotropic tensor fields defined on the sphere, in the presence of arbitrary beams, inpainting, and masking. This is a conceptually straightforward extension of the associated scalar-field estimators [O. H. E. Philcox, Phys. Rev. D 107, 123516 (2023).], but upgraded to include spin-2 fields such as cosmic microwave background polarization and galaxy shear, and parity-violating physics in all correlators. All estimators can be realized using spin-weighted spherical harmonic transforms and Monte Carlo summation and are implemented in the public code polybin, with computation scaling, at most, with the total number of bins. We perform a suite of validation tests verifying that the estimators are unbiased and, in limiting regimes, minimum variance. These facilitate general binned analyses of higher-point functions, and allow constraints to be placed on various pheomena, such as nonseparable inflationary physics (novelly including polarized trispectra), nonlinear evolution in the late Universe, and cosmic parity violation.

We study the neutral pion mass in the presence of an external arbitrary magnetic field in the framework of the linear sigma model coupled to quarks to a quark at finite temperature. In doing so, we have calculated the pion self-energy, constructed the dispersion equation via resummation, and solved the dispersion relation at zero three-momentum limit. In calculating the pion mass, we have included meson self-coupling’s thermal and magnetic contribution and approximate chiral order parameter $v_0$. We report that the ${\pi }^0$ mass decreases with the magnetic field and increases with temperature.

Deep neural networks (DNNs) are a powerful and flexible tool for information extraction and modeling. In this study, we use DNNs to extract the Sivers functions by globally fitting semi-inclusive deep inelastic scattering (SIDIS) data. To make predictions of this transverse momentum-dependent distribution, we construct a minimally biased model using data from COMPASS and HERMES. The resulting Sivers function model, constructed using SIDIS data, is also used to make predictions for Drell-Yan kinematics specific to the valence and sea quarks, with careful consideration given to experimental errors, data sparsity, and complexity of phase space.

Rapid rotation may exist in physical systems such as noncentral heavy ion collisions and neutron stars. Using functional renormalization group analysis of the quark-meson model, we investigate how rotation will affect chiral condensate. Our results show that rotation suppresses the chiral condensate at nonzero temperature. In comparison with mean field calculation, the rotational effect is weakened due to the inclusion of quantum fluctuation. We find that the transition in the $T\text{−}\mathrm{\Omega }$ diagram is always a crossover due to the causality constraint. Our results confirm previous studies conducted with other model calculations and shed light on the importance of boundary conditions in the infrared region of the theory. We also discuss the periodicity of chiral condensate under imaginary rotation and the necessary condition for analytic continuation to real rotation.

A holographic conformal field theory is dual to semiclassical general relativity in anti–de Sitter space coupled to matter fields. If the conformal field theory (CFT) factorizes in the large-$N$ limit, then all couplings in its dual are suppressed by the Planck scale, making the matter fields weakly interacting. We propose a mechanism to produce CFTs whose dual matter fields couple weakly to gravity, but interact strongly with each other. We achieve this by turning on exactly marginal multitrace deformations, and quantify the effect using conformal perturbation theory.

According to general relativity, the generic early Universe dynamics is chaotic. Various quantum-gravity effects have been suggested that may change this behavior in different ways. Here, it is shown how key mathematical properties of the classical dynamics can be extended to evolving quantum states using quasiclassical methods, making it possible to apply the established dynamical-systems approach to chaos even to quantum evolution. As a result, it is found that quantum fluctuations contribute to the reduction of the primordial chaos in early Universe models.

We suggest that “$G$ objects” recently discovered in the Galactic Center may be clouds of gas bound by the gravitational field of stellar-mass black holes produced in the interactions of sublunar primordial black holes with neutron stars. If dark matter is composed of primordial black holes with masses $({10}^{-16}–{10}^{-10})M_{\odot }$, these black holes can be captured by neutron stars in the Galactic Center, where the dark matter density is high. After the capture, the neutron star is consumed by the black hole, resulting in a population of $(1-2)M_{\odot }$ black holes. These stellar-mass black holes, accompanied by gaseous atmospheres, can account for the observed properties of the $G$ objects, including their resilience to tidal disruption by the supermassive black hole in the Galactic Center, while also producing emission consistent with inferred luminosities.

We analyze the amplitudes of one highly excited string (HES) state with two or three tachyons in open bosonic string theory. We argue that these processes are chaotic by showing that the spacing ratios of successive peaks in the angular dependence of the amplitudes are distributed as predicted by the $\beta$-ensemble of random matrix theory (RMT). We show how the continuous parameter $\beta$ depends on the level and helicity of the scattered HES state. We derive the scattering amplitude of an HES and three tachyons and show that it takes the form of the Veneziano amplitude times a dressing factor, and that the dressing is chaotic as a function of the scattering angle, in the sense that its spacing ratios match with RMT predictions.

We examine the black hole solutions of ${\mathrm{dS}}_3$ gravity by applying the explicit ${\mathrm{dS}}_3/{\mathrm{CFT}}_2$ correspondence. The gravity theory is described by Chern-Simons theory with complex gauge group $\mathrm{SL}(2,\mathbb{C})$, and the complexified theory is known to have too many saddle points. We determine the set of “allowable geometry” from dual conformal field theory correlators. Concretely, we classify the possible complex solutions corresponding to ${\mathrm{dS}}_3$ black holes from Liouville two-point functions. We extend the analysis to Liouville multipoint functions and among others we study geometry corresponding to two linked Wilson loops on $S^3$ by the monodromy matrix of Liouville four-point function. Some parts of the results were presented in a previous letter but here they are explained in more details and extended in various ways. In particular, we generalize the results to the case with higher-spin gravity by focusing the effects of higher-spin charges.

We introduce new techniques for calculations in gauge theories with extended supersymmetry. We are working in projective superspace where the $SU(2)$ R-symmetry is realized geometrically by including an auxiliary ${\mathbb{CP}}^1$ component in the superspace. Different gauge representations are associated with different dependence on the ${\mathbb{CP}}^1$ coordinate $\zeta$ and using contour integrals on ${\mathbb{CP}}^1$ we define natural projection operators on these different representations which leads to elegant formulas for all relevant objects. The new techniques lead to compact expressions for Lagrangians and field strengths in terms of the gauge prepotential but also to effective ways of reducing superspace expressions to components, i.e. to write them in terms of fields transforming covariantly only under a subgroup of the supersymmetry group. We illustrate our findings in several examples in three and four dimensions.

We develop a Lagrangian quantization formalism for a class of theories obtained by the restriction of the configuration space of gauge fields from a wider (parental) gauge theory. This formalism is based on application of the Batalin-Vilkovisky technique for quantization of theories with linearly dependent generators, their linear dependence originating from a special type of projection from the originally irreducible gauge generators of the parental theory. The algebra of these projected generators is shown to be closed for parental gauge algebras closed off shell. We demonstrate that new physics of the restricted theory, as compared to its parental theory, is associated with the rank deficiency of a special gauge-restriction operator reflecting the gauge transformations of the restriction constraints functions—this distinguishes the restricted theory from its partial gauge fixing. As a byproduct of this technique a workable algorithm for the one-loop effective action in generic first-stage reducible theory was constructed, along with the explicit set of tree-level Ward identities for gauge field, ghost, and ghosts-for-ghosts propagators. The formalism is applied to unimodular gravity theory, and its one-loop effective action is obtained in terms of functional determinants of minimal second-order operators, calculable on generic backgrounds by Schwinger-DeWitt technique of local curvature expansion. The result is shown to be equivalent to Einstein gravity theory with a cosmological term up to a special contribution of the global degree of freedom associated with the variable value of the cosmological constant. The role of this degree of freedom in a special duality relation between Einstein theory and unimodular gravity is briefly discussed.

We discuss generalized baby Skyrmions emerging in a ($1+2$)-dimensional $\sigma$ model with a certain Lie-algebraic structure. The same result applies to the Polyakov-Belavin instantons in $D=1+1$. The O(3) symmetry of the target space is lost, but O(2) is preserved in the simplest model under consideration. Both the topological charge and the soliton mass (the instanton action) are determined. Of special interest are limiting cases of the deformation parameter $k$ (also referred to as the elongation parameter). If $|k-1|\ll 1$, we arrive at a model which is studied in condensed matter. If $k\gg 1$, we obtain the so-called cigar, or sausage, model well-known in little string theory. If $k=1$, we return to CP(1). The deformed model under consideration interpolates between CP(1) and the cigar model. In $D=2$ we calculate the coupling constants renormalization at one loop. At $k\ge 1$ this class of models is asymptotically free in the ultraviolet limit and enters the strong coupling domain in the infrared. Also, in the infrared $k\to 1$ [i.e., we recover CP(1)].

We study the vacuum zero point energy associated to a scalar field with an arbitrary mass and conformal coupling in a dS background. Employing dimensional regularization scheme, we calculate the regularized zero point energy density, pressure and the trace of the energy momentum tensor. It is shown that the classical relation $⟨T⟩=-4⟨\rho ⟩$ for the vacuum stress energy tensor receives anomalous quantum correction which depends on the mass and the conformal coupling while the relation $⟨\rho ⟩=-⟨P⟩$ does hold. We calculate the density contrast associated to the vacuum zero point energy and show that $\delta \rho \sim ⟨\rho ⟩$ indicating an inhomogeneous and nonperturbative distribution of the zero point energy. Finally, we calculate the skewness associated to the distribution of the zero point energy and pressure and show that they are highly non-Gaussian.

Loops of inflationary gravitons are known to induce large temporal and spatial logarithms that can cause perturbation theory to break down. Nonlinear sigma models possess the same kind of derivative interactions and induce the same sorts of large logarithms, without the complicated index structure and potential gauge problem. Previous studies have examined models with zero field space curvature that can be reduced to free field theories by local, invertible field redefinitions. Here we study a model that cannot be so reduced and still shows the same sorts of large logarithms. We compute the evolution of the background at 1-loop and 2-loop orders, and we find the 1-loop $\beta$ and $\gamma$ functions.