The role of tetraquark operators in studying the isodoublet strange $\kappa$ and isovector nonstrange $a_0(980)$ scalar mesons in lattice quantum chromodynamics (QCD) is examined using an ensemble with $m_{\pi }\approx 230\mathrm{MeV}$ and spatial extent $L$ such that $m_{\pi }L\approx 4.4$. Hermitian correlation matrices using both single-meson, meson-meson, and tetraquark interpolating operators are used to extract the spectrum of finite-volume stationary states in the appropriate symmetry channels. Hundreds of local and extended tetraquark operators are explored. Determinations of the spectrum in each channel are found to be unreliable without the inclusion of at least one tetraquark operator. For example, the inclusion of tetraquark operators with isospin $1/2$ and strangeness 1 quantum numbers reveals the existence of an additional energy level in the $K\eta$ subsystem below the $K\eta$ threshold. The implications of this on parametrizing the scattering $K$-matrix through a well-known quantization condition to extract properties of the $\kappa$ and $a_0(980)$ scalar meson resonances are discussed.

In this paper, we propose a novel approach to investigate exotic hadronic states. For the $D{D}^{*}$ system, we employ the projection operator method to derive the momentum-space interaction potential. Subsequently, the complex momentum representation (CMR) method is adopted to realize a unified description of bound states, resonant states, and the continuum. By combining the Green’s function and the CMR, the scattering phase shifts and cross sections are determined. This integrated approach provides a comprehensive framework for analyzing the scattering dynamics of the $D{D}^{*}$ system. In the hadronic molecular state framework, the $X(3872)$, $T_{cc}^{+}$, and $Z_c(3900)$ states can be consistently explained as bound states, while the $G(3900)$ can be interpreted as a $P$-wave resonant state. The decomposition of the scattering phase shifts and cross sections facilitates understanding the roles of the resonant and continuum spectrum.

Recoil corrections, which appear at order $\mathcal{O}(\frac{1}{M})$, turn out to be crucial for the pentaquark molecules with heavy flavor. In the past, such corrections were typically regarded as negligible for the formation of molecular states. However, our research manifests their important impacts on the spectra of possible baryon-meson bound states. In certain cases, the binding energy sharply decreases after considering the recoil corrections. Using the one-boson-exchange model, we have studied a series of double heavy and hidden heavy pentaquark states with an SU(3) antitriplet baryon, including ${\mathrm{\Xi }}_c{\overline{D}}^{(*)}$, ${\mathrm{\Lambda }}_c{\overline{D}}^{(*)}$, ${\mathrm{\Xi }}_c{D}^{(*)}$, ${\mathrm{\Lambda }}_c{D}^{(*)}$, along with their bottom analogues. Both the $S\text{−}D$ wave mixing effect and the recoil corrections are incorporated in the investigation. Our results indicate that such corrections, working against the stability of bound-sate solutions in certain isospin-singlet channels, cannot be ignored. For the ${\mathrm{\Xi }}_c\overline{D}$ and ${\mathrm{\Xi }}_{c}D$ systems with $I(J^P)=0({\frac{1}{2}}^{-})$, the ${\mathrm{\Xi }}_c{\overline{D}}^{*}$ and ${\mathrm{\Xi }}_c{D}^{*}$ systems, as well as their bottom counterparts, with $I(J^P)=0({\frac{1}{2}}^{-})$ and $0({\frac{3}{2}}^{-})$, and the ${\mathrm{\Lambda }}_b{\overline{B}}^{*}$ system with $I(J^P)=\frac{1}{2}({\frac{1}{2}}^{-})$ and $\frac{1}{2}({\frac{3}{2}}^{-})$, although the bound-state solution can be found both with and without considering the recoil corrections, the inclusion of them weakens the attractive interaction of the molecular structures, as evidenced by smaller binding energies and larger root-mean-square radiuses in the refined results. This phenomenon is especially prominent in the ${\mathrm{\Xi }}_c{\overline{D}}^{*}$ and ${\mathrm{\Xi }}_c{D}^{*}$ systems.

Probing the internal organization of hidden-charm pentaquarks—including the spin-color correlations that distinguish compact diquark-diquark-antiquark configurations from loosely bound hadronic molecules—requires observables that go beyond mass spectroscopy. We argue that multicurrent QCD light-cone sum rules provide a diagnostic framework for this problem, not only through the expected sensitivity of the magnetic moment to the internal spin structure but, more importantly, through exact analytic relations among the flavor-sector contributions that are enforced by the algebra of the interpolating currents themselves. We identify two such signatures that emerge from our analysis of compact diquark-diquark-antiquark configurations: (i) for any of the four currents considered the light-quark contributions satisfy the exact ratio ${\mu }_u/{\mu }_d=e_u/e_d=-2$, reflecting a common Lorentz-color kernel that couples $u$ and $d$ only through their electric charges; and (ii) for the $J_3(x)$ current the charm-quark contribution vanishes identically, ${\mu }_c=0$, arising not from the pseudoscalar embedding of the charm diquark alone—since the same embedding occurs in $J_1(x)$, which yields a nonzero ${\mu }_c$—but from the specific Dirac structure associated with the anticharm coupling in the global current, which produces an analytic cancellation in the operator product expansion. We illustrate these signatures through explicit calculations using four independent diquark-diquark-antiquark interpolating currents $J_1(x)–J_4(x)$, assumed to carry $J^P={\frac{1}{2}}^{-}$, and obtain ${\mu }_{J_1}=-1.35_{-0.28}^{+0.35}{\mu }_N$, ${\mu }_{J_2}=3.14_{-0.50}^{+0.65}{\mu }_N$, ${\mu }_{J_3}=1.01_{-0.20}^{+0.25}{\mu }_N$, and ${\mu }_{J_4}=-1.79_{-0.34}^{+0.41}{\mu }_N$. These four predictions are then assigned to the observed $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ and $P_{\psi s}^{\mathrm{\Lambda }}(4459)$ resonances on the basis of the mass predictions of recent QCD sum rule analyses; we emphasize, however, that the corresponding $\pm 0.11\mathrm{GeV}$ mass uncertainties accommodate either state within $1\sigma$ of all four currents, so this current-to-state mapping is adopted only as an auxiliary phenomenological choice. The predicted magnitudes $|\mu |\sim 1–3{\mu }_N$ lie systematically above quark-model and heavy pentaquark chiral perturbation theory expectations ($|\mu |\lesssim 0.5{\mu }_N$). Applying the same flavor-decomposition procedure to two previous molecular LCSR analyses of the same states yields ${\mu }_u/{\mu }_d=-1/2$ rather than $-2$, providing an LCSR-internal contrast that operates at the flavor-decomposed level even when total magnitudes are comparable. Crucially, the two analytic signatures identified here are immune to the ambiguity of the state-to-current pairing and therefore offer falsifiable tests of the compact picture that survive the unavoidable phenomenological assumptions of mass-based assignments.

We perform a data-driven study of the doubly charmed tetraquark candidate $T_{cc}^{+}$. An ensemble of deep neural network classifiers, trained on synthetic amplitudes with controlled analytic structures, identifies a dominant pole topology characterized by an isolated pole on the $[bt]$ Riemann sheet which is robust against left-hand cut effects. A subsequent pole parameter extraction was performed via the uniformized $\mathcal{S}$-matrix and a complementary $\mathcal{K}$-matrix parametrization, which respectively provides a model-independent baseline and dynamical insight on the pole position and trajectory of the resonant state. Using this two-pronged approach, we submit that the $T_{cc}^{+}$ is a shallow $D^0{D}^{*+}$ bound state in the second Riemann sheet of the complex plane.

Neutrino-nucleus cross section measurements are critical for future neutrino oscillation analyses. However, our models to describe them require further refinement, and a deeper understanding of the underlying physics is essential for future neutrino oscillation experiments to realize their ambitious physics goals. Current neutrino cross section measurements provide clear deficiencies in neutrino interaction modeling, but almost all are reported averaged over broad neutrino fluxes, rendering their interpretation challenging. Using the concept of deep underground neutrino experiment-precision reaction independent spectrum measurement (DUNE-PRISM)—a movable near detector that samples multiple off axis positions—neutrino interaction measurements can be used to construct narrow virtual fluxes (less than 100 MeV wide). These fluxes can be used to extract charged-current neutrino-nucleus cross sections as functions of outgoing lepton kinematics within specific neutrino energy ranges. Based on a dedicated simulation with realistic event statistics and flux-related systematic uncertainties, but assuming an almost-perfect detector, we run a feasibility study demonstrating how DUNE-PRISM data can be used to measure muon neutrino charged-current integrated and differential cross sections over narrow fluxes. We find that this approach enables a largely model-independent reconstruction of powerful observables, including energy transfer, typically accessible only in electron scattering measurements, but that large exposures may be required for differential cross section measurements with few-percentage statistical uncertainties.

Using a sample of $(10087\pm 44)\times {10}^{6}J/\psi$ events collected with the BESIII detector, an improved measurement of the decay ${\eta }^{\prime }\to e^{+}{e}^{-}\omega$, with $\omega \to {\pi }^{+}{\pi }^{-}{\pi }^0$ and ${\pi }^0\to \gamma \gamma$ is performed. The branching fraction is determined to be $\mathcal{B}({\eta }^{\prime }\to e^{+}{e}^{-}\omega )=(1.79\pm 0.09\pm 0.12)\times {10}^{-4}$, where the first uncertainty is statistical and the second is systematic. This result is consistent with the previous measurement and is obtained with significantly improved precision. Furthermore, the first measurement of the transition form factor cutoff parameter for this decay is reported, with ${\mathrm{\Lambda }}^{-1}=(2.92\pm 0.83\pm 0.15){\mathrm{GeV}}^{-1}$. These measurements provide valuable input for understanding the internal structure of the ${\eta }^{\prime }$ meson and testing theoretical models.

We report a new measurement of transverse single-spin asymmetries for dijet production in collisions of polarized protons at $\sqrt{s}=200\mathrm{GeV}$. Correlations between the proton spin and the transverse momenta of its partons, each perpendicular to the proton momentum direction, are probed at high $Q^2\approx 160{\mathrm{GeV}}^2$. Evidence for nonzero Sivers effects is measured for the first time in dijets from proton-proton collisions, but only when the jets are sorted by their net charge, which enhances the otherwise canceling opposite-sign $u$- or $d$-quark contributions to separate data samples. The resulting asymmetries are compared to recent theoretical calculations. Separately, the associated Sivers observable $⟨k_T⟩$, the average parton transverse momentum, is extracted using a simple kinematics approach which further enables a determination of the individual partonic contributions to the observed asymmetries.

A two-parameter class of higher-dimensional, strongly coupled, confining field theories in the presence of magnetic fluxes for two Abelian gauge groups admits a top-down, holographic dual description. The corresponding two-parameter family of regular background solutions of the classical equations of maximal supergravity in seven dimensions descends from maximal supergravity in 11 dimensions. We study the global and local stability properties of these solutions. We identify lines of zero-temperature first-order phase transitions, describing a polygon (a square) in the space of parameters, identified with the two fluxes. The transition separates the family of gravity solutions dual to confining theories, inside the polygon, from those outside, in which the field theory is realized in a conformal phase. In the spectrum of fluctuations of the supergravity equations, interpreted as bound states of the dual, confining field theories, we find no evidence of local instabilities (tachyons). Over a significant portion of parameter space, that extends far away from the proximity to the transition, we identify an approximate dilaton, the mass of which is one order of magnitude smaller than the scale set by confinement. Our findings complement those emerging in other holographic models discussed in the literature, in which either the dilaton mass is only mildly lower than the confinement scale (when approaching a first-order transitions), or parametrically suppressed (when reaching the proximity to a second-order one).

Among the various applications of the AdS/CFT correspondence in condensed matter physics, the realization of the phase transition between the normal and superconducting phases in holographic quantum field theory is of particular importance. Following seminal papers on holographic superconductors that introduced the basic framework, one major line of development has focused on capturing the Meissner effect with all relevant parameters, which requires the inclusion of an external magnetic field. Although a complete holographic description of a superconductor is still lacking, the basic elements of the gravitational systems dual to what can most accurately be characterized as a charged superfluid have been established. Using holographic setups to describe three- and four-dimensional superconductors, we investigate the effect of noncommutative twist deformation of bulk fields on the phase transition parameters, such as the critical magnetic field. In a broader context, our results represent the first systematic attempt to elucidate the role of noncommutative gauge field theory as part of the bulk description of condensed matter systems.

The integration of high-energy degrees of freedom along the renormalization group (RG) flow in Poincaré-invariant theories is captured by a monotonic $c$-function. For such theories, holographic $c$-functions have been constructed using entanglement entropy. However, in theories with broken Lorentz invariance, these constructions generally fail, reflecting both the violation of entanglement RG monotonicity and its limitations in capturing essential features of nonrelativistic RG flows. Since many quantum many-body systems lack Lorentz invariance, it is important to identify a quantity that captures the decrease of effective degrees of freedom along such flows. We show that the recently introduced holographic timelike entanglement entropy naturally gives rise to a new $c$-function applicable to all such theories, which moreover obeys a geometric upper bound on its rate of change. We further demonstrate the existence of this $c$-function in theories with Lifshitz and hyperscaling-violating fixed points, showing that, provided the null energy condition and thermodynamic stability are satisfied, it obeys the expected RG monotonicity.

We study the critical behavior of the semi-infinite Gross-Neveu-Yukawa model, a quantum field theory describing Dirac fermions interacting with bosonic fields via a Yukawa coupling. We consider Neumann and Dirichlet boundary conditions for the bosonic fields, and the most general boundary conditions for the fermions that preserve unitarity, conformal invariance, and charge conjugation symmetry. We analyze the phase diagram and identify distinct fixed points corresponding to different universality classes of boundary critical behavior. The associated boundary critical exponents, which govern the scaling behavior and crossover phenomena, are computed to one-loop order. We also discuss the relevance of our results to the semi-infinite pseudoscalar Yukawa model.

We consider a self-gravitating, rigidly rotating charged perfect fluid immersed in the Wald magnetosphere, constructed out of two linearly independent Killing vectors present in stationary and axially symmetric spacetimes. We show that in nonvacuum spacetimes, Wald’s solution can be compatible with the electric current associated with a rotating charged perfect fluid characterized by the vanishing electric conductivity. We prove that for rigidly rotating fluids with a constant energy density or described by the polytropic equation of state, the resulting equations expressing the conservation of the energy-momentum tensor can be integrated. Consequently, the system can be described by nearly standard Einstein-Euler equations known from the theory of general-relativistic rotating fluids, with modifications introduced in the Euler-Bernoulli equation. Numerical solutions of the Einstein-Euler equations are provided for these two cases by introducing suitable modifications in the pseudospectral code by Ansorg, Kleinwächter, and Meinel.

The phase evolution of gravitational waves encodes critical information about the orbital dynamics of binary systems. In this work, we test the robustness of parametrized tests against unmodeled deviations from general relativity. We demonstrate that these parametrized tests are flexible and sensitive in detecting generic deviations in the waveform using the Cutler-Vallisneri bias formalism. This universality arises from examining the inherent geometry of the waveform signal and understanding how biases manifest. We show how Bayes factors are governed by the intrinsic geometry of the waveform signal manifold when parametrized tests are used to approximate generic violations of GR. We use the singular value decomposition to propose templates that are orthogonal to parametrized tests, identifying degeneracies and enhancing the detection of potential deviations. More broadly, the geometric framework developed here clarifies—at a fundamental level—how subtle waveform effects (including orbital eccentricity, spin precession, waveform systematics, and instrumental glitches) can mimic one another in data, and when they are intrinsically distinguishable.

The detection of gravitational waves from compact binary coalescences has provided significant insights into our Universe, and the discovery of new and unique gravitational wave candidates from independent searches remains an ongoing field of research. In this work, we built a hybrid search pipeline that combines matched filtering and deep learning to identify stellar-mass binary black hole candidates from detector strain data. We first present results from a targeted injection study to benchmark the sensitivity of our method and compare it with existing search pipelines. We demonstrate that our hybrid approach has comparable sensitivity for injections with a source-frame chirp mass greater than $25M_{\odot }$, and below this threshold our sensitivity drops off for signals with a network SNR less than 15. We also observe that our search method can identify a significant population of unique candidates. Furthermore, we conduct an offline search for gravitational wave candidates in the third observing run of the LIGO-Virgo-KAGRA Collaboration (LVK), yielding 31 candidates previously reported by the LVK with a probability of astrophysical origin $p_{\text{astro}}\ge 0.5$. We identify two other candidates: one previously reported only in a search conducted by the Institute for Advanced Study, and one previously unreported promising new candidate with a $p_{\text{astro}}$ of 0.63. This unique candidate has a high chirp mass and a high probability that the primary black hole is an intermediate-mass black hole.

We revisit an analytical approximation scheme for computing nonlinearity ratios involving quadratic quasinormal modes (QQNMs). We compute these ratios for the general case when the QQNM is not one of the linear QNMs, for the $(l,m)$ channel $(2,2)\times (2,2)\to (4,4)$. We find an excellent match with numerical simulations. We also discuss where and why the method can fail, for example, for the channel $(2,0)\times (2,0)\to (2,0)$, where we can only get crude estimates for the nonlinearity ratio. Motivated by recent studies on nonlinear ringdown at the horizon, we also compute the nonlinearity ratios at the horizon. We find that the ratio both at the horizon and infinity is insensitive to different choices of regularization of the source term in the second-order perturbations. We also discuss amplitudes of QQNMs sourced by linear overtones. Finally, we discuss the issues that must be resolved within this method to do precision analysis of nonlinear ringdown.

We study a minimal modified gravity scenario in the symmetric teleparallel (nonmetricity) formulation, focusing on an inverse nonmetricity term with $f(Q)=Q+M^4{Q}^{-1}$. The model does not introduce additional free parameters relative to the standard cosmological model $\mathrm{\Lambda }\mathrm{CDM}$, but modifies the late-time expansion and linear growth via an enhanced effective gravitational coupling. We identify key signatures: an enhanced matter power spectrum and cosmic microwave background (CMB) lensing, alongside a reduced late-time integrated Sachs-Wolfe effect and a shift in CMB peak positions. We confront the model with CMB data alone and in combination with baryon acoustic oscillations, redshift-space distortions, supernovae Ia, and DES large-scale structure data, considering both fixed minimal neutrino mass and varying $\mathrm{\Sigma }{m}_{\nu }$. We find that the model typically prefers higher $H_0$ than $\mathrm{\Lambda }\mathrm{CDM}$, alleviating the $H_0$ tension, while its boosted growth tends to increase clustering amplitudes unless offset by larger neutrino masses when $\mathrm{\Sigma }{m}_{\nu }$ is free. Overall, CMB-only data provide at most weak statistical support compared to $\mathrm{\Lambda }\mathrm{CDM}$, whereas late-time measurements impose tight restrictions that largely remove any improvement, positioning this model as a minimal yet strongly constrained alternative to dark energy.

$\delta N$ formalism is a useful method to calculate the curvature perturbation on superhorizon scales. Contrary to what it is typically done in the literature, we reformulate the $\delta N$ formalism by using the $e$-folding number $n$ counted forward in time. For a fixed initial time ${\overline{n}}_0$, the probability density function (PDF) of the field perturbation $\delta {\varphi }_0$ and its velocity $\delta {\pi }_0$ are specified by the solutions of the perturbation equation on subhorizon scales. As $\delta {\pi }_0$ is fully correlated with $\delta {\varphi }_0$ soon after horizon exit, we find a novel $\delta n$ formalism to calculate the curvature perturbation as well as its PDF. It can naturally incorporate those trajectories for which inflation never ends, which are lost when counting $N$ backward in time.

Leptophilic sub-MeV spin-1 dark matter (DM) can be converted into a photon via inelastic scattering with a free electron or absorption by a neutral hydrogen atom in the primordial plasma. We study for the first time the impact of the energy injection resulting from such processes on cosmic microwave background (CMB) anisotropies. We obtain upper limits on the vector and axial-vector DM-electron couplings using Planck 2018 temperature, polarization, and lensing data for DM masses between 100 eV and 100 keV. We find that, due to the suppression of the hydrogen atomic form factor at high energies, inelastic scattering provides the dominant constraint for DM masses above the keV scale. At lower masses, hydrogen ionization through DM absorption is the leading channel, driven by the higher efficiency of postrecombination energy injection in modifying the free-electron fraction. Although the bounds we derive are considerably weaker than existing laboratory and astrophysical limits, they provide a robust and independent cosmological probe of leptophilic DM interactions.