Center-vortex surfaces are mapped out in four dimensions within the framework of SU(3) lattice gauge theory to understand the role of secondary loops that develop in three-dimensional visualizations of center-vortex structure, appearing separate from the percolating cluster. Loops that initially appear disconnected in three-dimensional slices can originate from the same connected surface in four dimensions depending on the surface’s curvature. For the first time, these secondary loops are identified as “connected” or “disconnected” with respect to the vortex sheet, allowing new insight into the evolution of center-vortex geometry through the finite-temperature phase transition. At low temperatures, we find that secondary loops of any length primarily lie in the same sheet percolating the four-dimensional volume. Only a handful of small secondary sheets disconnected from the percolating sheet are identified. Above the phase transition, the vortex structure is still found to be dominated by a single large sheet but one that has aligned with the temporal dimension. With the near absence of any curvature orthogonal to the temporal dimension, connected secondary loops become vanishingly rare. Other novel quantities, such as the four-dimensional density of secondary sheets and the sheet sizes themselves, are analyzed to build a complete picture of center-vortex geometry in four dimensions.

We analyze the gravitational form factors and mechanical properties of the nucleon, focusing both on some general issues, as well as on modeling with meson dominance. We show that the lattice QCD results for the nucleon gravitational form factors at $m_{\pi }=170\mathrm{MeV}$, available for spacelike momentum transfer squared up to 2 GeV, are explained in a natural way within the meson dominance approach. We carry out the proper Raman spin decomposition of the energy-momentum tensor and in each spin channel use a minimum number of resonances consistent with the perturbative QCD short-distance constraints. These constraints are related to the superconvergence sum rules, following from the asymptotic perturbative QCD falloff of the form factors. The value of the nucleon $D$-term following from the fits is $-3.0(4)$. Next, we obtain the two-dimensional transverse gravitational densities of the nucleon in the transverse coordinate $b$. With the superconvergence sum rules, we derive new sum rules for these densities at the origin and for their derivatives, involving logarithmic weighting in the corresponding spectral density integrals. From analysis of the threshold behavior in the timelike region and the properties of the $\pi \pi \to N\overline{N}$ reaction, we infer the behavior of the transverse densities at asymptotically large coordinates. We also carry out the meson dominance analysis of the two- and three-dimensional mechanical properties of the nucleon (the pressure and stress) and explore their connection to the spectral densities via dispersion relations.

Recent high-precision $e^{+}{e}^{-}\to c\overline{c}$ data from BESIII and Belle are highly useful to understand vector charmonium ($\psi$) pole structures and puzzling line shapes due to the exotic hadron candidates $Y$. We, thus, perform a global coupled-channel analysis of most of the available data (ten two-body, nine three-body, and one four-body final states) in $\sqrt{s}=3.75-4.7\mathrm{GeV}$. Not only cross sections, but also invariant-mass distributions of subsystems are fitted. The $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}$ cross sections are also predicted. Our model includes dozens of (quasi-)two-body states that nonperturbatively couple with each other through bare $\psi$ excitations, particle-exchange, and short-range mechanisms; approximate three-body unitarity is considered. The amplitudes obtained from the fit are analytically continued to $\psi$ and $Z_c$ poles. We find $\psi$ states similar to those in the Particle Data Group listing and $Y(4320)$. Moreover, several $\psi$ states, including new ones, are found close to open-charm thresholds. Trajectories and compositeness of the near-threshold poles suggest dominant hadron-molecule contents in their internal structures. Two $Z_c$ poles are found as virtual states $\sim 40\mathrm{MeV}$ below the $D^{*}{\overline{D}}^{(*)}$ thresholds, consistent with lattice QCD results. This work presents the first global analysis to determine $\psi$ and $Z_c$ poles, thereby paving the way to extracting detailed properties of the prominent exotic hadron candidates from data.

We propose to probe light-quark dipole interactions at lepton colliders using the azimuthal asymmetry of a collinear dihadron pair $(h_1{h}_2)$ produced in association with another hadron $h^{\prime }$. This asymmetry, arising from quantum interference in the quark spin space, is exclusively sensitive to dipole interactions at the leading power of the new physics scale and simultaneously probes both the real and imaginary components of the dipole couplings. By combining all possible channels of $h^{\prime }$, this method allows for disentangling the up and down quark dipole moments and has the potential to significantly strengthen current constraints by one to two orders of magnitude.

Horizon brightened acceleration radiation (HBAR) signifies a unique radiation process and provides a promising framework in exploring acceleration radiation in flat/curved spacetime. Its construction primarily relies on the transition probability of an atom falling through a high-$Q$ cavity while interacting with a quantum field. The HBAR effect has typically been explored in the context of minimal coupling between the atom and the field amplitude. However, the minimally coupled models are affected by the infrared (IR) divergences that arise in the massless limit of the quantum fields in ($1+1$) dimensions. Thus, in the present manuscript, we examine the HBAR process using both the pointlike and finite size detectors coupled with the momentum of the field, which plays a crucial role in naturally resolving IR divergences. Our results suggest that the transition probability for the pointlike detector is independent of its frequency. This can be interpreted as the influence of the local gravitational field which modifies the sensitivity of the detector to its frequency and broadens its effective frequency range. Through a comparative study based on the length of the detector, we find that for a detector with a smaller length, the steady state solution for the density matrix of the field vanishes. This may indicate the existence of a nonequilibrium thermodynamic state under the condition of finite size detector-field interaction. These distinctive features are exclusive to the derivative coupling between the atom and the field, highlighting them as a compelling subject for future investigation.

Zajaček et al. made an interesting theoretical prediction on the electrification of a nonrotating black hole—if a nonrotating black hole is surrounded by plasma composed of protons and electrons, it will acquire electric charge due to the large difference of the inertial mass of a proton and that of an electron. Furthermore they revealed the effects of the electric charge of the black hole on the surrounding plasma. Since their results mainly rely on nonrelativistic analyses, we study the same subject through relativistic analyses in this paper. By investigating a test particle in the Schwarzschild spacetime, we find that if initial velocities of protons and electrons far from a black hole follow the Maxwell distribution, the black hole can acquire an electric charge whose value depends on the ratio of the temperature of the proton and that of the electron. We also show that if the black hole acquires the electric charge, the radii of the innermost stable circular orbit (ISCO) and the specific energy of a charged particle on the ISCO can be very different from those of a neutral particle. In contrast to the result obtained by Zajaček et al., we find that the ISCO radii of a proton and an electron are necessarily larger than that of a neutral test particle as long as the black hole acquires the charge. The large ISCO radius might lead to a larger angular diameter of a black hole shadow and a different estimate of the released energy due to the accretion of plasma from the estimate based on the assumption of electric neutrality of the central black hole.

Recently, a class of exact solutions describing rotating black holes immersed in a uniform magnetic field has been proposed, but various properties of such black holes remain unclear. This paper aims to explore how to extract energy based on the magnetic reconnection mechanism in both the circular orbit region and plunging region. After introducing the properties of this spacetime, we analyze physical quantities such as the size of the ergoregion, the event horizon, and the boundaries of the ergosphere. We then analyze the magnetic reconnection process within circular orbits. We plot energy-extraction parameter diagrams, and analyze the power and efficiency of energy extraction. The results show that the magnetic field impedes energy extraction. Compared with Kerr and Kerr-Melvin black holes, we find that this black hole’s energy-extraction capability is stronger than that of the Kerr-Melvin black hole but weaker than that of the Kerr black hole. Furthermore, we study magnetic reconnection and energy extraction in the plunging region of this black hole. The results indicate that the magnetic field still impedes energy extraction. The black hole’s energy-extraction capability in this region also remains weaker than that of a Kerr black hole but stronger than that of a Kerr-Melvin black hole. Comparing the plunging region with the circular orbit region, we find that the energy-extraction power in the plunging region is consistently stronger than in the circular orbit region.

Self-consistent solutions in Lorentz-violating gravity theories require the simultaneous satisfaction of: (i) the corresponding Einstein field equations, (ii) the matter field equations, and (iii) the Lorentz-violating field equations. Lorentz symmetry breaking can emerge spontaneously when tensor fields acquire nonzero vacuum expectation values. When frozen in these vacuum states, the dynamics of Lorentz-violating tensor fields may reduce to geometric constraints, potentially ruling out entire classes of compact objects. These constraints are crucial for ensuring physical consistency in Lorentz-violating frameworks, as they eliminate metric families incompatible with the preferred spacetime directions emerging from spontaneous Lorentz symmetry breaking. We investigate the criteria governing the emergence of these geometric constraints and analyze their consequences. Our analysis establishes a consistency framework for evaluating compact objects in these theories, demonstrating that several previously reported solutions in Lorentz-violating gravity models are physically inadmissible.

Spin-2 ultralight dark matter (ULDM) is a viable dark matter candidate and it can be constrained using gravitational wave (GW) observations. In this paper, we investigate the detectability of spin-2 ULDM by space-based GW interferometers. By considering a direct coupling between spin-2 ULDM and ordinary matter, we derive the corresponding response functions and sensitivity curves for various time-delay interferometry channels and calculate the optimal sensitivity curves for future millihertz GW detectors. Our results demonstrate that the space-based detectors can place stringent constraints on the coupling constant of spin-2 ULDM, reaching $\alpha \sim {10}^{-10}$ around a mass of $m\sim {10}^{-17}\mathrm{eV}$, surpassing current limits from ground-based detectors and pulsar timing arrays. Thus, the space-based GW detectors can serve as powerful tools not only for detecting GWs but also for probing fundamental properties of ultralight dark matter.

Gravitational wave (GW) memory, a permanent distortion of the space-time metric, is anticipated during the acceleration of relativistic jets in gamma-ray bursts (GRBs). While the precise mechanism behind GRBs is not yet fully understood, detecting GW memory may contribute to clarifying their nature. In this paper, we consider various scenarios of GW memory emission, including both single and multiple shells with thin and thick shells. In particular, the memory spectrum for each scenario is compared with the sensitivity of next-generation detectors, namely Deci-hertz Interferometer Gravitational-Wave Observatory and Einstein Telescope. Physical properties spread over a broad-band region, emphasizing the importance of combined and wide-band observations. We also simulate GW memory based on nearby, realistic scenarios and demonstrate its detectability.

Nonminimal coupling between the inflaton and the Ricci scalar plays a crucial role in shaping the predictions of single-field inflationary models. While a quartic potential with such coupling represents one of the simplest realizations compatible with cosmological observations, it generically receives important radiative corrections when the inflaton interacts with other fields, particularly those involved in the reheating process. In this work, we focus on radiative corrections arising from bosonic scalar couplings and study their impact on inflationary dynamics within the nonminimally coupled quartic potential framework. We demonstrate that bosonic corrections, unlike fermionic ones, yield predictions more compatible with the latest constraints from the Atacama Cosmology Telescope Data Release 6, especially when combined with Planck and BICEP/Keck data.We begin with a general model involving a gauge-singlet real scalar inflaton coupled to a complex scalar field, which could be the Standard Model Higgs or a GUT Higgs. As a concrete realization, we also investigate the case where the inflaton serves as a dark matter candidate through a Higgs portal interaction while highlighting its potential to generate observable levels of primordial gravitational waves. Only in the limit of a large nonminimal coupling, $\xi \gg 1$, do the inflationary dynamics of our model approximate those of the Starobinsky ${\mathcal{R}}^2$ model. However, due to the inclusion of inflaton-matter interactions, the two models are not strictly equivalent. Accordingly, we refer to the scenario studied here as a Starobinsky-like model. The inclusion of quantum corrections from scalar fields leads to characteristic imprints in the $(n_s,r)$ plane, allowing for refined constraints on scalar couplings from current and future observations.

Current and upcoming large-scale structure surveys place stringent requirements on the mitigation of observational systematics in order to achieve their unprecedented constraining power. In this work, we investigate the potential use of the spherical Fourier-Bessel (SFB) power spectrum in controlling systematics, leveraging its capability of disentangling angular and radial scales. We first clarify how the discrete SFB basis describes radial scales via the index $n$ and demonstrate that the SFB power spectrum reduces to the clustering wedge $P(k,\mu )$ in the plane-parallel limit, enabling it to inherit results from past literature based on the clustering wedge. While the parallel and perpendicular Fourier mode $(k_{||},k_{\perp })$ decomposition underlying the wedge is only valid for surveys of small angular coverage with a well-defined global line of sight, the SFB basis provides a natural generalization that can be applied to the full sky. Crucially, the separation of angular and radial scales allows systematics to be localized in SFB space. In particular, systematics with broad and smooth radial distributions primarily concentrate in the $n=0$ modes corresponding to the largest radial scales. This localization behavior enables one to selectively remove only particular angular and radial modes contaminated by systematics. This is in contrast to standard three-dimensional (3D) clustering analyses of wide-field surveys based on power spectrum multipoles, where systematic effects necessitate the removal of all modes below a given $k_{\min }$. Our findings advocate for adopting the SFB basis in 3D clustering analyses where systematics have become a limiting factor.

The tension between the Hubble constant ($H_0$) inferred from the cosmic microwave background (CMB) and that measured from late-time observations, such as the local distance ladder, is a major challenge in modern cosmology. Early dark energy (EDE) has been proposed as a possible resolution to the $H_0$ tension, but it typically worsens the $S_8$ tension by enhancing the small-scale matter power spectrum due to an increased cold dark matter density. To address this issue, we propose a model that combines EDE with an interacting dark energy-dark matter (iDEDM) scenario, and investigate whether this mixed model can simultaneously resolve both tensions. We find that the DE-DM interaction suppresses the growth of structure and reduces $S_8$, while EDE contributes to increase $H_0$, although less effectively than in the EDE-only case. Our Markov chain Monte Carlo analysis using Planck 2018, Dark Energy Spectroscopic Instrument (DESI) baryon acoustic oscillation, Dark Energy Survey (DES), Pantheon+, and SH0ES data shows that the mixed model provides modest improvements in both tensions, although it does not fully resolve either. This limitation appears to stem from the fact that both EDE and iDEDM independently favor a higher present-day matter density, which reduces the angular diameter distance and limits the degree to which EDE can lower the sound horizon.

We study the cosmological information contained in the cosmic web, categorized as four structure types: nodes, filaments, walls, and voids, using the Quijote simulations and a modified nexus+ algorithm. We show that splitting the density field by the four structure types and combining the power spectrum in each provides much tighter constraints on cosmological parameters than using the power spectrum without splitting. We show the rich information contained in the cosmic web structures—related to the Hessian of the density field—for measuring all of the cosmological parameters, and in particular for constraining neutrino mass. We study the constraints as a function of Fourier scale, configuration space smoothing scale, and the underlying field. For the matter field with $k_{\max }=0.5h/\mathrm{Mpc}$, we find a factor of $\times 20$ tighter constraints on neutrino mass when using smoothing scales larger than $12.5\mathrm{Mpc}/h$, and $\times 80$ tighter when using smoothing scales down to $1.95\mathrm{Mpc}/h$. However, for the $\mathrm{CDM}+\mathrm{baryon}$ field we observe a more modest $\times 1.7$ or $\times 3.6$ improvement, for large and small smoothing scales respectively. We release our new python package for identifying cosmic structures pycosmmommf to enable future studies of the cosmological information of the cosmic web.

We consider the evolution of linear matter perturbations in the context of the standard cosmological model ($\mathrm{\Lambda }\mathrm{CDM}$) and a phenomenological modified gravity model. We use the physics-informed neural network (PINN) bundle method, which allows to integrate differential systems as an alternative to the traditional numerical method. We apply the PINN bundle method to the equation that describes the matter perturbation evolution, to compare its outcomes with recent data on structure growth, $f{\sigma }_8$. Unlike our previous works, we can calculate a bound on the error of this observable without using the numerical solution of the equation. For this, we use a method developed previously by ourselves to calculate an exact bound on the PINN-based solution using only the outcomes of the network and its residual. On the other hand, the use of an updated data set allows us to obtain more stringent constraints on the plane ${\mathrm{\Omega }}_m-{\sigma }_8$ than previous works.

vela.jl is a package for performing Bayesian pulsar timing and noise analysis written in julia and python. In the wideband paradigm of pulsar timing, simultaneous time of arrival and dispersion measure measurements are derived from a radio observation using frequency-resolved integrated pulse profiles and templates without splitting the observation into multiple frequency sub-bands. We describe the implementation of the wideband timing paradigm in vela.jl, and demonstrate its usage using the NANOGrav 12.5-year wideband data of PSR $\mathrm{J}1923+2515$. vela.jl is the first software package to provide this functionality.

Ultraperipheral collisions (UPCs) of ions provide new opportunities to study the quarkonium production mechanism in photon-photon scattering. In this paper, we investigate the exclusive process $\gamma +\gamma \to J/\psi +\gamma$ up to $\mathcal{O}({\alpha }_s{v}^2)$ accuracy within the nonrelativistic quantum chromodynamics factorization framework. We evaluate the corresponding cross sections for Pb-Pb and p-p UPCs at the Large Hadron Collider. Numerical results show that the $\mathcal{O}({\alpha }_s)$, $\mathcal{O}(v^2)$, and $\mathcal{O}({\alpha }_s{v}^2)$ corrections are about $-50\%$, $-33\%$, and 15% of the leading-order (LO) contribution, respectively, showing reasonable convergence in both ${\alpha }_s$ and $v^2$ expansion. Collectively, these corrections suppress the LO cross section by a factor of about $1/3$, which is a crucial effect for reliable phenomenological analysis. Our results suggest that future experimental measurements of this process are feasible.

We discuss a minimal renormalizable Pati-Salam theory based on the $SU(4{)}_{\mathrm{C}}\times SU(2{)}_{\mathrm{L}}\times SU(2{)}_{\mathrm{R}}$ gauge group, with unification scale Higgs multiplets taken as $SU(2{)}_{\mathrm{L}}$ and $SU(2{)}_{\mathrm{R}}$ doublets, which lead to neutrino Dirac picture. Although a number of scalar particles could be light, even lying at the LHC energies, the unification scale is hopelessly out of reach in any foreseeable future. Moreover, phase transition in the early Universe leads to the production of magnetic monopoles and domain walls, both incompatible with the standard cosmological model. A small explicit breaking of the discrete left-right symmetry allows the domain walls to decay, and in the process possibly sweep away the monopoles, analogously to the previously discussed case of $SU(5)$ grand unified theory. This leaves an important imprint of gravitational waves, within the reach of next generation searches, correlated with monopole detection and new light particles at collider energies. The theory has a dark matter candidate in the form of an inert scalar doublet, with a mass below TeV, which can further trigger electroweak baryogenesis.

We study the complementarity between COHERENT and LHC searches in testing neutrino nonstandard interactions (NSIs) through the completion of the effective field theory approach within a $Z^{\prime }$ simplified model. Our results show that LHC bounds are strongly dependent on the $Z^{\prime }$ mass, with relatively large masses excluding regions in the parameter space that are allowed by COHERENT data and its future expectations. We demonstrate that the combination of low- and high-energy experiments results in a viable approach to break NSI degeneracies within the context of simplified models.