The factorization proposal claims that the codimension one “pinning defect,” on which a local relevant operator is integrated, factorizes the space into two halves in general conformal field theories in the infrared limit. In this paper, we study a two-dimensional long-range Ising model at criticality with a line defect or an interface, which physically corresponds to changing the local temperature on it. We show that in the perturbative regime, it is not factorizing even in the infrared limit. An intuitive explanation of the nonfactorization is that the long-range Ising model is equivalent to a local conformal field theory in higher dimensions. In this picture, the space is still connected through the “extra dimension” across the defect line.

We study nonequilibrium initial states of quantum fields in curved spacetime and develop a framework for describing global quenches as unitary perturbations of the initial density matrix. Using the Keldysh-Schwinger functional integral, we derive expressions for postquench correlators in arbitrary geometries and apply the method to both Minkowski and de Sitter backgrounds. In flat space, the approach reproduces the known relaxation behavior for massive fields and reveals qualitatively distinct dynamics in the massless case. In de Sitter space, we find that the late-time decay of quench-induced corrections depends sensitively on the mass and may influence the behavior of cosmological observables such as the power spectrum. The framework also extends straightforwardly to non-Gaussian initial states, providing a basis for future studies of loop effects and primordial non-Gaussianities.

We revisit the renormalization of the gauge coupling in massless QED coupled to a scaleless quadratic theory of gravity. We compare two alternative prescriptions for the running of the electric charge: (i) the conventional $\mu$ running in minimal subtraction, and (ii) a physical running extracted from the logarithmic dependence of amplitudes on a hard scale $Q^2$ (e.g., $p^2$ or a Mandelstam invariant) after removing IR effects. At one loop, using dimensional regularization with an IR mass regulator $m$, we compute the photon vacuum polarization. We find a clean separation between UV and soft logarithms: the former is gauge and process independent and fixes the beta function, whereas the latter encodes nonlocal, IR-dominated contributions that may depend on gauge parameters and must not be interpreted as UV running. In the quadratic-gravity sector, the photon self-energy is UV finite—the $\ln {\mu }^2$ pieces cancel—leaving only $\ln (Q^2/m^2)$ soft (IR) logs, which do not contribute to the running of the coupling once IR effects are consistently removed. Consequently, quadratic gravity does not modify the one-loop UV coefficient and thus does not alter $\beta (e)$. Therefore, the physical running coincides with the $\mu$ running in QED at one loop. Our analysis clarifies how to extract a gauge and process independent running in the presence of gravitational interactions and why soft logs from quadratic gravity should not contribute to $\beta (e)$.

Contextuality, a key resource for quantum advantage, describes systems in which the outcome of a measurement is not independent of other compatible measurements, in contrast to classical hidden-variable descriptions. We investigate the harvesting of contextuality from the vacuum of a quantum field using Unruh-DeWitt detectors. We show that localized interactions with the field can endow initially noncontextual detectors with contextuality with respect to Heisenberg-Weyl measurements, as quantified by contextual fraction. The harvested contextuality correlates with the emergence of Wigner function negativity, in agreement with known equivalences between these notions. Our results show that contextuality is a resource that can be extracted directly from the quantum vacuum and establish contextuality harvesting as a fundamental phenomenon in relativistic quantum information.

We have investigated the correspondence between quasinormal modes and greybody factors for the five-dimensional Schwarzschild-Tangherlini black hole. The quasinormal modes of gravitational perturbations are computed numerically using the continued fraction method. Particularly, we have analyzed the scalar, vector, and tensor types of perturbations, revealing that the tensor type only exists in spacetimes with more than four dimensions. Then, the greybody factors are calculated analytically via the correspondence using data from the fundamental quasinormal mode and the first overtone. Next, the greybody factors are computed independently using a numerical method. Notably, the results obtained from the two methods coincide, demonstrating that the correspondence holds with high accuracy for all three types of gravitational perturbations. Furthermore, our results extend the validity of the correspondence to the tensor type, which can only be tested in spacetimes with more than four dimensions.

Modified Einstein’s equations implementing both an energy-dependent Newtonian and cosmological constant can be obtained via a modified action characterized by a nonminimal gravity-matter coupling. We show how different dynamics for the high energy regime—that nevertheless have in common the vanishing of the Newton constant—result in models of gravitational collapse which source the formation of nonsingular geometries with different types of asymptotic core: de Sitter, Minkowski, and with “steep pressure.” As we categorise their defining properties, one feature, which we prove to be actually independent of both the specific form of the nonminimal coupling and the equation of state of the collapsing fluid, stands out: the formation of a geometry with Minkowski core occurs only if the Newton constant, before finally vanishing, assumes negative values.

The latest results from the Atacama Cosmology Telescope Collaboration have moved the preferred perturbation spectral index $n_{\mathrm{s}}$ closer toward one. We reanalyze constraints on the simplest version of the curvaton model, using $n_{\mathrm{s}}$ and the tensor-to-scalar ratio $r$. We show that in the massless curvaton case the model gives the same locus of $n_{\mathrm{s}}–r$ predictions as the power-law model $V(\varphi )\propto {\varphi }^p$, but with a different and more elegant physical interpretation. The model gives an excellent account of current observational data, both in the regime where the curvaton dominates the observed perturbations and with an admixture of inflaton-originated perturbations of up to about one third of the total. the addition of the newest South Pole Telescope SPT-3G D1 dataset maintains this conclusion in favor of the curvaton model. Forthcoming large-scale structure surveys, such as that of the recently launched SPHEREx probe, could discriminate between curvaton and single-field inflation models using the bispectrum.

Generalized axionlike scalar fields provide a well-motivated framework for describing the late-time acceleration of the Universe. As the field evolves, it rolls down its potential and, depending on its mass and initial conditions, it may either still be approaching the minimum or already oscillating around it. These two dynamical regimes require distinct treatments of cosmological perturbations. In this work, we perform a detailed analysis of linear cosmological perturbations in the regime where the dark-energy scalar field undergoes coherent oscillations about the minimum of its potential. We show that the standard effective fluid description breaks down in this phase and develop a consistent field-based perturbation framework, which we use to assess the impact of oscillatory dark energy on the growth of cosmic structures.

An empirical baryon density profile can be included in the Schrödinger-Poisson (SP) equations to influence the fuzzy dark matter (FDM) soliton formation. However, to probe the effects of baryon on the other dynamical evolutions of the FDM soliton, its equation of motion (EoM) inside the corresponding FDM soliton is needed. In this paper, given an empirical baryon density profile, we first provide the cylindrical symmetric FDM soliton solution about the FDM density and the total potential of FDM and baryon. Then, instead of EoM, we build an analytical emulator (AE) for the baryon density distribution from the obtained FDM density and total potential by machine learning. Finally, we check that this AE works as well as an empirical baryon density profile for the FDM soliton formation, with the fractional errors $\lesssim 0.04$. It should also work as a kind of baryon EoM for some other simple FDM soliton evolutions.

We develop a fully relativistic framework to study the rotational response of gravitationally coupled two-fluid neutron stars within the slow-rotation approximation. Treating the two components as independently conserved perfect fluids interacting only through spacetime curvature, we derive the coupled equilibrium and frame-dragging equations and exploit their linear structure to construct a basis decomposition of the rotational response. This formulation leads to a natural definition of the effective total moment of inertia, which generalizes the single-fluid concept and depends solely on the equilibrium background. It further reveals that the coupled system admits two intrinsic collective rotational eigenmodes, characterized by distinct eigenmoments of inertia, even in the absence of relative rotation between the fluids. Applying this framework to neutron stars containing dark matter, we explore how the presence of an additional gravitationally bound component modifies the global rotational response and its relation to tidal deformability. Our results demonstrate that the persistence or breakdown of rotational-tidal universality in two-fluid neutron stars is governed by dark-sector microphysics rather than by the mere presence of an additional component, and establish a unified framework for interpreting rotational observables, intrinsic mode structure, and universal relations in multicomponent relativistic stars.

Efficient searches for gravitational waves from compact binary coalescence are crucial for gravitational-wave observations. We present a proof-of-concept for a method that utilizes a neural network taking a signal-to-noise ratio map, a stack of signal-to-noise ratio time series calculated by the matched filter, as input and predicting the presence or absence of gravitational waves in observational data. We train the neural network with a data set of gravitational-wave signals from stellar-mass black hole mergers injected into stationary Gaussian noise. We use data set 1 of the mock data challenge MLGWSC-1 to assess the ability of the proposed algorithm. The estimated sensitivity distance is 2428.10 Mpc at the false alarm rate of 1 per month. These results indicate that our algorithm achieves reasonable sensitivity with practical computational resources.

We report on the cosmic ray mass composition measured by the Telescope Array Low-energy Extension (TALE) hybrid detector. The TALE detector consists of a fluorescence detector (FD) station with 10 FD telescopes located at the Telescope Array (TA) Middle Drum FD Station (itself made up of 14 FD telescopes), and a surface detector (SD) array of scintillators. The array consists of 40 SDs with 400 m spacing and 40 SDs with 600 m spacing. In this paper, we present results on the measurement of the depth of shower maxima ($X_{\max }$) in the energy range from ${10}^{16.5}\mathrm{eV}$ to ${10}^{18.5}\mathrm{eV}$ collected over five years of the TALE hybrid detector. The $X_{\max }$ distributions were analyzed and compared with Monte Carlo simulations of proton, helium, nitrogen, and iron primaries, using the QGSJet II-04 hadronic interaction model. Our results indicate that the elongation rate of the mean $X_{\max }$, which is defined as the slope of $⟨X_{\max }⟩$ versus cosmic ray energy, exhibits a break around ${10}^{17}\mathrm{eV}$. Up to this energy, the composition becomes increasingly heavy, characterized by a growing dominance of heavy nuclei and a steadily decreasing fraction of light primaries. Beyond this energy, the proton fraction increases significantly with energy. These findings suggest a transition from Galactic to extra-Galactic cosmic ray sources around the so-called second knee.

We use conformal symmetry to calculate the next to next to leading order (NNLO) anomalous dimension matrix (three loops) for flavor-singlet axial-vector QCD operators for spin $N\le 8$ from a set of gauge-invariant two-point correlation functions. Combining this result with the recent calculation of the two-loop coefficient functions, we carry out the calculation of the $\gamma {\gamma }^{*}\to \eta$ and $\gamma {\gamma }^{*}\to {\eta }^{\prime }$ form factors at large momentum transfers to the NNLO accuracy in perturbative QCD.

We study the lepton flavor conserving and violating couplings of a doubly charged scalar at a 3 TeV muon collider. Using a model-independent Lagrangian, we analyze the $ee$, $\mu \mu$, and $\tau \tau$ final states mediated by the doubly charged scalar to probe individual couplings to $\mu e$, $\mu \mu$, and $\mu \tau$. We find that for a doubly charged scalar of mass greater than 1 TeV and $\mathcal{O}(1)$ couplings, we achieve high signal significance in these channels. We delineate the collider’s sensitivity in the mass-coupling plane, highlighting the extensive reach of the muon collider in probing these couplings far beyond the current experimental limits. We also propose an angular distribution variable to discriminate between the exchange of a doubly charged scalar from that of a neutral scalar, which gives identical signals.

We study the nonmaximal symmetry breaking patterns of $\mathfrak{s}\mathfrak{u}(8)\to {\mathfrak{g}}_{531}/{\mathfrak{g}}_{351}$ allowed in a supersymmetric theory with the affine Lie algebra of $\widehat{\mathfrak{s}\mathfrak{u}}(8{)}_{k_U=1}$, which was recently proposed to explain the three-generational standard model quark/lepton mass hierarchies as well as the Cabbibo-Kobayashi-Maskawa mixing pattern. Three gauge couplings are found to achieve the unification below the Planck scales, according to the unification relations determined by the affine Lie algebra at a level of 1. We also prove that a separate nonmaximal symmetry breaking pattern of $\mathfrak{s}\mathfrak{u}(8)\to {\mathfrak{g}}_{621}$ is unrealistic due to the additional massless vectorlike quarks in the spectrum.

The postinflationary production of supermassive particles can have profound implications for the thermal history of the Universe and may leave observable imprints in the gravitational wave (GW) background. In scenarios where the inflaton couples predominantly to heavy fields, say right-handed neutrinos (RHNs), nonperturbative mechanisms such as parametric resonance can lead to their efficient production, even when their masses exceed the inflaton mass. Once produced, the RHNs emit gravitons through bremsstrahlung as they decay into the Standard Model (SM) particles via $N\to \ell +H$, enabled by the unavoidable minimal coupling to gravity, sourcing a stochastic GW background. We study this mechanism within the framework of $\alpha$-attractor inflationary models, highlighting how the resulting GW spectrum carries indirect imprints of the heavy sector and the postinflationary dynamics. This offers an observational window into otherwise inaccessible supermassive particles and provides a powerful probe of high-scale physics beyond the SM.

We have developed an extension of the inert doublet model in which the $CP$ phases in the weak sector are generated from one-loop level corrections mediated by dark fields, while the strong $CP$ phase remains vanishing at three loops. In this framework, the tiny masses of the active neutrinos are produced through a radiative inverse seesaw mechanism at a two-loop level, the masses of the first and second families of Standard Model (SM) charged fermions arise from a one-loop level radiative seesaw mechanism, and the third generation of SM charged fermion masses are generated at tree level. We have demonstrated that the proposed model successfully accounts for SM fermion masses and mixings. The radiative nature of the seesaw mechanisms is attributed to preserved discrete symmetries, which are required for ensuring the stability of fermionic and scalar dark matter candidates. The preserved discrete symmetries also allow for multicomponent dark matter, whose annihilation processes permit one to successfully reproduce the measured amount of dark matter relic abundance for an appropriate region of parameter space, which has been shown to be compatible with current dark matter direct detection limits. Besides that, we explore the model’s ability to explain the 95 GeV diphoton excess observed by the CMS Collaboration, showing that it readily accommodates this anomaly. We also have shown that charged lepton flavor violating decays acquire rates within the current experimental sensitivity.

We show how to construct Hamiltonian lattice theories with one exact supersymmetry on arbitrary triangulations of curved space in any number of dimensions. Both bosons and fermions satisfy discrete Kähler-Dirac equations. The quantization of the fermions proceeds by imposing conventional anticommutation relations while the bosons require a modification of the usual canonical commutator. On regular lattices we construct parity, time reversal and translation-by-one (shift) symmetries. We argue that the latter are generically noninvertible symmetries. We also show how to couple these degrees of freedom to background gauge fields which leads to a theory with enhanced supersymmetry.

We investigate the feasibility of extracting infinite volume scattering phase shift on quantum computers in a simple one-dimensional quantum mechanical model, using the formalism established in the work by Guo and Gasparian [Phys. Rev. D 108, 074504 (2023)] that relates the integrated correlation functions for a trapped system to the infinite volume scattering phase shifts through a weighted integral. The system is first discretized in a finite box with periodic boundary conditions, and the formalism in real time is verified by employing a contact interaction potential with exact solutions. Quantum circuits are then designed and constructed to implement the formalism on current quantum computing architectures. To overcome the fast oscillatory behavior of the integrated correlation functions in real-time simulation, different methods of postdata analysis are proposed and discussed. Test results on IBM hardware show that good agreement can be achieved with two qubits, but complete failure ensues with three qubits due to two-qubit gate operation errors and thermal relaxation errors.