482 papers
This review explores how multi-messenger astronomy and diverse observational data across various scales constrain and probe extensions to the Standard Model and General Relativity, including dark matter candidates and modified gravity theories, to illuminate the nature of the dark sector.
This paper investigates the physical properties of accelerating Bertotti-Robinson black holes in a uniform magnetic field by analyzing their Hawking temperature, geodesic motion, orbital stability, photon sphere characteristics, and energy emission rates to determine how the acceleration and magnetic field parameters influence these phenomena.
This paper presents the first observational constraints on Luciano-Saridakis entropic cosmology using combined background data, demonstrating that the model provides a statistically robust fit to current observations and offers a viable extension to the standard CDM model with the potential to alleviate the Hubble tension.
This paper establishes a correspondence between the Extended Uncertainty Principle (EUP) and the Schwarzschild black hole metric to demonstrate that while the event horizon remains unchanged, increasing EUP parameters expand the photon sphere but shrink the shadow size, thereby allowing observational data from Sgr A* to constrain EUP parameters.
This paper investigates the quasinormal modes of a scalar field on a parity-violating rotating black hole background, deriving perturbative frequency corrections for low spins and revealing significant deviations from Kerr predictions in the near-extremal regime, thereby offering a new method to probe parity-violating gravity in strong gravitational fields.
This paper demonstrates that late-time de Sitter cosmological correlators can be efficiently computed and analyzed using a non-unitary Euclidean AdS Lagrangian, revealing that the theory's unitarity is encoded in the positivity of the spectral density rather than standard CFT constraints, with resonant features in this density offering potential signatures for experimental detection.
This paper constructs locally inertial and radially locked reference frames for geodesic observers in stationary axisymmetric dust spacetimes to analyze dust configurations via photon frequency shifts and establish a general relativistic framework for reconstructing spectroscopic and astrometric relative velocities in galactic kinematics.
This paper proposes a singularity-free model of gravitational collapse that replaces the standard Schwarzschild interior with a geometry supported by a cosmological-constant-like stress-energy tensor and a Higgs-like scalar field, resulting in a new theoretical mass-radius limit of while violating the local Principle of Equivalence through a metric sign change across the horizon.
This paper proposes and observationally constrains a novel "structure-induced" dark energy model, which links cosmic structure formation to dark energy evolution, demonstrating its viability as a solution to fine-tuning and coincidence problems while offering flexibility in addressing current cosmic tensions.
This paper establishes a systematic framework for identifying separability structures in stationary, axisymmetric spacetimes with matter fields, using a generalized metric ansatz to derive new rotating black hole and wormhole solutions.
This paper addresses the conceptual and technical challenges of defining operational reference frames and relational observables in gauge systems like General Relativity, particularly within a non-perturbative quantum field theory context, by deriving and exploring a general formula for relational reference frame transformations (RRFT) to clarify the relationship between gauge reduction, quantization, and physical interpretation.
This paper argues that we cannot empirically determine whether the universe had a beginning, demonstrating that common defenses of a cosmic origin rely on confirmation theory errors and that, due to extensions of the Malament-Manchak theorems, observers in almost all classical spacetimes cannot distinguish between models with a past singularity and those that are beginningless or lack the requisite time ordering.
This paper investigates non-minimally coupled scalar field inflation within Loop Quantum Cosmology with inverse-volume corrections, demonstrating that the model's predictions for inflationary observables align with current observational data while the non-minimal coupling significantly enhances the probability of achieving sufficient inflation by enlarging the favorable phase-space volume.
This paper defends the excursion-set formalism for deriving primordial black hole mass distributions by demonstrating that noise is strictly white when sampling on a synchronous surface and that cloud-in-cloud effects remain crucial for broad power spectra, thereby establishing the necessity of solving the first-passage-time problem with a moving barrier.
This paper establishes the existence of nonlinear wave operators and proves small-data asymptotic completeness for the Maxwell-Higgs system with scalar potential on subextremal Kerr spacetimes by constructing a gauge-invariant scattering map that relies on a transfer principle from linear estimates, provided the absence of superradiant instability.
This paper utilizes modern amplitude methods and a heavy-mass effective field theory to compute and resum the third post-Minkowskian gravitational scattering dynamics of spinning black holes, demonstrating that the resulting eikonal phase correctly reproduces the characteristic ring singularity of the Kerr metric.
This paper demonstrates that wave-optics effects induced by cold dark matter subhalos in the mass range of $10^410^7\,M_{\odot}$ produce detectable, percent-level frequency-dependent amplitude and phase distortions in strongly lensed gravitational waves within the LISA band, offering a novel probe of subgalactic dark matter structure inaccessible to electromagnetic observations.
This paper demonstrates that single-minus tree-level -graviton scattering amplitudes are nonvanishing for specific kinematic configurations, deriving a Berends-Giele recursion relation that simplifies to a product of soft factors in a restricted decay region and reveals a connection to a recursive Ward identity.
This paper proposes that Hermiticity in quantum mechanics is a symmetry arising from global inner product conservation, which becomes obstructed by causal horizons in black hole geometries, thereby inducing effective non-Hermitian dynamics that unify gravity, entropy production, and the generalized second law of thermodynamics.
This study demonstrates that neutron stars can gravitationally confine ghost scalar fields with negative kinetic energy, supporting stable equilibrium configurations that evolve into persistent, synchronized oscillations between the stellar fluid and the scalar field.