Unified remnant models for aligned-spin, precessing, and eccentric binary black hole mergersUsing approximately 5000 numerical-relativity (NR) simulations spanning mass ratios up to q=128 and 1200 black-hole-perturbation-theory (BHPT) simulations extending to q=1000, we present…Tousif Islam, Digvijay Wadekar, Gaurav Khanna·Aug 2, 2026SaveLearn
Dynamics of a relativistic discrete body: rigidity conditions, and covariant equations of motionRigidity conditions for a body considered as a discrete system of relativistic particles are proposed. They by themselves do not yet determine an evolution of the system, and some second-order…Alexei A. Deriglazov·Aug 2, 2026SaveLearn
Motion of extended fluid bodies in the Newtonian limit of f(R) gravityIn the Newtonian limit of f(R) gravity, for an isolated self-gravitating system consisting of N extended fluid bodies, the inter-body dynamics are studied by applying the symmetric and trace-free…Bofeng Wu, Xiao Zhang·Aug 2, 2026SaveLearn
A Simple Pendulum in Schwarzschild SpacetimeWe determine the small-oscillation period of a simple pendulum in Schwarzschild spacetime. After transients decay, the displaced rope coincides with a geodesic of the induced spatial metric. This…Andrzej Czarnecki, Andrew Czezowski·Aug 1, 2026SaveLearn
Quintessence Dynamics of Generalized Holographic Ricci Dark Energy in f(T) Gravity: Stability, Phase-Space Attractor, and Statefinder AnalysisThe cosmological dynamics of generalized holographic Ricci dark energy (GHRDE) of Xu type, embedded within power-law f(T)=αT+βTm teleparallel gravity and driven by…S. V. Gore, A. Y. Shaikh, S. M. Shingne et al.·Aug 1, 2026SaveLearn
Evading Cauchy horizon excision in scalarized regular black holesSpontaneous scalarization provides a dynamical mechanism to evade the no-hair paradigm, but it has been argued to generically eliminate the Cauchy horizon in charged black holes. We show that this…Ernesto Contreras, Pedro Bargueño, Arthur G. Suvorov·Aug 1, 2026SaveLearn
Convexity criterion and radial-profile response for off-shell Kerr geometries: a fuzzy-dark-matter profile as an analytic benchmarkWe establish a sufficient one-minimum criterion for the off-shell Kerr family Δ(r) = r2 - 2rm(r) + a2 with a positive, nondecreasing mass profile m(r), showing that $1 - 2m'(r) -…Jingxu Wu, Jie Shi, Liangyu Luo·Aug 1, 2026SaveLearn
Filling the Shadow: A Propositional Model of Gravastar Accretion in f(R, Lm, T) GravityWhile General Relativity remains our most rigorously tested framework for gravitation, the theoretical persistence of singularities within standard black hole solutions continues to motivate the…Sandip Dutta·Aug 1, 2026SaveLearn
A rotating black hole in a Hernquist dark matter halo: horizon geometry, thermodynamics, and quantum emissionWe investigate the geometrical, thermodynamic, and quantum emission properties of a rotating black hole immersed in a Hernquist dark matter halo. Starting from a static black hole spacetime…A. A. Araújo Filho, Arun Kumar, N. Heidari et al.·Aug 1, 2026SaveLearn
New asymptotically flat gravitational instantonA new two-parameter asymptotically flat (AF) toric gravitational instanton is identified as a special case of the Euclidean double Kerr-NUT solution, by imposing certain symmetry and regularity…Edward Teo·Aug 1, 2026SaveLearn
A metric solution for rotating black holes embedded in dark matter halos with central spikesWe propose an analytic metric describing rotating black holes surrounded by generic dark matter halos. This metric is an exact solution of the field equations that incorporates a dark matter halo…Rui-Hong Yue, Yu-Qian Zhao, Wei-Liang Qian·Aug 1, 2026SaveLearn
Scalar memory from compact binary coalescencesGravitational memory provides a distinctive low-frequency probe of gravity, but explicit merger studies beyond general relativity remain limited. In this letter, we investigate memory from binary…Jann Zosso, Silvia Gasparotto, Llibert Aresté Saló et al.·Aug 1, 2026SaveLearn
Evolution of density perturbations in fractional cosmologyWe investigate the evolution of matter density perturbations within a fractional cosmological framework inspired by fractal space-time constructions in field theory, where a deformation of the…S. M. M. Rasouli·Aug 1, 2026SaveLearn
Bounce, Turnaround, and the Anisotropy Problem in Cyclic Cosmology on a Brane with a Timelike Extra DimensionWe study cosmological bounces, turnarounds, and cyclic evolution on an anisotropic Bianchi-I brane embedded in a five-dimensional bulk with a timelike extra dimension, within the…Rikpratik Sengupta, Arkajit Aich, Kaushik Bhattacharya·Aug 1, 2026SaveLearn
Primordial black hole dark matter from ultra-slow-roll inflation in Horndeski gravityPrimordial black holes (PBHs) provide a well-motivated non-particle candidate for dark matter, requiring an enhancement of curvature perturbations on small inflationary scales consistent with…Despina Totolou, Theodoros Papanikolaou, Emmanuel N. Saridakis·Aug 1, 2026SaveLearn
Trails of clouds in binary black holesSuperradiant instabilities of rotating black holes can give rise to long-lived bosonic clouds, offering natural laboratories to probe ultralight particles across a wide range of parameter space. The…Mateja Bošković, Rafael A. Porto, Matthias Koschnitzke·Aug 1, 2026SaveLearn
Kerr black holes with vector dark matter hairWe consider a massive vector-field perturbation on a Kerr black hole background. We fix the field's density at the edge of the black hole sphere of influence to model a bath of wave cold dark…Fredric Hancock, Helvi Witek·Jul 31, 2026SaveLearn
Stationary scalar clouds, quasinormal ringing, and observational signatures of (near-)extremal rotating Kalb-Ramond black holes: from the superradiant threshold to EHT boundsWe study a massive scalar field on the rotating Kalb-Ramond black hole of Kumar, Ghosh and Wang, in the (near-)extremal corner of its three-parameter family (a,γ,λ). We verify by direct…Gülnihal Tokgöz, İzzet Sakallı·Jul 31, 2026SaveLearn
How greedy is the Universe? An entropy ledger and a causal envelope for early black hole growthThe entropy of the observable Universe is dominated, by fifteen orders of magnitude, by the horizons of supermassive black holes, and gravitational collapse into black holes has often been proposed…Fernando Izaurieta, Cristian Quinzacara, Omar Valdivia·Jul 31, 2026SaveLearn
Can machine learning improve the detectability and disentanglement of the gravitational-wave background?Gravitational waves from compact binary coalescences and from early Universe processes are expected to form a gravitational-wave background. We employ a custom deep learning multi-scale multi-headed…Hugo Einsle, Marie Anne Bizouard, Tania Regimbau et al.·Jul 31, 2026SaveLearn
Optical Landscapes and High-Energy Collisions in Hairy Horndeski GravityWe investigate the null geodesic structure, photon sphere dynamics, and high-energy particle collisions within a class of static, spherically symmetric hairy Horndeski black holes. Characterized by…Filipe Cattete Alves, Rodrigo Maier·Jul 31, 2026SaveLearn
Resolution of Infrared Entanglement Divergences via the Extended Uncertainty PrincipleThe entanglement entropy of quantum systems typically exhibits both ultraviolet and infrared (IR) divergences. In the low-frequency limit, the IR divergence is intimately tied to the unbounded…Subhra Mondal, S. Shankaranarayanan·Jul 31, 2026SaveLearn
Deviation of trajectories in nonrelativistic and relativistic cases and Shirokov effectWe compare the deviations of circular orbits in the nonrelativistic and relativistic cases. General solutions of the deviation equations are obtained. We find the potentials for the nonrelativistic…Yu. V. Pavlov, V. P. Vandeev·Jul 31, 2026SaveLearn
The brachistochrone problem for a constant velocity traveler in static and spherically symmetric spacetimesThis work investigates the brachistochrone problem for a traveler with constant local velocity within static and spherically symmetric (SSS) spacetimes. The brachistochrone trajectory (BT) equations…Longfei Wang, Junji Jia·Jul 31, 2026SaveLearn
Excitation region of Kerr black hole quasinormal modes from Stokes geometryWe investigate the excitation region of black hole quasinormal modes (QNMs) from both analytical and numerical perspectives. On the analytical side, we propose that the QNM excitation radius is…Naritaka Oshita·Jul 31, 2026SaveLearn