Strong-deflection expansion of the deflection angle near a degenerate photon sphereWe present a strong-deflection expansion for the deflection angle of light rays scattered near a degenerate photon sphere in asymptotically flat, static, and spherically symmetric spacetimes. Our…Takahisa Igata, Tadashi Sasaki, Naoki Tsukamoto·May 13, 2026SaveLearn
Geodesic completion of big bangs from emergent geometryChaplygin gas and other k-essence models exhibit emergent geometry, with perturbations propagating on an acoustic metric disformally related to the Einstein-frame metric. For superluminal sound…Brooke Berrios, Cameron Corley, Sky O'Donnell et al.·May 13, 2026SaveLearn
The Emergence of Measured Geometry in Self-Gravitating SystemsThis work investigates the geometrical properties of self-gravitating N-body systems from the perspective established by Henri Poincaré and Albert Einstein concerning the operational nature of…Maria I. R. Lourenço, Julian Barbour, Francisco S. N. Lobo·May 13, 2026SaveLearn
Radial Oscillations of Neutron Stars with Vector-Induced Scalar HairIn this paper, we investigate the equilibrium configurations and radial perturbations of neutron stars within a subclass of gauge-invariant Scalar-Vector-Tensor (SVT) theories. By solving the…Hamza Boumaza·May 13, 2026SaveLearn
Modeling the frequency-domain ringdown amplitude of comparable-mass mergers with greybody factorsIt was recently shown that, in a binary coalescence, the greybody factor of the remnant black hole modulates the post-merger ringdown signal. In this work, we demonstrate that a simple four-parameter…Romeo Felice Rosato, Sophia Yi, Emanuele Berti et al.·May 13, 2026SaveLearn
Excitation factors for horizonless compact objects: long-lived modes, echoes, and greybody factorsWe present an analytical and numerical investigation of the quasinormal excitation factors of ultracompact horizonless objects. These systems possess long lived quasinormal modes with extremely small…Romeo Felice Rosato, Shauvik Biswas, Sumanta Chakraborty et al.·May 13, 2026SaveLearn
Scalar fields around black hole binaries in LIGO-Virgo-KAGRALight scalar particles arise naturally in many extensions of the Standard Model and are compelling dark-matter candidates. Gravitational interactions near black holes can trigger the growth of dense…Soumen Roy, Rodrigo Vicente, Josu C. Aurrekoetxea et al.·May 13, 2026SaveLearn
Black hole mergers beyond general relativity: a self-force approachGravitational waves from binary black hole mergers provide a glimpse of gravitational dynamics in its most extreme observable regime, potentially enabling precision tests of general relativity (GR)…Ayush Roy, Lorenzo Küchler, Adam Pound et al.·May 13, 2026SaveLearn
Towards Stochastic Inflation in Higher-Curvature GravityWe study stochastic inflation in the presence of higher-curvature terms non-minimally coupled to the inflaton. Focusing on quadratic curvature invariants, we single out the Gauss-Bonnet term which is…Yermek Aldabergenov, Ding Ding, Wei Lin et al.·May 13, 2026SaveLearn
On the universality of late-time ringdown tailThe late time response of vacuum black holes in General Relativity is notoriously governed by power law tails arising from the wave scattering off the curved spacetime geometry far from the black…Romeo Felice Rosato, Paolo Pani·May 13, 2026SaveLearn
First look at continuous spin gravity: Time delay signaturesWe consider the possibility that gravity is mediated by "continuous spin" particles, i.e.~ massless particles whose invariant spin scale ρg is non-zero. In this case, the primary…Shayarneel Kundu, Philip Schuster, Natalia Toro·May 13, 2026SaveLearn
Greybody factors, reflectionless scattering modes, and echoes of ultracompact horizonless objectsMotivated by a recently discovered connection between the greybody factors of black holes and the ringdown signal, we investigate the greybody factors of ultracompact horizonless objects, also…Romeo Felice Rosato, Shauvik Biswas, Sumanta Chakraborty et al.·May 13, 2026SaveLearn
Tests of General Relativity with GW230529: a neutron star merging with a lower mass-gap compact objectOn May 29, 2023, the LIGO Livingston observatory detected the gravitational-wave signal GW230529181500 from the merger of a neutron star with a lower mass-gap compact object. Its long inspiral…Elise M. Sänger, Soumen Roy, Michalis Agathos et al.·May 13, 2026SaveLearn
Nonsingular Black Holes From Charged Dust Collapse: A Concrete Mechanism to Evade Interior Singularities in General RelativityIn this essay we examine the gravitational collapse of a nonrelativistic charged perfect fluid interacting with a dark energy component. Given a simple factor for the energy transfer, we obtain a…Rodrigo Maier·May 13, 2026SaveLearn
New commutation relations for quantum gravityA new set of fundamental commutation relations (CR) for quantum gravity is presented. The basic variables are the eight components of the unimodular part of the spatial dreibein and eight SL(3,R)…Chopin Soo, Hoi-Lai Yu·May 13, 2026SaveLearn
Impact of coalescence signals on the search for continuous gravitational waves with Einstein TelescopeThe current network of gravitational wave detectors has already revealed hundreds of compact binary coalescences (CBCs), including binary neutron stars, binary black holes, and black hole-neutron…Elena Codazzo, Lorenzo Mirasola, Matteo Di Giovanni et al.·May 12, 2026SaveLearn
Chaos and epoch structure in the deformed Mixmaster universeWe study the dynamics of the Bianchi~IX (Mixmaster) universe under classical polymerization and generalized uncertainty principle (GUP) deformation of the Poisson brackets. Starting from the Misner…Babak Vakili·May 12, 2026SaveLearn
Quasinormal Spectra of Fields of Various Spin in Asymptotically de Sitter Black Holes within Generalized Proca TheoryWe study massless scalar, electromagnetic, and Dirac perturbations of asymptotically de Sitter black holes in generalized Proca theory. These geometries are especially interesting because the Proca…Milena Skvortsova·May 12, 2026SaveLearn
Causality Violating Solutions in Curvature-Squared GravityIn this paper, we consider some causality violating solutions in the curvature-squared gravity in order to examine whether closed timelike curves (CTCs) are allowed in these models. These aspects are…J. C. R. de Souza, A. F. Santos, R. Bufalo·May 12, 2026SaveLearn
The choice of variables in cosmological dynamical systemsDynamical systems techniques are a powerful tool to analyse systems of ordinary differential equations, written in an appropriate form. For a given theory of gravity, the cosmological field equations…Christian G. Boehmer, Antonio d'Alfonso del Sordo·May 12, 2026SaveLearn
A cosmology-to-ringdown EFT consistency map for scalar-tensor gravityWe construct an effective-field-theory bridge from late-time scalar-tensor cosmology to black-hole ringdown observables. Starting from a cosmology-conditioned EFT posterior, we lift Jordan-frame FLRW…Mushtaq Ahmad, M. Farasat Shamir·May 12, 2026SaveLearn
GW240925 and GW250207: Astrophysical Calibration of Gravitational-wave DetectorsGW240925 and GW250207 are two loud gravitational-wave signals from binary black hole coalescences observed with network signal-to-noise ratios 32 and 69, respectively, by the LIGO…The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration et al.·May 12, 2026SaveLearn
Cosmology of f(Q,Lm) gravity with Holographic Ricci Dark Energy: Early-Time Inflation and Late-Time Acceleration and RGUP Corrected ObservablesThis study investigates a cosmological scenario within the f(Q,Lm) gravity framework to explore whether one geometric model can simultaneously describe the early and late-time accelerated epochs.…Khandro K Chokyi, Abdel Nasser Tawfik, Surajit Chattopadhyay·May 12, 2026SaveLearn
Stability and quasi-normal ringing in analogue black-white holes in SNAIL-based traveling-wave parametric amplifiersThe circuit dynamics constructed by traveling-wave parametric amplifiers (TWPA), using superconducting nonlinear asymmetric elements (SNAILs), are known to be approximately described by the…Daisuke Yamauchi, Haruna Katayama, Norihiro Tanahashi·May 12, 2026SaveLearn
Bardeen spacetime as quantum corrected black hole: Grey-body factors and quasinormal modes of gravitational perturbationsWe study axial gravitational perturbations of the asymptotically flat Bardeen spacetime interpreted as a string-T-duality-inspired quantum-corrected Schwarzschild black hole. Starting from the…Bekir Can Lütfüoğlu, Javlon Rayimbaev, Sardor Murodov et al.·May 12, 2026SaveLearn