409 papers
This paper explores extending Bimetric MOND (BIMOND) to create variable- theories that naturally satisfy local constraints on the constancy of Newton's constant while allowing for a different, enhanced effective gravitational constant () in cosmological settings to potentially explain dark matter effects without new degrees of freedom.
This paper proposes a unified thermodynamic framework where cosmic acceleration emerges from an entropic force driven by a generalized mass-to-horizon scaling relation, and demonstrates through a comprehensive Bayesian analysis of multi-probe observational data that this entropic cosmology is statistically preferred over the standard CDM model.
This paper establishes theoretical mass limits for compact objects in deformed Hořava-Lifshitz gravity, demonstrating that both the uniform density and causal sound speed bounds converge at the extremal black hole horizon () within the Kehagias-Sfetsos vacuum solution.
This paper demonstrates that the chaos bound proposed in MSS can be violated in the spinor field of a Reissner-Nordström black hole by analyzing the orbital motions of both neutral and charged spinning particles, showing that sufficiently large spin magnitudes or specific spin-angular momentum alignments lead to Lyapunov exponents exceeding the surface gravity.
This paper derives a model-independent upper limit on the amplitude of a chiral gravitational wave background produced before the electroweak epoch, which, for high reheating temperatures, provides a significantly more stringent constraint than standard big bang nucleosynthesis bounds at frequencies above the MHz scale.
Motivated by string T-duality, this paper constructs a nonsingular "black bounce" spacetime that interpolates between regular black holes and traversable wormholes, demonstrating its thermodynamic stability, phase transitions, and consistency with Event Horizon Telescope observations while identifying the specific energy conditions violated by the underlying effective fluid.
This paper reviews the analogue gravity description of unidirectional water waves in two-dimensional flows with constant shear, demonstrating that such flows can be effectively modeled by a curved spacetime metric without requiring prior knowledge of general relativity.
This paper presents environmental measurements at the Sedrun Access Shaft in Switzerland, demonstrating that its low ground motion and electromagnetic background levels make it a viable site for an 800-meter atom interferometer designed to detect ultralight dark matter and gravitational waves.
This paper introduces SEOB-TML, an enhanced effective-one-body framework for extreme-mass-ratio binary black holes that improves waveform accuracy in the test-mass limit by incorporating a quadrupole-factorized flux prescription, a phenomenological merger-ringdown ansatz, and explicit mode-mixing modeling, thereby significantly reducing dephasing and residuals compared to state-of-the-art models.
This paper presents a systematic study of the continuum spectrum of spherical multi-frequency Proca stars, demonstrating that they interpolate between discrete stationary states and that a subset of these configurations are linearly stable, with potential implications for determining particle spin in ultralight dark matter models.
This paper refutes claims that fourth-order scalar fields can solve the cosmological constant problem or generate primordial density perturbations without inflation, arguing instead that such theories inherently suffer from fatal pathologies including ghost-induced instabilities, unitarity violations, and the generation of a confining fifth force.
This paper proposes a unified framework demonstrating that the structural difference in decoherence—specifically, the preservation of coherence within the lowest phonon-number manifold by a quantized graviton bath versus its inevitable destruction by a classical stochastic gravitational field—provides an operational criterion for distinguishing the quantum or classical nature of gravitational waves using mesoscopic optomechanical systems.
This paper introduces and validates new explicit fourth-order Multistep Runge-Kutta (MSRK) methods that accelerate Numerical Relativity simulations by reusing data from previous time steps to reduce intermediate stage evaluations, while providing a procedure to tune coefficients for maximizing stable time step sizes.
This paper introduces a novel search framework for precessing binary black hole systems in LIGO-Virgo-KAGRA data that utilizes mode-by-mode filtering, machine learning-based template reduction, and marginalization over harmonic signal-to-noise ratios to overcome the computational and statistical challenges of spin precession, ultimately increasing the sensitive search volume by approximately 10%.
This paper introduces "Black Hole Vision," an open-source iOS application that utilizes Schwarzschild and Kerr black hole lensing equations to synthesize real-time, gravitationally lensed views of a user's surroundings, thereby visualizing the horizon-scale features expected from the proposed Black Hole Explorer (BHEX) mission.
This paper derives exact one-loop QED effective actions for scalar and spinor fields in global (anti-)de Sitter spacetime under a uniform electric field by utilizing the in-out formalism and Bogoliubov coefficients, revealing a strong interplay between electric fields and spacetime curvature while recovering known limits in pure (A)dS and Minkowski spaces.
This paper introduces a Multi-Segment Consistency Test (MSCT) that generalizes existing general relativity tests by ensuring physical consistency across independent signal segments, which, when applied to the GW250114 event, yields a $4.61\sigma$ confirmation of Hawking's area increase law with unprecedented precision.
This paper demonstrates that even at very small centripetal accelerations, circular motion intrinsically and anisotropically modifies the Lamb shift of atoms, with the effect's magnitude and sign depending critically on the atomic polarization direction and potentially rivaling the inertial Lamb shift when angular velocity exceeds the transition frequency.
This paper introduces \emph{tdanalysis}, a fully time-domain framework for gravitational-wave inference that leverages structured linear algebra and GPU acceleration to overcome the limitations of traditional frequency-domain methods while efficiently handling data gaps and sharp boundaries.
This paper investigates the Cuscuton-Galileon model through Lie point symmetry and Killing analysis, revealing that the symmetry constraints eliminate the original Cuscuton term and restrict the potential to an exponential form, leading to a two-degree-of-freedom system that exhibits damped oscillatory cosmological behavior when a specific coefficient vanishes.