gr-qc

Comparing Minimal and Non-Minimal Quintessence Models to 2025 DESI Data

Could a so far ignored symmetry of the classical laws of gravity explain the cosmological puzzles?

This paper proposes that classical gravity possesses a previously overlooked Weyl symmetry, which, by allowing mass and energy density to transform conformally, offers a unified explanation for dark matter and dark energy while potentially resolving spacetime singularities.

Inferring neutron-star Love-Q relations from gravitational waves in the hierarchical Bayesian framework

This study employs a hierarchical Bayesian framework to analyze simulated gravitational wave data from binary neutron star mergers, demonstrating that a linear logarithmic relation between tidal deformability and quadrupole moment is sufficient for future measurements and can constrain the characteristic length of dynamical Chern-Simons modified gravity to 10 km or less.

Study of Neutron Star Properties under the Two-Flavor Quark NJL Model

This study demonstrates that constructing a hadron-quark hybrid equation of state using a DDME2 hadronic model and a two-flavor NJL quark model with a smooth quintic interpolation reveals that an early onset of quark degrees of freedom near nuclear saturation density is necessary to simultaneously satisfy the mass constraints of PSR J0740+6620 and the radius/tidal deformability limits from NICER observations.

Various metric forms of all type D black holes and their application

This paper summarizes the complete class of exact type D Einstein-Maxwell-$\Lambda$ solutions, presenting their various metric representations and demonstrating their utility in analyzing physical properties such as singularities, horizons, and thermodynamics, while proving that gravitational radiation is emitted if and only if the black holes accelerate.

Limits on the Statistical Description of Charged de Sitter Black Holes

This paper resolves thermodynamic ambiguities in four-dimensional charged de Sitter black holes by adopting a Bousso-Hawking normalization relative to a freely-falling observer, revealing that while the near-extremal Nariai limit avoids a breakdown of the semi-classical description due to finite heat capacity, fundamental statistical limitations persist in the cold and ultracold regimes where the heat capacity vanishes.

Born-Infeld Electrogravity and Dyonic Black Holes

This paper derives the field equations of Born-Infeld electrogravity using Palatini's formalism, revealing that the theory reduces to Einstein's gravity coupled to either standard or anomalous Born-Infeld electrodynamics, and demonstrates that spherically symmetric dyonic black holes in this framework admit a fundamental extremal state in the small-charge limit determined solely by fundamental constants.

Effects of New Forces on Scalar Dark Matter Solitons

This paper numerically investigates how introducing a new, light-mediator force between light bosonic dark matter particles alters the density-radius relationship of gravitationally bound scalar solitons (boson stars), finding that while such a force can modestly improve fits to observed galactic core data, the effect remains limited even at gravitational-strength couplings.

Gravitational Waves from the Big Bang

This dissertation investigates gravitational waves from cosmic inflation to explore the primordial universe and specifically explains how the signal detected by the NANOGrav observatory could have originated from the early cosmos.

Comparing next-generation detector configurations for high-redshift gravitational wave sources with neural posterior estimation

This study utilizes neural posterior estimation to demonstrate that a network of two misaligned L-shaped Einstein Telescope detectors, potentially augmented by Cosmic Explorer, offers improved sky and volume localization for high-redshift massive binary black hole mergers compared to a triangular configuration, despite exhibiting multimodal distance posteriors.