3278 papers
Quantum gravity represents the frontier where the very large meets the very small, attempting to unify Einstein's theory of gravity with the strange rules of quantum mechanics. This field explores the fundamental fabric of spacetime, seeking to understand how the universe behaves at its most extreme scales, from the heart of black holes to the moment of the Big Bang. Because these concepts often involve complex mathematics, they can feel distant to non-specialists, yet they hold the key to a complete picture of physical reality.
At Gist.Science, we bridge this gap by processing every new preprint in this category directly from arXiv. Our team provides both plain-language explanations and detailed technical summaries for each paper, ensuring that groundbreaking research is accessible to everyone, from curious students to seasoned researchers. Below are the latest papers in quantum gravity, offering fresh insights into the nature of our cosmos.
This paper identifies and clarifies two compensating sign errors in the 1973 Bardeen-Carter-Hawking paper on black hole mechanics, demonstrating that while the definitions of total particle number and entropy were missing minus signs and the mass formula equations had incorrect signs, these errors canceled each other out, leaving all original conclusions valid.
This paper investigates the optical and radiative signatures of an accretion disk around a Schwarzschild black hole immersed in a uniform magnetic field within the Schwarzschild-Bertotti-Robinson spacetime, revealing that increasing magnetic field strength expands key characteristic radii, contracts the observed direct image, and dramatically reduces radiative efficiency by up to 91%.
This paper derives an equidistant, discrete spectrum for the black hole horizon area operator in theories with non-minimally coupled scalar fields using the weak isolated horizon formalism, demonstrating that horizon geometry is inherently discrete independent of specific quantum gravity theories and yielding black hole entropy consistent with the Bekenstein-Mukhanov proposal.
This paper introduces a new non-parametric method to constrain the ratio between gravitational-wave and electromagnetic-wave luminosity distances, which, when applied to GWTC-3 binary black hole merger data, yields results consistent with General Relativity and previous parametric analyses.
Motivated by a one-cycle cosmological scenario where the Big Bang emerges from a Euclidean regime, this paper proposes that black holes could serve as entry portals to such a realm, requiring them to contain de Sitter cores and a spacelike shell of non-inflationary matter to ensure metric regularity.
By developing a gravitational-wave waveform model that incorporates a slowly varying gravitational constant and applying it to a joint multi-messenger analysis of the binary neutron star merger GW170817, this study finds no evidence for temporal variation in and establishes the most stringent constraints to date on its fractional time derivative, thereby validating the strong equivalence principle in the relativistic regime.
This paper derives exact quasinormal modes for massive scalar, fermionic, and vector perturbations around a rotating BTZ-like black hole in Einstein-bumblebee gravity, revealing that the Lorentz symmetry breaking parameter slows field decay by affecting only the imaginary parts of the frequencies while preserving the standard BTZ real parts and confirming the validity of the AdS/CFT correspondence through universal conformal weights.
This paper investigates implementations of quantum Bell causality in causal set quantum gravity, demonstrating that natural operator orderings force the transition algebra to be commutative, while a size-dependent ordering yields new constraints but still faces significant hurdles in constructing non-trivial non-commutative representations.
This perspectives article explores the synergies between particle physics and gravitational wave astronomy, highlighting how next-generation gravitational wave measurements can provide complementary insights into dense matter, dark matter, early Universe phase transitions, and cosmological evolution that extend beyond the reach of current and future particle colliders.
This paper investigates a density-driven interacting dark energy model within a conformally coupled scalar-tensor framework, finding that current cosmological data show no significant preference over CDM and constrain the model to a hierarchical regime where the scalar field remains heavier than the Hubble scale, with the choice of a fixed versus variable activation index significantly affecting the posterior parameter constraints.