2488 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 demonstrates that pulsar timing array observations of scalar-induced gravitational waves impose stringent constraints on the abundance of primordial black holes, particularly for stellar-mass objects, though these limits are significantly relaxed by positive non-Gaussianities or alternative formation theories like the peaks formalism.
This paper establishes the well-posedness of the initial boundary value problem for the vacuum Einstein equations under conformal-mean curvature boundary conditions by proving the dense range of the linearized solution space and a Holmgren-type uniqueness theorem, provided an arbitrary corner angle term is included at the intersection of the Cauchy surface and the timelike boundary.
This paper introduces a Lorentzian Gromov-Hausdorff convergence framework based on causal diamonds and the time separation function, establishing pre-compactness theorems for globally hyperbolic spacetimes and demonstrating the stability of timelike sectional curvature bounds along with connections to causal set theory.
This paper proposes that quasi-periodic eruptions (QPEs) like RX J1301.9+2747 can be explained by extreme-mass-ratio inspirals interacting with accretion disks, predicting distinct gravitational wave signatures with frequency shifts and high-frequency tails that future space-based detectors like LISA could use to distinguish these events from vacuum systems and probe the origins of QPEs.
This paper investigates the late-time growth of holographic complexity in various black hole spacetimes using both volume and action prescriptions, revealing that while the action proposal yields a universal thermodynamic scaling, the complexity growth rate exhibits non-trivial, process-dependent variations under physical perturbations like the Penrose process and particle accretion that highlight the limitations of equilibrium-based treatments.
This paper proposes that discrepancies between electromagnetic and gravitational mass measurements of white dwarfs can be explained by the presence of a gravitationally coupled, electromagnetically invisible bosonic scalar field, which constitutes 5–15% of the stellar mass and allows for new constraints on ultralight dark matter particles.
This paper demonstrates that while late-time dynamical dark energy models can mildly improve cosmological fits, imposing early-time non-phantom scaling behavior is strongly disfavored by current observational data, as it requires steep potentials that fail to alleviate the Hubble tension and are penalized by Bayesian model selection.
This paper proposes a systematic top-down approach using cavity-based effective descriptions to derive observable gravitational wave signatures, particularly phase shifts, from modified black hole dynamics motivated by quantum consistency or new physics.
This paper refutes the claim that the star "Phoebe" in the Large Magellanic Cloud was a microlensing event caused by a primordial black hole, demonstrating instead that its observed brightenings are characteristic of an ordinary variable star, thereby resolving tensions with previous constraints on dark matter composition.
This paper proposes a variational framework that treats reheating as a constrained optimization problem to identify equation-of-state histories that extremize specific cosmological observables, demonstrating that different signals like gravitational waves and primordial black holes select distinct regions of post-inflationary expansion histories without relying on microscopic models.