3151 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 develops linear perturbation theory for general Bianchi spacetimes in the Newtonian gauge, deriving equations for scalar and tensor modes—including a Bianchi-specific Mukhanov-Sasaki equation and modified Friedmann equations—to facilitate the comparison of anisotropic cosmological models with observational data like the CMB.
This paper demonstrates that the apparent observational preference for dark energy models violating the null energy condition at high redshift is a misleading artifact of the standard - parameterization, as simple quintessence models satisfying the null energy condition for all redshifts predict the same observational signature.
This paper demonstrates that while potential-driven early dark energy scenarios can be realized in gravity to alleviate the Hubble tension, they are generally excluded by stringent equivalence principle constraints, implying that nonperturbative effects or nontrivial mechanisms are necessary to reconcile such models with local gravity tests.
This paper presents a construction of a four-dimensional spacetime from a three-dimensional contact manifold with a degenerate metric, yielding a solution to the Einstein equation for null dust and cosmic strings that is either conformally flat or of Petrov type D depending on the presence of cosmic strings.
This paper proposes an asymmetrical two-brane model where the Higgs vacuum expectation value varies between branes, resulting in superheavy fermions on a second, observer-free brane that could constitute a component of dark matter and generate ultra-high-energy particles through inter-brane photon interactions.
This paper computes primordial density perturbation correlation functions arising from the coupling of inflation to a gapless, strongly coupled "unparticle" sector, deriving explicit bispectra and trispectra shapes via Mellin-Barnes integration and weight-shifting operators to demonstrate that full shape analysis, rather than just squeezed limits, is required to distinguish unparticles from light particles.
This paper investigates how non-metricity within bumblebee gravity modifies neutrino behavior around a specific black hole configuration, analyzing its effects on energy deposition from annihilation, oscillation phases, flavor transition probabilities via lensing, and numerical oscillation outcomes for both mass orderings.
This paper establishes that the universal time evolution of holographic complexity—characterized by a slope-ramp-plateau structure with linear growth and late-time saturation—is fundamentally driven by random matrix universality and a specific pole structure in the generating functions, which are proven to be necessary and sufficient conditions for these behaviors via the residue theorem.
This paper extends the dynamical systems toolkit for multiscalar dark energy by introducing new variables that disentangle kinetic couplings, enabling a systematic stability analysis that reveals genuinely non-geodesic attractors in exponential models while correcting previous misconceptions about non-geodesic fixed points in shift-symmetric scenarios.
This paper investigates the viability of teleparallel gravity models by deriving and analyzing the equations of motion for gauge-invariant cosmological perturbations to assess their stability and physical implications beyond background-level studies.