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A key incentive of quantum gravity is the removal of spacetime singularities plaguing the classical theory. We compute the non-perturbative momentum-dependence of a specific structure function within the gravitational asymptotic safety…

High Energy Physics - Theory · Physics 2019-09-11 Lando Bosma , Benjamin Knorr , Frank Saueressig

We consider a class of spherically symmetric spacetime to obtain some interesting solutions in F(R) gravity without matter field (pure gravity). We investigate the geometry of the solutions and find that there is an essential singularity at…

General Relativity and Quantum Cosmology · Physics 2014-03-03 S. H. Hendi , B. Eslam Panah , C. Corda

We explore the fate of the curvature singularity of Schwarzschild (deSitter) black holes in asymptotically safe quantum gravity. Specifically, we upgrade the classical spacetime by including the running of the Newton coupling and…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Ademola Adeifeoba , Astrid Eichhorn , Alessia Platania

In this work a class of interior solution for Einstein field equations corresponding to a spherically symmetric anisotropic fluid sphere has been obtained under the assumption that the cosmological constant is spatially variable. The…

General Relativity and Quantum Cosmology · Physics 2011-03-07 R. N. Tiwari , Saibal Ray

We study renormalization group equations of quantum gravity in four dimensions. We find an ultraviolet fixed point in accordance with the asymptotic safety conjecture, and infrared fixed points corresponding to general relativity with…

High Energy Physics - Theory · Physics 2012-05-22 Daniel Litim , Alejandro Satz

We consider a Bianchi type III axisymmetric geometry in the presence of an electromagnetic field. A first result at the classical level is that the symmetry of the geometry need not be applied on the electromagnetic tensor $F_{\mu\nu}$; the…

General Relativity and Quantum Cosmology · Physics 2018-04-04 A. Karagiorgos , T. Pailas , N. Dimakis , Petros A. Terzis , T. Christodoulakis

We present a spherically symmetric and static exact solution of Quantum Einstein Equations. This solution is asymptotically (for large $r$) identical with the black hole solution on the anti--De Sitter background and, for some range of…

General Relativity and Quantum Cosmology · Physics 2010-11-19 J. Kowalski - Glikman

Extensions of Einstein gravity with quadratic curvature terms in the action arise in most effective theories of quantised gravity, including string theory. This article explores the set of static, spherically symmetric and asymptotically…

High Energy Physics - Theory · Physics 2015-12-22 H. Lü , A. Perkins , C. N. Pope , K. S. Stelle

We investigate the renormalization group flow of a gravity--matter system in which a scalar field is minimally coupled to Einstein gravity and its kinetic term is given by a scale-dependent form factor $f_\Lambda(-\Box)$. Employing the…

High Energy Physics - Theory · Physics 2026-05-13 Alfio M. Bonanno , Diego Buccio , Emiliano M. Glaviano , Frank Saueressig

We present a covariant model of a spherically symmetric black hole with corrections motivated by loop quantum gravity. The effective modifications, parametrized by a positive constant $\lambda$, are implemented through a canonical…

General Relativity and Quantum Cosmology · Physics 2022-10-07 Asier Alonso-Bardaji , David Brizuela , Raül Vera

The purpose of this work is to investigate spatially homogeneous and flat cosmological solutions of the Einstein equations coupled to a non-variational ``near-minimal'' scalar field. This coupling model represents a minimal departure from…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Joshua Ritchie

The gravitational asymptotic safety program strives for a consistent and predictive quantum theory of gravity based on a non-trivial ultraviolet fixed point of the renormalization group (RG) flow. We investigate this scenario by employing a…

High Energy Physics - Theory · Physics 2011-07-28 Elisa Manrique , Stefan Rechenberger , Frank Saueressig

We present the most general and exact solution of Einstein's gravity sourced by an anisotropic fluid describing the cosmological embedding (CE) of a static and spherically-symmetric object, including black holes (BHs) or exotic compact…

General Relativity and Quantum Cosmology · Physics 2026-03-27 Mariano Cadoni , Leonardo de Lima , Mirko Pitzalis , Davi C. Rodrigues , Andrea P. Sanna

A non-singular, static spherically symmetric solution to the nonsymmetric gravitational and electromagnetic theory field equations is derived, which depends on the four parameters m, l^2, Q and s, where m is the mass, Q is the electric…

General Relativity and Quantum Cosmology · Physics 2008-11-26 N. J. Cornish , J. W. Moffat

Black holes are among the most fascinating objects populating our universe. Their characteristic features, encompassing spacetime singularities, event horizons, and black hole thermodynamics, provide a rich testing ground for quantum…

High Energy Physics - Theory · Physics 2016-02-23 Frank Saueressig , Natalia Alkofer , Giulio D'Odorico , Francesca Vidotto

We investigate perturbations of a class of spherically symmetric solutions in massive gravity and bi-gravity. The background equations of motion for the particular class of solutions we are interested in reduce to a set of the Einstein…

General Relativity and Quantum Cosmology · Physics 2015-09-08 Tsutomu Kobayashi , Masaru Siino , Masahide Yamaguchi , Daisuke Yoshida

In recent years it has emerged that the high energy behavior of gravity could be governed by an ultraviolet non-Gaussian fixed point of the (dimensionless) Newton's constant, whose behavior at high energy is thus {\it antiscreened}. This…

High Energy Physics - Theory · Physics 2011-08-17 Alfio Bonanno

Nonperturbative treatments of the UV limit of pure gravity suggest that it admits a stable fixed point with positive Newton's constant and cosmological constant. We prove that this result is stable under the addition of a scalar field with…

High Energy Physics - Theory · Physics 2011-05-05 Roberto Percacci , Daniele Perini

In this contribution, we discuss the asymptotic safety scenario for quantum gravity with a functional renormalisation group approach that disentangles dynamical metric fluctuations from the background metric. We review the state of the art…

High Energy Physics - Theory · Physics 2021-12-03 Jan M. Pawlowski , Manuel Reichert

We review the solution space for the field equations of Einstein's General Relativity for various static, spherically symmetric spacetimes. We consider the vacuum case, represented by the Schwarzschild black hole; the de…

General Relativity and Quantum Cosmology · Physics 2024-10-02 Andronikos Paliathanasis