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Related papers: On fixed points of quantum gravity

200 papers

If gravity is asymptotically safe, operators will exhibit anomalous scaling at the ultraviolet fixed point in a way that makes the theory effectively two-dimensional. A number of independent lines of evidence, based on different approaches…

General Relativity and Quantum Cosmology · Physics 2019-04-10 S. Carlip

We explore asymptotic safety of gravity-matter systems, discovering indications for a near-perturbative nature of these systems in the ultraviolet. Our results are based on the dynamical emergence of effective universality at the…

High Energy Physics - Theory · Physics 2019-04-19 Astrid Eichhorn , Stefan Lippoldt , Jan M. Pawlowski , Manuel Reichert , Marc Schiffer

We formulate a renormalizable quantum gravity in $2+\epsilon$ dimensions by generalizing the nonlinear sigma model approach to string theory. We find that the theory possesses the ultraviolet stable fixed point if the central charge of the…

High Energy Physics - Theory · Physics 2009-10-22 Hikaru Kawai , Yoshihisa Kitazawa , Masao Ninomiya

The exact renormalization group equation for pure quantum gravity is used to derive the non-perturbative $\Fbeta$-functions for the dimensionless Newton constant and cosmological constant on the theory space spanned by the Einstein-Hilbert…

High Energy Physics - Theory · Physics 2010-04-06 M. Reuter , F. Saueressig

We highlight how the existence of an ultraviolet completion for interacting Standard-Model type matter puts constraints on the viable microscopic dynamics of asymptotically safe quantum gravity within truncated Renormalization Group flows.…

General Relativity and Quantum Cosmology · Physics 2017-12-01 Astrid Eichhorn , Aaron Held

Unimodular gravity is classically equivalent to standard Einstein gravity, but differs when it comes to the quantum theory: The conformal factor is non-dynamical, and the gauge symmetry consists of transverse diffeomorphisms only.…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Astrid Eichhorn

We consider a discrete model of euclidean quantum gravity in four dimensions based on a summation over random simplicial manifolds. The action used is the Einstein-Hilbert action plus an $R^2$-term. The phase diagram as a function of the…

High Energy Physics - Theory · Physics 2009-10-22 J. Ambjorn , J. Jurkiewicz , C. F. Kristjansen

Realizing a quantum theory for gravity based on Asymptotic Safety hinges on the existence of a non-Gaussian fixed point of the theory's renormalization group flow. In this work, we use the functional renormalization group equation for the…

High Energy Physics - Theory · Physics 2015-09-30 Maximilian Demmel , Frank Saueressig , Omar Zanusso

Considering the Einstein-Hilbert truncation for the running action in (euclidean) quantum gravity, we derive the renormalization group equations for the cosmological and Newton constant. We find that these equations admit only the Gaussian…

High Energy Physics - Theory · Physics 2024-12-19 C. Branchina , V. Branchina , F. Contino , A. Pernace

The methods of the renormalization group and the $\varepsilon$-expansion are applied to quantum gravity revealing the existence of an asymptotically safe fixed point in spacetime dimensions higher than two. To facilitate this, physical…

High Energy Physics - Theory · Physics 2018-01-04 Kevin Falls

Motivated by the conjecture that the cosmological constant problem could be solved by strong quantum effects in the infrared we use the exact flow equation of Quantum Einstein Gravity to determine the renormalization group behavior of a…

High Energy Physics - Theory · Physics 2009-11-07 M. Reuter , F. Saueressig

The quantum Einstein gravity is treated by the functional renormalization group method using the Einstein-Hilbert action. The ultraviolet non-Gaussian fixed point is determined and its corresponding exponent of the correlation length is…

High Energy Physics - Theory · Physics 2015-06-16 S. Nagy , B. Fazekas , L. Juhasz , K. Sailer

We investigate the ultraviolet behaviour of quantum gravity within a functional renormalisation group approach. The present setup includes the full ghost and graviton propagators and, for the first time, the dynamical graviton three-point…

High Energy Physics - Theory · Physics 2016-05-23 Nicolai Christiansen , Benjamin Knorr , Jan Meibohm , Jan M. Pawlowski , Manuel Reichert

We zoom in on the microscopic dynamics for fermions and quantum gravity within the asymptotic-safety paradigm. A key finding of our study is the unavoidable presence of a nonminimal derivative coupling between the curvature and fermion…

High Energy Physics - Theory · Physics 2019-04-19 Astrid Eichhorn , Stefan Lippoldt , Marc Schiffer

Application of the Weinberg's conditions of asymptotic safety to amplitudes and not to couplings of the effective action can help to uniquely define the running in the UV and avoid some of the asymptotic safety program problems. The idea is…

High Energy Physics - Theory · Physics 2021-02-17 Jan H. Kwapisz , Krzysztof A. Meissner

Asymptotic Safety provides a mechanism for constructing a consistent and predictive quantum theory of gravity valid on all length scales. Its key ingredient is a non-Gaussian fixed point of the gravitational renormalization group flow which…

High Energy Physics - Theory · Physics 2017-04-26 Jorn Biemans , Alessia Platania , Frank Saueressig

Motivated by the conjecture that the cosmological constant problem is solved by strong quantum effects in the infrared we use the exact flow equation of Quantum Einstein Gravity to determine the renormalization group behavior of a class of…

High Energy Physics - Theory · Physics 2009-11-10 M. Reuter , F. Saueressig

We construct a novel Wetterich-type functional renormalization group equation for gravity which encodes the gravitational degrees of freedom in terms of gauge-invariant fluctuation fields. Applying a linear-geometric approximation the…

High Energy Physics - Theory · Physics 2015-04-30 Maximilian Demmel , Frank Saueressig , Omar Zanusso

We study the non-perturbative renormalization group flow of higher-derivative gravity employing functional renormalization group techniques. The non-perturbative contributions to the $\beta$-functions shift the known perturbative…

High Energy Physics - Theory · Physics 2009-10-08 Dario Benedetti , Pedro F. Machado , Frank Saueressig

We review aspects of the interplay of asymptotically safe gravity with matter, focusing on the potential predictive power of the quantum scale-symmetry underlying the asymptotically safe fixed point. We explain how an asymptotically safe…

High Energy Physics - Theory · Physics 2019-07-12 Astrid Eichhorn , Aaron Held