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Related papers: Zooming in on fermions and quantum gravity

200 papers

We study the quantum properties of the three-dimensional higher derivative gravity. In particular we calculate the running of the gravitational and cosmological constants. The flow of these couplings shows that there exist both Gaussian and…

High Energy Physics - Theory · Physics 2015-06-05 Nobuyoshi Ohta

We present the first numerical study of the ultraviolet dynamics of non-asymptotically free gauge-fermion theories at large number of matter fields. As testbed theories we consider non-abelian SU(2) gauge theories with 24 and 48 Dirac…

High Energy Physics - Lattice · Physics 2020-04-15 Viljami Leino , Tobias Rindlisbacher , Kari Rummukainen , Francesco Sannino , Kimmo Tuominen

We study quantum gravity in more than four dimensions with renormalisation group methods. We find a non-trivial ultraviolet fixed point in the Einstein-Hilbert action. The fixed point connects with the perturbative infrared domain through…

High Energy Physics - Theory · Physics 2008-11-26 Peter Fischer , Daniel F. Litim

We study the impact of quantum gravity, formulated as a quantum field theory of the metric, on chiral symmetry in a fermionic matter sector. We specifically address the question as to whether metric fluctuations can induce chiral symmetry…

High Energy Physics - Theory · Physics 2015-05-28 Astrid Eichhorn , Holger Gies

The availability of scaling solutions in renormalisation group improved versions of cosmology are investigated in the high-energy limit. We adopt $f(R)$-type models of quantum gravity which display an interacting ultraviolet fixed point at…

General Relativity and Quantum Cosmology · Physics 2018-05-16 Kevin Falls , Daniel F. Litim , Kostas Nikolakopoulos , Christoph Rahmede

In the asymptotic safety paradigm, a quantum field theory reaches a regime with quantum scale invariance in the ultraviolet, which is described by an interacting fixed point of the Renormalization Group. Compelling hints for the viability…

General Relativity and Quantum Cosmology · Physics 2018-08-01 Astrid Eichhorn

We study the short distance behaviour of euclidean quantum gravity in the light of Weinberg's asymptotic safety scenario. Implications of a non-trivial ultraviolet fixed point are reviewed. Based on an optimised renormalisation group, we…

High Energy Physics - Theory · Physics 2009-11-11 Daniel F. Litim

We study the asymptotic safety conjecture for quantum gravity in the presence of matter fields. A general line of reasoning is put forward explaining why gravitons dominate the high-energy behaviour, largely independently of the matter…

High Energy Physics - Theory · Physics 2018-06-15 Nicolai Christiansen , Daniel F. Litim , Jan M. Pawlowski , Manuel Reichert

We review and extend in several directions recent results on the asymptotic safety approach to quantum gravity. The central issue in this approach is the search of a Fixed Point having suitable properties, and the tool that is used is a…

High Energy Physics - Theory · Physics 2013-08-28 Alessandro Codello , Roberto Percacci , Christoph Rahmede

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 investigate the compatibility of minimally coupled scalar, fermion and gauge fields with asymptotically safe quantum gravity, using nonperturbative functional Renormalization Group methods. We study d=4,5 and 6 dimensions and within…

High Energy Physics - Theory · Physics 2024-02-27 Pietro Donà , Astrid Eichhorn , Roberto Percacci

We study quantum gravity in more than four dimensions by means of an exact functional flow. A non-trivial ultraviolet fixed point is found in the Einstein-Hilbert theory. It is shown that our results for the fixed point and universal…

High Energy Physics - Theory · Physics 2009-11-11 Peter Fischer , Daniel F. Litim

We consider the asymptotic-safety scenario for quantum gravity which constructs a non-perturbatively renormalisable quantum gravity theory with the help of the functional renormalisation group. We verify the existence of a non-Gaussian…

High Energy Physics - Theory · Physics 2009-11-10 Astrid Eichhorn , Holger Gies , Michael M. Scherer

Within the functional renormalization group approach we study the effective QFT of Einstein gravity and one self-interacting scalar coupled to N_f Dirac fermions. We include in our analysis the matter anomalous dimensions induced by all the…

High Energy Physics - Theory · Physics 2010-12-28 G. P. Vacca , O. Zanusso

In this work we investigate the ultraviolet behavior of Euclidean four-derivative quantum gravity beyond perturbation theory. In addition to a perturbative fixed point, we find an ultraviolet fixed point that is non-trivial in all couplings…

High Energy Physics - Theory · Physics 2016-12-20 Nicolai Christiansen

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

I review the field-theoretic renomalization group approach to quantum gravity, built around the existence of a non-trivial ultraviolet fixed point in four dimensions. I discuss the implications of such a fixed point, found in three largely…

High Energy Physics - Theory · Physics 2010-02-04 Herbert W. Hamber

I review the lattice approach to quantum gravity, and how it relates to the non-trivial ultraviolet fixed point scenario of the continuum theory. After a brief introduction covering the general problem of ultraviolet divergences in gravity…

General Relativity and Quantum Cosmology · Physics 2009-04-17 Herbert W. Hamber

We investigate the phase diagram of quantum gravity with a vertex expansion about constantly-curved backgrounds. The graviton two- and three-point function are evaluated with a spectral sum on a sphere. We obtain, for the first time,…

High Energy Physics - Theory · Physics 2019-11-28 Nicolai Christiansen , Kevin Falls , Jan M. Pawlowski , Manuel Reichert

We present and discuss well known conditions for ultraviolet finiteness and asymptotic safety. The requirements for complete absence of ultraviolet divergences in quantum field theories and existence of a non-trivial fixed point for…

High Energy Physics - Theory · Physics 2022-04-22 Leslaw Rachwal