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Related papers: Composite Operators in Asymptotic Safety

200 papers

The gravitational asymptotic safety program envisions the high-energy completion of gravity through an interacting renormalization group fixed point, the Reuter fixed point. The predictive power of the construction is encoded in the…

High Energy Physics - Theory · Physics 2024-02-05 Maximilian Becker , Alexander Kurov , Frank Saueressig

This paper is one of a series of papers on coherent spaces and their applications, defined in the recent book 'Coherent Quantum Mechanics' by the first author. The paper studies coherent quantization -- the way operators in the quantum…

Mathematical Physics · Physics 2022-02-08 Arnold Neumaier , Arash Ghaani Farashahi

Form factors constitute the key building block when organising the gravitational dynamics in terms of a curvature expansion. They generalise the concept of momentum-dependent couplings to curved spacetime. Moreover, they may capture…

High Energy Physics - Theory · Physics 2021-11-25 Benjamin Knorr , Chris Ripken , Frank Saueressig

The gravitational effective average action is studied in a bimetric truncation with a nontrivial background field dependence, and its renormalization group flow due to a scalar multiplet coupled to gravity is derived. Neglecting the metric…

High Energy Physics - Theory · Physics 2011-03-04 Elisa Manrique , Martin Reuter , Frank Saueressig

The SMEFT provides a general framework to search for new physics beyond the current reach of direct detection. One such form of new physics is quantum gravity. Based on dimensional analysis, one would expect the prediction that the…

High Energy Physics - Phenomenology · Physics 2024-07-18 Lydia Brenner , Abhishek Chikkaballi , Astrid Eichhorn , Shouryya Ray

We study the non-perturbative renormalisation of quantum gravity in four dimensions. Taking care to disentangle physical degrees of freedom, we observe the topological nature of conformal fluctuations arising from the functional measure.…

High Energy Physics - Theory · Physics 2016-04-27 Kevin Falls

The asymptotic safety conjecture is examined for quantum gravity in four dimensions. Using the renormalisation group, we find evidence for an interacting UV fixed point for polynomial actions up to the 34th power in the Ricci scalar. The…

High Energy Physics - Theory · Physics 2016-05-18 Kevin Falls , Daniel F. Litim , Konstantinos Nikolakopoulos , Christoph Rahmede

We demonstrate that it is possible to construct operators that stabilize the constraint-satisfying subspaces of computational problems in their Ising representations. We provide an explicit recipe to construct unitaries and associated…

We use the functional renormalization group equation for the effective average action to study the fixed point structure of gravity-fermion systems on a curved background spacetime. We approximate the effective average action by the…

High Energy Physics - Theory · Physics 2020-10-06 Jesse Daas , Wouter Oosters , Frank Saueressig , Jian Wang

Unimodular gravity is classically equivalent to General Relativity. This equivalence extends to actions which are functions of the curvature scalar. At the quantum level, the dynamics could differ. Most importantly, the cosmological…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Astrid Eichhorn

Utilizing the previously established general formalism for quantum symmetry reduction in the framework of loop quantum gravity the spectrum of the area operator acting on spherically symmetric states in 4 dimensional pure gravity is…

High Energy Physics - Theory · Physics 2009-10-31 M. Bojowald , H. A. Kastrup

Motivated by Weinberg's asymptotic safety scenario, we investigate the gravitational renormalization group flow in the Einstein-Hilbert truncation supplemented by the wave-function renormalization of the ghost fields. The latter induces…

High Energy Physics - Theory · Physics 2014-11-20 Kai Groh , Frank Saueressig

Loop Quantum Gravity (LQG) is an attempt to describe the quantum gravity regime. Introducing a non-zero cosmological constant $\Lambda$ in this context has been a withstanding problem. Other approaches, such as Chern-Simons gravity, suggest…

General Relativity and Quantum Cosmology · Physics 2013-07-24 Maite Dupuis , Florian Girelli

In the search for a quantum theory of gravity it is crucial to find experimental access to quantum gravitational effects. Since these are expected to be very small at observationally accessible scales it is advantageous to consider…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Babette Döbrich , Astrid Eichhorn

The formulation of an exact functional renormalization group equation for Quantum Einstein Gravity necessitates that the underlying effective average action depends on two metrics, a dynamical metric giving the vacuum expectation value of…

High Energy Physics - Theory · Physics 2011-03-04 Elisa Manrique , Martin Reuter , Frank Saueressig

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

Working within the framework of Loop Quantum Gravity (LQG), we construct a set of three operators suitable for identifying coordinate-like quantities on a spin-network configuration. In doing so, we rely on known properties of operators for…

High Energy Physics - Theory · Physics 2018-07-19 Suddhasattwa Brahma , Antonino Marcianò , Michele Ronco

The effective potential of the conformal factor in the effective average action approach to Quantum Einstein Gravity is discussed. It is shown, without invoking any truncation or other approximations, that if the theory has has a…

High Energy Physics - Theory · Physics 2011-08-17 Jan-Eric Daum , Martin Reuter

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 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