The Asymptotic Safety Scenario in Quantum Gravity – An Introduction –
نویسنده
چکیده
The asymptotic safety scenario in quantum gravity is reviewed, according to which a renormalizable quantum theory of the gravitational field is feasible which reconciles asymptotically safe couplings with unitarity. All presently known evidence is surveyed: (a) from the 2+ǫ expansion, (b) from the perturbation theory of higher derivative gravity theories and a 'large N' expansion in the number of matter fields, (c) from the 2-Killing vector reduction, and (d) from truncated flow equations for the effective average action. Special emphasis is given to the role of perturbation theory as a guide to 'asymptotic safety'. Further it is argued that as a consequence of the scenario the selfinter-actions appear two-dimensional in the extreme ultraviolet. Two appendices discuss the distinct roles of the ultraviolet renormalization in perturbation theory and in the flow equation formalism. * Membre du CNRS.
منابع مشابه
6 The Asymptotic Safety Scenario in Quantum Gravity – An Introduction –
The asymptotic safety scenario in quantum gravity is reviewed, according to which a renormalizable quantum theory of the gravitational field is feasible which reconciles asymptotically safe couplings with unitarity. All presently known evidence is surveyed: (a) from the 2 + ǫ expansion, (b) from renor-malizable higher derivative gravity theories and a 'large N' expansion in the number of matter...
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