title: Non-Perturbative Aspects of Quantum  Field Theory:  From the Quark-Gluon Plasma to  Quantum Gravity
creator: Christiansen, Nicolai
subject: ddc-500
subject: 500 Natural sciences and mathematics
subject: ddc-530
subject: 530 Physics
description: In this dissertation we investigate several aspects of non-perturbative quantum field theory.  Two main parts of the thesis are concerned with non-perturbative renormalization  of quantum gravity within the asymptotic safety scenario. This framework is based on a  non-Gaussian ultraviolet fixed point and provides a well-defined theory of quantized gravity.  We employ functional renormalization group (FRG) techniques that allow for the study of  quantum fields even in strongly coupled regimes. We construct a setup for the computation  of graviton correlation functions and analyze the ultraviolet completion of quantum gravity  in terms of the properties of the two- and three point function of the graviton. Moreover, the  coupling of gravity to Yang–Mills theories is discussed. In particular, we study the effects  of graviton induced interactions on asymptotic freedom on the one hand, and the role of  gluonic fluctuations in the gravity sector on the other hand.  The last subject of this thesis is the physics of the quark-gluon plasma. We set-up a general  non-perturbative strategy for the computation of transport coefficients in non-Abelian gauge  theories. We determine the viscosity over entropy ratio in SU(3) Yang–Mills theory as a  function of temperature and estimate its behavior in full quantum chromodynamics (QCD).
date: 2015
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/19254/1/Dissertation_Christiansen.pdf
identifier: DOI:10.11588/heidok.00019254
identifier: urn:nbn:de:bsz:16-heidok-192548
identifier:   Christiansen, Nicolai  (2015) Non-Perturbative Aspects of Quantum Field Theory: From the Quark-Gluon Plasma to Quantum Gravity.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/19254/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng