TY - BOOK

T1 - Quantum Gravity in Two Dimensions

AU - Ipsen, Asger Cronberg

PY - 2015

Y1 - 2015

N2 - The topic of this thesis is quantum gravity in 1 + 1 dimensions. We will focuson two formalisms, namely Causal Dynamical Triangulations (CDT) and Dy-namical Triangulations (DT). Both theories regularize the gravity path integralas a sum over triangulations. The difference lies in the class of triangulationsconsidered. While the CDT triangulations have a natural Lorentzian structure,in DT the triangulations are Euclidean.The thesis is built up around three papers, reproduced as Chapter 3, 4 and 6.The outline is as follows: The rst two chapters provides background materialon path integral quantization and the CDT formalism. In Chapter 3 we considera generalization of CDT (introduced in Ref. [43]) and show that the continuumlimit is the same as for plain CDT. This provides evidence for the robustness ofthe CDT universality class. Chapter 4 provides an analysis of CDT coupled toYang-Mills theory. In Chapter 5 we review the DT formalism and some basicaspects of Liouville Theory. We put special emphasis on some subtleties of thecontinuum limit. Finally, Chapter 6 contains a discussion on mixing betweengeometrical and matter degrees of freedom, when DT is coupled to non-unitaryCFTs.Most of the material in Chapter 1, 2 and 5 is not new, and we attempt toprovide relevant references. Chapter 3 and 4 is co-authored with J. Ambjrn,while Chapter 6 is co-authored with J. Ambjrn, A. Gorlich and H.-G. Zhang.

AB - The topic of this thesis is quantum gravity in 1 + 1 dimensions. We will focuson two formalisms, namely Causal Dynamical Triangulations (CDT) and Dy-namical Triangulations (DT). Both theories regularize the gravity path integralas a sum over triangulations. The difference lies in the class of triangulationsconsidered. While the CDT triangulations have a natural Lorentzian structure,in DT the triangulations are Euclidean.The thesis is built up around three papers, reproduced as Chapter 3, 4 and 6.The outline is as follows: The rst two chapters provides background materialon path integral quantization and the CDT formalism. In Chapter 3 we considera generalization of CDT (introduced in Ref. [43]) and show that the continuumlimit is the same as for plain CDT. This provides evidence for the robustness ofthe CDT universality class. Chapter 4 provides an analysis of CDT coupled toYang-Mills theory. In Chapter 5 we review the DT formalism and some basicaspects of Liouville Theory. We put special emphasis on some subtleties of thecontinuum limit. Finally, Chapter 6 contains a discussion on mixing betweengeometrical and matter degrees of freedom, when DT is coupled to non-unitaryCFTs.Most of the material in Chapter 1, 2 and 5 is not new, and we attempt toprovide relevant references. Chapter 3 and 4 is co-authored with J. Ambjrn,while Chapter 6 is co-authored with J. Ambjrn, A. Gorlich and H.-G. Zhang.

UR - https://soeg.kb.dk/permalink/45KBDK_KGL/fbp0ps/alma99122291806405763

M3 - Ph.D. thesis

BT - Quantum Gravity in Two Dimensions

PB - The Niels Bohr Institute, Faculty of Science, University of Copenhagen

ER -