1993/08/26 by Christof Schmidhuber, Schmidhuber, Christof, Caltech Ph. D. thesis +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #hep-th
paper · pdf · doi:10.48550/arxiv.hep-th/9308121
75 pages, Tex
arxiv created 1993/08/26 · arxiv updated 2009/11/30
The theory of embedded random surfaces, equivalent to two--dimensional quantum gravity coupled to matter, is reviewed, further developed and partly generalized to four dimensions. It is shown that the action of the Liouville field theory that describes random surfaces contains terms that have not been noticed previously. These terms are used to explain the phase diagram of the Sine--Gordon model coupled to gravity, in agreement with recent results from lattice computations. It is also demonstrated how the methods of two--dimensional quantum gravity can be applied to four--dimensional Euclidean gravity in the limit of infinite Weyl coupling. Critical exponents are predicted and an analog of the ``c=1 barrier'' of two--dimensional gravity is derived.