Zusammenfassung
Quantum gravity is investigated in the limit of a large number of space-time
dimensions, using as an ultraviolet regularization the simplicial lattice path
integral formulation. In the weak field limit the appropriate expansion
parameter is determined to be $1/d$. For the case of a simplicial lattice dual
to a hypercube, the critical point is found at $k_c/łambda=1/d$ (with $k=1/8
G$) separating a weak coupling from a strong coupling phase, and with $2
d^2$ degenerate zero modes at $k_c$. The strong coupling, large $G$, phase is
then investigated by analyzing the general structure of the strong coupling
expansion in the large $d$ limit. Dominant contributions to the curvature
correlation functions are described by large closed random polygonal surfaces,
for which excluded volume effects can be neglected at large $d$, and whose
geometry we argue can be approximated by unconstrained random surfaces in this
limit. In large dimensions the gravitational correlation length is then found
to behave as $| (k_c - k) |^1/2$, implying for the universal
gravitational critical exponent the value $\nu=0$ at $d=ınfty$.
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