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arXiv · hep-lat/9809028

Further Evidence of a Smooth Phase in 4D Simplicial Quantum Gravity

H. S. Egawa·A. Fujitsu·S. Horata·N. Tsuda·T. Yukawa
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Abstract

Four-dimensional (4D) simplicial quantum gravity coupled to U(1) gauge fields has been studied using Monte-Carlo simulations. A negative string susceptibility exponent is observed beyond the phase-transition point, even if the number of vector fields (NV) is 1. We find a scaling relation of the boundary volume distributions in this new phase. This scaling relation suggests a fractal structure similar to that of 2D quantum gravity. Furthermore, evidence of a branched polymer-like structure is suggested far into the weak-coupling region, even for NV > 1. As a result, we propose new phase structures and discuss the possibility of taking the continuum limit in a certain region between the crumpled and branched polymer phases.

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H. S. Egawa, A. Fujitsu, S. Horata, N. Tsuda, T. Yukawa. 1998-09-05. Further Evidence of a Smooth Phase in 4D Simplicial Quantum Gravity. https://doi.org/10.1016/s0920-5632(99)85206-2

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