%0 Journal Article %T Further Evidence of a Smooth Phase in 4D Simplicial Quantum Gravity %A H. S. Egawa %A A. Fujitsu %A S. Horata %A N. Tsuda %A T. Yukawa %J Physics %D 1998 %I arXiv %R 10.1016/S0920-5632(99)85206-2 %X 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. %U http://arxiv.org/abs/hep-lat/9809028v1