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Phase Structure of Four-dimensional Simplicial Quantum Gravity with a U(1) Gauge Field

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

The phase structure of four-dimensional simplicial quantum gravity coupled to U(1) gauge fields has been studied using Monte-Carlo simulations. The smooth phase is found in the intermediate region between the crumpled phase and the branched polymer phase. This new phase has a negative string susceptibility exponent, even if the number of vector fields (Nv) is 1. The phase transition between the crumpled phase and the smooth phase has been studied by a finite size scaling method. From the numerical results, we expect that this model (coupled to one gauge field) has a higher order phase transition than first order, which means the possibility to take the continuum limit at the critical point. Furthermore, we consider a modification of the balls-in-boxes model for a clear understanding of the relation between the numerical results and the analytical one.

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S. Horata, H. S. Egawa, N. Tsuda, T. Yukawa. 2000-04-23. Phase Structure of Four-dimensional Simplicial Quantum Gravity with a U(1) Gauge Field. https://doi.org/10.1143/ptp.106.1037

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