4d Simplicial quantum gravity: matter fields and the corresponding effective action
Abstract
Fourdimensional simplicial quantum gravity is modified either by coupling it to U(1) gauge fields or by introducing a measure weighted by the orders of the triangles. Strong coupling expansion and Monte Carlo simulations are used. Although the two modifications of the standard puregravity model are apparently very distinct, they produce strikingly similar results, as far as the geometry of random manifolds is concerned. In particular, for an appropriate choice of couplings, the branched polymer phase is replaced by a crinkled phase, characterized by the susceptibility exponent γ<0 and the fractal dimension d_{H}>2. The quasiequivalence between the two models is exploited to get further insight into the extended phase diagram of the theory.
 Publication:

Physics Letters B
 Pub Date:
 July 1998
 DOI:
 10.1016/S03702693(98)006753
 arXiv:
 arXiv:heplat/9804011
 Bibcode:
 1998PhLB..432..279B
 Keywords:

 High Energy Physics  Lattice
 EPrint:
 12 pages Latex2e, including 4 figures in postscript