Weaving a classical metric with quantum threads
Abstract
Results that illuminate the physical interpretation of states of nonperturbative quantum gravity are obtained using the recently introduced loop variables. It is shown that (i) while local operators such as the metric at a point may not be well defined, there do exist nonlocal operators, such as the area of a given twosurface, which can be regulated diffeomorphism invariantly and which are finite without renormalization; (ii) there exist quantum states which approximate a given metric at large scales, but such states exhibit a discrete structure at the Planck scale.
 Publication:

Physical Review Letters
 Pub Date:
 July 1992
 DOI:
 10.1103/PhysRevLett.69.237
 arXiv:
 arXiv:hepth/9203079
 Bibcode:
 1992PhRvL..69..237A
 Keywords:

 04.60.+n;
 High Energy Physics  Theory
 EPrint:
 9 pages, no figures