Scaling Exponents for Lattice Quantum Gravity in Four Dimensions

Understand

In this work nonperturbative aspects of quantum gravity are investigated using the lattice formulation, and some new results are presented for critical exponents, amplitudes and invariant correlation functions.

• Values for the universal scaling dimensions are compared with other nonperturbative approaches to gravity in four dimensions, and specifically to the conjectured value for the universal critical exponent $\nu =1 /3$.
• It is found that the lattice results are generally consistent with gravitational anti-screening, which would imply a slow increase in the strength of the gravitational coupling with distance, and here detailed estimates for exponents and amplitudes characterizing this slow rise are presented.
• Furthermore, it is shown that in the lattice approach (as for gauge theories) the quantum theory is highly constrained, and eventually by virtue of scaling depends on a rather small set of physical parameters.