Gravitational radiation in quantum gravity

Gravitational collapse in loop quantum gravity

In this paper we study the gravitational collapse in loop quantum gravity. We consider the space-time region inside the Schwarzschild black hole event horizon and we divide this region in two parts, the first one where the matter (dust matter) is localized and the other (outside) where the metric is Kantowski-Sachs type. We calculate the state solving Hamiltonian constraint and we obtain a set ...

Gravitational Wilson Loop in Discrete Quantum Gravity

Results for the gravitational Wilson loop, in particular the area law for large loops in the strong coupling region, and the argument for an effective positive cosmological constant, discussed in a previous paper, are extended to other proposed theories of discrete quantum gravity in the strong coupling limit. We argue that the area law is a generic feature of almost all non-perturbative lattic...

Gravitational phase transitions in infrared quantum gravity

The conformal anomaly induced sector of four-dimensional quantum gravity (infrared quantum gravity) —which has been introduced by Antoniadis and Mottola— is here studied on a curved fiducial background. The one-loop effective potential for the effective conformal factor theory is calculated with accuracy, including terms linear in the curvature. It is proven that a curvature induced phase trans...

Gravitational-wave probe of effective quantum gravity

Pulsar Radiation and Quantum Gravity

Quantum gravity may lead to an energy dependence in the speed of light. The high energy radiation from gamma-ray pulsars can be used to place limits on such effects. We find that emission from the Crab pulsar at energies above 2 GeV trails that at 70–100 MeV by no more than 0.35 ms (95% confidence) and place a lower bound on the energy scale of quantum gravitational effects on the speed of ligh...