Fixed points of quantum gravity in extra dimensions
We study quantum gravity in more than four dimensions with renormalisation group methods. We find a non-trivial ultraviolet fixed point in the Einstein-Hilbert action. The fixed point connects with the perturbative infrared domain through finite renormalisation group trajectories. We show that our results for fixed points and related scaling exponents are stable. If this picture persists at higher order, quantum gravity in the metric field is asymptotically safe. We discuss signatures of the gravitational fixed point in models with low-scale gravity and compact extra dimensions.
Abstract The aim of the present paper is to give the main characteristics of the finite-source G / M /r queue in equilibrium. Here unit i stays in the source for a random time having general distribution function F i ( x ) with density f i ( x ). The service times of all units are assumed to be identically and exponentially distributed random variables with means 1/μ. It is shown that the solution to this G / M /r model is similar in most important respects to that for the M/M/ r model.