A black hole cast on a non-commutative background
arXiv:1007.5342
Abstract
In this work we describe a black hole, set on a non-commutative background. The model, which is relatively simple, is an exact solution of the Einstein Field Equations. Based on a proposition we put forward, we argue that introducing a matter density field on a non-commutative background sets up a mechanism that deforms the field into two distinct fields, one residing dominantly on the lattice tops (hereafter, on-cell) and the other residing dominantly in the inter-lattice regions (hereafter, off-cell). The two fields have different physical and themodynamic characterics which we describe, and some of which play a role in halting collpse to a singularity. For example, not surprisingly the on-cell (off-cell) fields manifest standard on-shell (off-shell) characteristics, respectively. Both the density and the net mass-energy are unchanged by the deformation mechanism. In our treatment the mass of a black hole defines its own size scale L of the interior region it occupies. Moreover, such a length is quantized, L=2N\sqrtθ, in terms of a minimum length scale \sqrtθ. The approach has the advantage that there is no degeneracy in mass-confinement since, here, the black hole density is not a function of the mass (as is the case in some recent treatments). The density is, instead a fixed quantity. As such, the approach puts an upper bound on black hole density, making it a universal parameter. The picture that emerges is that a black hole defined on a non-commutative background is both non-singular, holographic and quantized. Yet we also find, interestingly, that when taken over L the average value of the associated energy-stress tensor of the fields satisfies all classical energy conditions of GR.
Expanded version of presentation made at 19th International Conference of General Relativity and Gravitation. Small changes in abstract, introduction and some references added