Primordial black holes as a probe of the early universe and a varying gravitational constant
Abstract
Description
We discuss recent developments in the study of primordial black holes, focussing particularly on their formation and quantum evaporation. Such studies can place important constraints on models of the early Universe. An especially interesting development has been the realization that such constraints may be severely modified if the value of the gravitational "constant" G varies with cosmological epoch, a possibility which arises in many scenarios for the early Universe. The nature of the modification depends upon whether the value of $G$ near a black hole maintains the value it had at its formation epoch (corresponding to gravitational memory) or whether it tracks the background cosmological value. This is still uncertain but we discuss various approaches which might help to resolve the issue.
Lecture delivered at the Nato Advanced Study Institute: Phase Transitions in the Early Universe: Theory and Observations. Erice 6th-17th December 2000. Eds. H.J.de Vega, I.Khalatnikov, N.Sanchez
Lecture delivered at the Nato Advanced Study Institute: Phase Transitions in the Early Universe: Theory and Observations. Erice 6th-17th December 2000. Eds. H.J.de Vega, I.Khalatnikov, N.Sanchez