Minimum length scale and quantum black holes

The idea that the Planck length can act as a regulator of UV divergences has inspired various approaches to quantum gravity, but a possibly much larger width for the ground state emerges in the (non-perturbative) quantisation of the Oppenheimer-Snyder model of dust collapse that naturally recovers Bekenstein’s area law. The effective geometry for such quantum black holes can then be obtained from coherent states which describe integrable singularities without inner horizons. The extension to quantum rotating black holes with similar properties is briefly described.