Quantum phase transitions and the breakdown of classical general relativity

It is proposed that the infinite-red-shift surface of a black hole is a quantum phase transition of the vacuum of space-time analogous to the liquid-vapour critical point of a Bose fluid. The equations of classical general relativity remain valid arbitrarily close to the horizon yet fail there through the divergence of a characteristic coherence length xi. The integrity of global time. required for conventional quantum mechanics to be defined, is maintained. The metric inside the event horizon is different from that predicted by classical general relativity and may be de Sitter space. The deviations from classical behaviour lead to distinct spectroscopic and bolometric signatures that can, in principle, be observed at large distances from the black hole.