Some black holes actually preserve quantum superpositions — not destroy them

Black holes are usually expected to collapse quantum superpositions through gravitational decoherence — but maximally charged (near-extremal) black holes behave differently. Quantum fluctuations near their horizons create an energy gap in the black hole's own spectrum, which at low temperatures drives the decoherence rate to zero. Even above the gap, decoherence is suppressed below semiclassical predictions, meaning the right kind of black hole actually protects quantum coherence rather than destroying it.