A courier delivers packages to a building with two entrances. While the door is open, he freely enters both. But once one door starts to close, getting inside becomes harder and harder. That's roughly how information behaves at a black hole's horizon — the invisible boundary from which nothing can escape.
In the new study, scientists described this process as two opposing flows. One flows outward, toward us, and as gravity strengthens (the parameter spacetime curvature grows), it weakens — quantum entanglement and other resources diminish. The second flow goes inward, into the inaccessible region, where resources, conversely, accumulate. It's like communicating vessels: as much as leaks from one, that much arrives in the other.
The authors tested the idea using quantum coherence — the ability of particles to exist in multiple states at once, like a juggler keeping several balls in the air. In an expanding universe with a charged black hole, coherence outside decreased while inside it grew, exactly following the prediction. This explains why earlier calculations saw monotonous trends: the reason lies not in details but in the general order dictated by the horizon itself.
Quantum coherence at a black hole's horizon decreases outside and increases inside, like water in communicating vessels: as much as leaks from one, that much arrives in the other.
In Michael Crichton's novel "Sphere," an alien artifact warps space, and the characters find that the laws of physics change near it — much like quantum resources at the horizon.