Information gap for classical and quantum communication in a Schwarzschild spacetime
Physical Review A 85, 042312 (2012)
Communication between a free-falling observer and an observer hovering above the Schwarzschild horizon of a black hole suffers from Unruh-Hawking noise, which degrades communication channel capacities. Ignoring time dilation, which affects all channels equally, we show that for bosonic communication using single and dual rail encoding the classical channel capacity reaches a finite value and the quantum channel capacity tends to zero. We conclude that classical correlations still exist at infinite acceleration, whereas the quantum coherence is fully removed..