Do black hole surfaces flicker like quantum light?

Einstein once proved light comes in quanta by analyzing how blackbody radiation fluctuates — now the same logic is applied to the boundary of a causal diamond (a light-cone-bounded region of spacetime). The calculation produces an area-fluctuation formula with two terms: one classical, one linear in the average area — exactly the statistical fingerprint of discrete, independent constituents. Just as Einstein's linear energy term pointed to photons, this linear area term points to indivisible 'pixels' of spacetime geometry.