Active range control of emitter-absorber coupling. Antennas, mirrors, resonators and biased receivers, and what time reversal does and does not exchange

Absorber influence on emitter has several different scales, not one range: separation (Förster nm, antennas, plasmons µm, far field any), coherence length only for mirror interference - returning photon is reabsorbed at any distance, cQ/ω is storage time not reach, bias sets sign of exchange. Bias switching is not CPT - separated scattering reversal (matched capture) from retrodiction, both calculated; Partridge test starts where calibrated ordinary response is below sensitivity.