The schoolbook picture — electric and magnetic fields at right angles, travelling outward, fading with the square of the distance — is the far field. It is what the wave looks like once it has left home. Biology never meets that wave. Biology lives within a few diameters of the source, where the fields are tangled, fade far faster, and store energy rather than carry it away.
audited ground
Far from a source, the electromagnetic wave settles into its travelling form: the fields perpendicular to each other and to the direction of travel, energy carried outward, intensity falling as the square of the distance. This is real — but it is the wave after it has departed.
audited ground
Within a wavelength or so of the source, the fields have not settled. They are tangled, they fade much faster than the square law, and they store energy near the source instead of radiating it. The neat diagram is not wrong; it is a portrait of somewhere else.
audited ground
Membranes, proteins, and the water between them sit at nanometre distances from their charges — deep inside the near zone of every molecular source. The physics the cell actually lives in is the tangled, storing, fast-fading kind.
