Scott Manley @DJSnM:
Here's a paper from 1991 that asks what would happen if the laws of physics changed and photons acquired a tiny mass. Light would still work, atoms would still exist, but electric fields might not extend far enough for nerves to work:
mass that is of the order of corresponding to a Compton wavelength of a centimeter. The effects of such a transition on our civilization are examined. All long- range electric and magnetic fields would vanish, as would all low- frequency electromagnetic waves.
Atomic structure and solar radiation would not be appreciably affected. Effects on neural transmission might be serious, depending on the precise value of
the photon mass. It is concluded
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