Fifteen
Maxwell's Silver
Hammer
In considering questions as remote as the origin of life, science must
skate toward new shores across the thin ice of speculation, but it also has
a duty to warn us of present dangers as specifically as possible. Since the
earth's electromagnetic activity has such a profound effect on life, the
obvious question is: What are the consequences of our artificial energies?
Electromagnetism can be discussed in two ways—in terms of fields
and in terms of radiation. A field is "something" that exists in space
around an object that produces it. We know there's a field around a
permanent magnet because it can make an iron particle jump through
space to the magnet. Obviously there's an invisible entity that exerts a
force on the iron, but as to just what it consists of—don't ask! No one
knows. A different but analogous something—an electric field—extends
outward from electrically charged objects.
Both electric and magnetic fields
are static, unvarying. When the
factor of time is introduced, by varying the intensity of the field as in a
radio antenna, an electromagnetic field results. As its name implies, this
consists of an electric field and a magnetic field. The fluctuations in the
field radiate outward from the transmitter as waves of energy, although
somehow these waves simultaneously manage to behave as streams of
massless, chargeless particles (photons). As to just how this happens,
again—don't ask! Sometimes the phenomenon is called an electromag-
netic
field (EMF), to emphasize its connection with the transmitter;
sometimes it's called electromagnetic radiation (EMR), to emphasize its