Redefining Reality - The Intellectual Implications of Modern Science

Einstein rejected the idea of a
luminiferous aether, preferring
a picture of reality that he
thought was simpler.
Consider a magnet and
a coil of wire that is
connected to a circuit. If
you hold the coil of wire
still and move the magnet
back and forth inside,
you create a current in the
circuit. If you hold the
magnet still but move the
coil around the magnet
at the same rate, you
get the same current. It
doesn’t matter which one
is moving, just that they
move relative to each other.
© Library of Congress, Prints and Photographs Division, LC-USZ62-60242.
But Maxwell’s equations give different explanations for the
different cases, different explanations if we assume there is an
aether. If we reject the aether, then all that matters is the relative
state of motion. The different explanations of the current are
not really different, just different ways of describing the same
thing from different perspectives.
second is the principle of relativity, according to which the laws
of physics are the same for all observers who are not accelerating
relative to each other.
that allow us to translate between physical descriptions that
would be offered by different observers. As the Dutch physicist
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