combinations of quarks that we think are indivisible.
Jonathan Swift wrote that “a flea
Has smaller fleas that on him prey”
and “ad infinitum,” which
means,
if it were true, that the impossible end of density,
and the impossible medium in which
smaller and smaller parts
continue to vibrate, could make it
difficult to imagine the indivisible.
J. J. Tomson and others had already taught that atoms have
parts. Planck and Einstein were at work to explain what those
parts were and how they worked.
Planck studied how hot objects emit light; he called the
packets of radiation emitted by black bodies “bundles”
or “energy elements.” Einstein studied how metal
surfaces that absorb light emit electrons; he calculated that
photons had to be quantized. All elecromagnetic radiation is
absorbed and emitted in discrete packets, that is, in quanta.
J. J. Tomson and others had already taught that atoms have parts. Planck and Einstein were at work to explain what those parts were and how they worked.
Planck studied how hot objects emit light; he called the packets of radiation emitted by black bodies “bundles” or “energy elements.” Einstein studied how metal surfaces that absorb light emit electrons; he calculated that photons had to be quantized. All elecromagnetic radiation is absorbed and emitted in discrete packets, that is, in quanta.
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