The Ultraviolet Catastrophe
The first crack in the edifice of classical physics came with
attempts to explain the colour of hot objects using classical physics and
electromagnetism. The light from these objects is a mixture of different
frequencies (colours). Observations reveal that such objects have a distinctive
spectrum (pattern of energy distribution at different frequencies). However attempts to explain this in
classical terms failed abjectly - they predicted instead that the amount of
energy would tend towards infinity at the high-energy (violet) end of the
spectrum - an ultraviolet catastrophe.
Enter Max Planck.
In 1900 he suggested that physics should abandon the assumption that
electromagnetic energy is continuous and wavelike. If, instead, energy can only
be absorbed and emitted in discrete packets (or quanta), theory can be made to
fit observations exactly. However, while his suggestion certainly gave the
right answer, its abandonment of a cherished assumption of classical physics
gave it an air of contrivance that led to its relative neglect for several
years.
Email
link | Feedback | Contributed by: Dr.
Christopher Southgate
Source: God, Humanity and the
Cosmos (T&T Clark, 1999)
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