Dr Faustus of Modern Physics - Department of Speech, Music and ...

Chapter 10
Birth of Modern Physics
We have found a strange footprint on the shores of the unknown. We
have devised profound theories, one after another, to account for its
origins. At last, we have succeeded in reconstructing the creature that
made the footprint. And lo! It is our own. (Sir Arthur Eddington
(1882 - 1944) in Space, Time and Gravitation 1920)
10.1 Contradiction of 2nd Law and Radiation
Classical physics culminated in the 19th century on the basis of Calculus laid
by Descartes, Leibniz and Newton and formulated as Hamiltonian mechanics
by the mathematicians Euler and Lagrange.
However, in the late 19th century certain problems within Hamiltonian
mechanics turned up, which seemed impossible to handle using Calculus and
thereby threatened to crush the beautiful building of physics, namely
• the 2nd law of thermodynamics,
and the related problem of
• blackbody radiation.
Both thermodynamics and blackbody radiation in reality showed a fundamental
property of irreversibility with an arrow of time pointing forward, but
Hamiltonian mechanics was seen to be formally reversible and thus without
preferred direction of time. The contradiction between an irreversible reality
and reversible theory put a strong blow to physics, which would be lethal
unless a counterattack could be mounted.
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