History of Physics

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Greek physics

Classical mechanics: Newton, Lagrange, Hamilton

Electromagnetism: Green, Maxwell

Around the turn of the 20th century, many unanswered questions had surface in physics: light seemed to move at the same speed rather than relative to an aether; the w:photoelectric effect and the black-body radiation spectrum were both insufficiently explained by classical mechanics.

A major step towards resolving these issues came when Max Planck derived the black-body spectrum using what he considered a calculational trick: he treated the light as if the energy could only be discrete, quantized, values.

In 1905, w:Albert Einstein produced three landmark papers on w:Brownian motion, the photoelectric effect, and w:special relativity. The first paper supported both the atom theory of matter and the fledgling field of statistical mechanics by showing that Brownian motion in a fluid was the result of random motions of atoms. The second paper, which for the first time proposed that light actually is composed of discrete particles, called w:photons, laid the groundwork for quantum mechanics. The third paper introduced the field of special relativity.

Quantum Mechanics: Bohr, Schroedinger, Dirac, etc.

Strange and charming quarks came much later. Later it became apparent that these two theories QM (Quantum Mechanics} and GTR (General Theory of Relativity) are in conflict. w:John Bell, with his w:Bell Theorem, provided the proof that the conflict, sometime called Quantum weirdness, cannot be fixed.

Still later, strings came into the picture.

Now, these two theorist clans can have tea and stuff together, since they may agree. However, there is some question as to what

'the Theory of Everythings'

says about the real world, if anything.