Overview

This period saw classical physics achieve magnificent success (thermodynamics, Maxwell's equations) while it ran into puzzling phenomena it could not explain. Mainstream physics responded by abandoning mechanism for quantum abstraction. The AAM offers mechanical alternatives.

It was also the last period in which the leading physicists still tried to build matter and its forces out of the motion of a medium. Those programmes were set aside by 1900, but the fluid mechanics they worked out is still correct, and it is the mechanics an aether made of real matter has to obey.

Papers in This Section

Forces Through a Fluid: Bjerknes, Kelvin, Hicks and Maxwell (1858\(\unicode{x2013}\)1906)

Helmholtz and Kelvin's vortex rings, Bjerknes's pulsating spheres, Hicks and Hill's vortices, and Maxwell's molecular vortices, read for one question: which forces through a fluid make two bodies attract, then hold apart at a definite distance?

Topics to Come

Each of these challenges revealed the atomic world's complexity, but none required abandoning mechanism. Papers on them will be added to this section.

Physics

  • Maxwell's equations (1864) \(\unicode{x2014}\) electricity, magnetism and light unified, but what is a field?
  • Hertz (1887) \(\unicode{x2014}\) electromagnetic waves confirmed experimentally
  • Michelson\(\unicode{x2013}\)Morley (1887) \(\unicode{x2014}\) the null result that led physics to give up the medium
  • Spectral lines (Balmer 1885, Rydberg 1888) \(\unicode{x2014}\) mechanical resonances
  • Electron discovery (Thomson 1897) \(\unicode{x2014}\) what the measured particle actually is
  • Photoelectric effect \(\unicode{x2014}\) resonant energy transfer without photons
  • Blackbody radiation (Planck 1900) \(\unicode{x2014}\) mechanical mode restrictions
  • X-rays (R\(\unicode{x00f6}\)ntgen 1895) \(\unicode{x2014}\) high-frequency waves in the aether
  • Radioactivity (Becquerel 1896, Curie 1898) \(\unicode{x2014}\) nuclear mechanical instability

Chemistry

  • Chemical spectroscopy (Bunsen and Kirchhoff, 1859) \(\unicode{x2014}\) every element's spectral fingerprint
  • The periodic table (Mendeleev, 1869) \(\unicode{x2014}\) orbitron shell patterns
  • Valence and chemical bonding \(\unicode{x2014}\) mechanical orbital interactions

Astronomy

  • Stellar spectroscopy \(\unicode{x2014}\) a universal composition shows universal physics

Key insight: classical physics challenges required deeper understanding, not abandonment of mechanism. The next period (the Quantum Revolution) shows how physics chose abstraction instead, and where the AAM diverges most strongly.