Thought, Function, and Form: The Language of Physics

Time is a linear track for mortal man and ideas and developments have a 'chronological' order that forms a timeline of events that is called history.  The history of quantum theory is defined by a 101 year old history that starts with Max Planck's publication in the year 1900.  This timeline is done as concise map of events that has formed the history of quantum science.

Most historians of science place the beginnings of quantum theory at 1900 with publication of Max Planck's formula for the distribution of energy as a function of frequency in black-body radiation (Davis and Betts, 1994: 1).  This concept that light can be emitted or absorbed only in the form of certain discrete energy packages is a development from earlier studies by Boltzmann, Maxwell, Gibbs and others on the statistical description of the thermal properties of material bodies (Gamow, 1966: 6).  In 1905 Einstein proposed that light itself was quantized, that light consists of particles localized in space, that was later termed photons (Schommers, 1995: 18). 

Next came three models of the atom.  Rutherford's (1911) scattering experiments showed a 'planetary' picture of atoms with electrons moving around the nucleus like a planet around the sun (Schommers, 1995: 20-21).  Bohr's (1913) model improved on the Ruthford model in that the quantum picture was incorporated by the inclusion of two postulates: the postulate of stationary states and the frequency postulate (Schommers, 1995: 21-22). 

Sommerfeld's (1916) model included relativistic effects into Bohr's model (Schommers, 1995: 23).  Bohr's Correspondence Principle (1920) proved that quantum rules correspond to classical rules of physics.  De Broglie's (1923) Wave-Particle Dualism proposed that a particle could also act as a wave (Schommers, 1995: 26-27). 

Heisenberg's (1925) Matrix Mechanics makes the operators time dependent (Schommers, 1995: 33).  Schrodinger's (1926) Wave Mechanics is the equivalent of Heisenberg's but the time dependence is transferred to the wave functions (Schommers, 1995: 30-33).  Born's (1926) Probability Interpretation of the wave function interpreted the individual objects recorded by equipment during an experiment as being true 'corpuscles' (Schommers, 1995: 36-37).  Heisenberg's (1927) Uncertainty Relations states that the more marked a wave character becomes, the more vague the corpuscular aspect becomes and visa versa (Schommers, 1995: 44-45).  Bohr's Complementary Principle (1927) states that in nature both light and elementary particles can appear as waves or corpuscles depending on the type of experiment performed on them (Schommers, 1995: 44-45). 

There are only two theories proposed after 1927 that have some merit towards thinking about quantum theory; Bohm's (1952, 1966) 'Hidden Variables' theory and Everett III (1957) 'Many-Worlds' theory.  The major ideas of quantum theory were formed in the years 1925-1926 by Schrodinger and Heisenberg.