Pringsheim
Full Name: Ernst Pringsheim
Achievements: His work led to quantum theory.
Born: July 11, 1859; Breslau, Germany (now Wroclaw, Poland)
Died: June 28, 1917; Breslau, Germany (Aged 57)
Field & Discipline: Science; Physics
Language: German
Father: Siegmund Pringsheim
Mother: Anna Guradze
Siblings: Unknown
Spouse: Unknown
Children: Unknown
Education: Magdalenengymnasium; Johannesgymnasium to 1877; University of
Heidelberg, 1877-78; University of Breslau, 1878-79; University of Berlin, 1879-86
Major Work:
"Uber die Strahlung des schwarzen Korpers fur lange Wellen" (1900)
Life & Times:
At the University of Berlin, Pringsheim began his postgraduate studies in physics and mathematics under its famous professor of physics, [studied under] Helmholtz*, in the autumn of 1879.
Pringsheim's most important work was largely experimental, in the areas of heat and light radiation. While at Berlin, in 1881, Pringsheim developed an infrared spectrometer that made the first accurate measurements of wavelengths in the infrared region.
He first to develop the radiometer (invented by the English physicist [developed radiometer of] Crookes* in 1873-76) into a useful instrument for measuring infrared radiation.
In July 1882 he received his Ph.D. for a dissertation on heat and light radiation, and qualified as a lecturer in physics at Berlin in January 1886. During these early years at Berlin, he investigated (among other things) the chemical effects of light on hydrochloric acid gas, cooperated with the philologist [collaborated with] Schwan* of Jena in his investigation of the French accent, and collaborated with the German lawyer Otto Gradenwitz in the reconstruction of old documents by photography.
At the beginning of the 1890s, Pringsheim became interested in [influenced by] Kirchhoff's* law, which allowed calculation of the currents, voltages, and resistances of electrical networks, and investigated the validity of its limits.
In 1896 he then began to work with Otto Lummer, using his infrared spectrometer, on a study of blackbody radiation - i.e. the energy distribution of radiation emitted by a blackbody (a hypothetical body that completely absorbs all radiant energy falling upon
it, reaches some equilibrium temperature, and then reemits that energy as
quickly as it absorbs it).
In 1859-60 Kirchhoff had defined a blackbody as an object that re-emits all of the radiant energy hitting it; i.e., it is a perfect emitter and absorber of radiation. There was, therefore, something absolute about blackbody radiation, and by the 1890s various experimental and theoretical attempts had been made to find its spectral energy distribution – the curve displaying how much radiant energy is emitted at different frequencies for a given temperature of the blackbody.
In 1896 Wilhelm Wien of the Physikalisch-Technische Reichsanstalt (PTR) in Berlin-Charlottenburg had developed a formula to account for blackbody radiation, and it was Wien's work that led Pringsheim and Lummer to a verification of the law of [verified theory of] Stefan* and [verified theory of] Boltzmann* that relates the energy radiated by a body to its absolute temperature - i.e. that the amount of energy radiated per second from a blackbody is proportional to the fourth power of its thermodynamic (or absolute) temperature. Pringsheim and Lummer then measured the spectral distribution of the radiation energy with the aid of the cylindrical blackbody.
In 1899 Pringsheim and Lummer first confirmed Wien's displacement law, which related the peak frequency of maximum energy to the temperature, but by October 1900 they had found anomalies in this law and definite indications that, while valid at high frequencies, it broke down completely at low frequencies. Their results encouraged [influenced] Planck* to renew his search for a radiation equation that would account for these experimental results.
In late 1900, Planck arrived at this new law by assuming that the energy of the radiation consists of indivisible units that he called 'quanta', a concept that conflicted fundamentally with all past physical theory. This remarkable development marked the founding of the quantum theory, which abandoned classical dynamical principles and
assumed energy changes to take place in violently abrupt instalments, or
quanta.
In 1905 Pringsheim was appointed as Professor of Experimental Physics at the
University of Breslau, where he established a six-term course in theoretical
physics.
Extra Connections: Became interested in [a follower of] Blavatsky’s* Theosophy.
His daughter married [son-in-law was] Mann*.
He was a friend of [a pal of] Wagner*
Assessment: He made important advances in radiation physics at the end of the 19th century and his work was the catalyst for Planck's realization of 'quanta' and the quantum theory.
Oneliner: Ernst Pringsheim, who forshadowed quantum physics
Bibliography:
- Dictionary of Scientific Biography.