1.11 Text Thermodynamics, statistical mechanics, and electromagnetic theory
1.11.1 Read the text, translate it and find one extra step in the list of main steps below the text.
The establishment of a mathematical physics of energy between the 1850s and the 1870s expanded substantially on the physics of prior eras and challenged traditional ideas about how the physical world worked. While Pierre-Simon Laplace’s work on celestial mechanics solidified a deterministically mechanistic view of objects obeying fundamental and totally reversible laws, the study of energy and particularly the flow of heat, threw this view of the universe into question.
Figure 7 - William Thomson (1824-1907),
later Lord Kelvin
Drawing upon the engineering theory of Lazare and Sadi Carnot, and Émile Clapeyron; the experimentation of James Prescott Joule on the interchangeability of mechanical, chemical, thermal, and electrical forms of work; and his own Cambridge mathematical tripos training in mathematical analysis; the Glasgow physicist William Thomson and his circle of associates established a new mathematical physics relating to the exchange of different forms of energy and energy overall conservation (what is still accepted as the “first law of thermodynamics”). Their work was soon allied with the theories of similar but less-known work by the German physician Julius Robert von Mayer and physicist and physiologist Hermann von Helmholtz on the conservation of forces.
Figure 8 - Ludwig Boltzmann (1844-1906)
Taking his mathematical cues from the heat flow work of Joseph Fourier (and his own religious and geological convictions), Thomson believed that the dissipation of energy with time (what is accepted as the “second law of thermodynamics”) represented a fundamental principle of physics, which was expounded in Thomson and Peter Guthrie Tait’s influential work Treatise on Natural Philosophy. However, other interpretations of what Thomson called thermodynamics were established through the work of the German physicist Rudolf Clausius. His statistical mechanics, which was elaborated upon by Ludwig Boltzmann and the British physicist James Clerk Maxwell, held that energy (including heat) was a measure of the speed of particles. Interrelating the statistical likelihood of certain states of organization of these particles with the energy of those states, Clausius reinterpreted the dissipation of energy to be the statistical tendency of molecular configurations to pass toward increasingly likely, increasingly disorganized states (coining the term “entropy” to describe the disorganization of a state). The statistical versus absolute interpretations of the second law of thermodynamics set up a dispute that would last for several decades (producing arguments such as “Maxwell's demon”), and that would not be held to be definitively resolved until the behavior of atoms was firmly established in the early 20th century.
Meanwhile, the new physics of energy transformed the analysis of electromagnetic phenomena, particularly through the introduction of the concept of the field and the publication of Maxwell’s 1873 Treatise on Electricity and Magnetism, which also drew upon theoretical work by German theoreticians such as Carl Friedrich Gauss and Wilhelm Weber. The encapsulation of heat in particulate motion, and the addition of electromagnetic forces to Newtonian dynamics established an enormously robust theoretical underpinning to physical observations. The prediction that light represented a transmission of energy in wave form through a “luminiferous ether”, and the seeming confirmation of that prediction with Helmholtz student Heinrich Hertz’s 1888 detection of electromagnetic radiation, was a major triumph for physical theory and raised the possibility that even more fundamental theories based on the field could soon be developed. Research on the transmission of electromagnetic waves began soon after, with the experiments conducted by physicists such as Nikola Tesla, Jagadish Chandra Bose and Guglielmo Marconi during the 1890s leading to the invention of radio.
Main steps of the physical science and mechanics development in the second half of the 19th century:
The new study of energy throws the deterministically mechanistic view of the universe into question.
A new mathematical physics relating to the exchange of different forms of energy and energy’s overall conservation is introduced.
The second law of thermodynamics and other interpretations appeare.
The new physics of energy transformed the analysis of electromagnetic phenomena.
The prediction that light represents a transmission of energy in wave form and some other scientific events raise the possibility that even more fundamental theories based on the field could be developed.
After the publication of Maxwell’s 1873 Treatise on Electricity and Magnetism a new self-propelled vehicle is built.
The research on the transmission of electromagnetic waves during the 1890s leads to the invention of radio.