|"The energy of the universe is constant."|
|(first main principle)|
|"The entropy of the universe tends to a maximum."|
|(second main principle)|
“Thermodynamics is the study of the principles and laws behind the phenomenon of the production of motion by heat, considered from a sufficiently general point of view, applicable to not only steam engines, but to all imaginable heat engines, whatever the working substance and whatever the method by which it is operated.”
|A 1931 meeting of the minds "thermodynamics" dinner party photoshowing, from left to right, thermodynamics founders: Walther Nernst, Albert Einstein, and Max Planck, following by Robert Millikan, grinning, noted for his famous 1909 electron charge determining oil drop experiment, at the house of host Max von Laue, noted relativistic thermodynamics pioneer; in the photo collage can be seen: Ludwig Boltzmann and Rudolf Clausius among others.|
See main: History of thermodynamicsIn a nutshell, thermodynamics is the science, developed largely between 1823 and 1882, that united affinity-chemistry (1718), thermo-chemistry (1870s), thermo-electricity (1822), overthrew the caloric theory, vitalism, perpetual motion theory (replacing them with the kinetic theory, mechanical equivalent of heat, and the conservation of energy respectively), and later functioning to seed the quantum revolution (1900).
“If we say, in the words of Maxwell some years ago (1878), that thermodynamics is ‘a science with secure foundations, clear definitions, and distinct boundaries,’ and ask when those foundations were laid, those definitions fixed, and those boundaries traced, there can be but one answer. Certainly not before the publication of that memoir (Clausius, 1850).”
See main: Timeline of thermodynamicsVisit the moving (sideways scrolling) twenty-foot long pictorial timeline of thermodynamics, a portion of which is shown below, for a quick visual history of thermodynamics:
See main: Definitions of thermodynamicsThe following is partial chronological listing of definitions of thermodynamics:
“It is a matter of ordinary observation, that heat, by expanding bodies, is a source of mechanical energy; and conversely, that mechanical energy, being expended either in compressing bodies, or in friction, is a source of heat. The reduction of the laws according to which such phenomena take place, to a physical theory, or connected system of principles, constitutes what is called the science of thermodynamics.”
|William Rankine |
|1880||“Thermodynamics, or the mechanical theory of heat, is that science which treats of the mechanical effects of heat, and of those mechanical processes by which heat is generated.”||Robert Rontgen and Augustus du Bois |
|1998||“Thermodynamics now designates the science of all transformations of matter and energy.”||Pierre Perrot |
See main: Branches of thermodynamicsThermodynamics has it roots in affinity chemistry (1718), thermo-chemistry (1770s), thermo-electricity (1822), thus becoming a tree with foundations in the works of Sadi Carnot, William Thomson, Rudolf Clausius (trunk), and William Rankine, soon thereafter sprouting many branches of thermodynamics, e.g. biological thermodynamics (1926), each with many sub-branches, e.g. protein thermodynamics (1960s).
|Visuwords word-association definition of thermodynamics, showing key terms: adiabatic, process, cycle, heat, enthalpy, thermostatics, equilibrium, entropy, and physics. |