Kinetic Theory of the Dissipation of Energy

• DOI: 10.1038/009441c0
• Publication Date: 2008-01-03T10:13:22Z
• Authors: WILLIAM THOMSON
• Keywords: Mechanical energy

The equations of motion in abstract dynamics are perfectly reversible; any solution of these equations remains valid when the time variable t is replaced by - t. Physical processes, on the other hand, are irreversible: for example, the friction of solids, conduction of heat, and diffusion. Nevertheless, the principle of dissipation of energy is compatible with a molecular theory in which each particle is subject to the laws of abstract dynamics.