The quantity of
energy no longer available to do physical work. Every real process converts energy into both work or a condensed form of energy and waste. Some waste may be utilized in processes other than those generating it (
see recycling ) but the ultimate waste which can no longer support any process is energy in the form of dispersed heat (
see second law of thermodynamics ). All physical process, despite any local and temporal concentration of energy they may achieve, contribute to the increased overall dispersion of heat. Entropy therefore irreversibly increases in the known universe. (
Krippendorff )
