| 20645 | Heat is a state of vibration, not a substance [Joule] |
| Full Idea: We consider heat not as a substance but as a state of vibration. | |
| From: James Joule (works [1870]), quoted by Peter Watson - Convergence 01 'Nature's' | |
| A reaction: The puzzle is that giving accurate accounts of vibrations, heat and movement require a quantitative substance, energy. But all we have here is movement, and the denial of a substance. Energy is 'nature's currency system'. |
| 20972 | Joule showed that energy converts to heat, and heat to energy [Joule, by Papineau] |
| Full Idea: James Joule established the equivalence of heat and mechanical energy, in the sense of showing that a specific amount of heat will always be produced by the expenditure of a given amount of energy, and vice versa. | |
| From: report of James Joule (works [1870]) by David Papineau - Thinking about Consciousness App 4.2 | |
| A reaction: This was a major step towards the law of conservation of energy. |
| 20624 | Work degrades into heat, but not vice versa [Close] |
| Full Idea: William Thomson, Lord Kelvin, declared (in 1865) the second law of thermodynamics: mechanical work inevitably tends to degrade into heat, but not vice versa. | |
| From: Frank Close (Theories of Everything [2017], 3 'Perpetual') | |
| A reaction: The basis of entropy, which makes time an essential part of physics. Might this be the single most important fact about the physical world? |