the.com/conservation of energy
Energy never dies, it just gets worse at its job.
means A law of physics stating that the total energy in an isolated system stays constant—it can change form (motion to heat, chemical to electrical) but is never created or destroyed.
from The principle itself crystallized through 19th-century physics, as scientists like Joule, Helmholtz, and Mayer independently found that heat, motion, and work could convert into one another without any net loss. The word 'energy' traces back to Greek 'energeia,' meaning 'activity' or 'being-at-work,' coined by Aristotle from 'en-' (in) and 'ergon' (work). 'Conservation' comes from Latin 'conservare,' 'to keep, preserve'—the same root behind conserving food or land, here applied to the universe's ledger of work, refusing to let any of it simply vanish.
- real cost
- every transfer leaks some energy as useless heat
- origin
- emerged from 1840s work on steam engines, not philosophy
- loophole
- general relativity lets total energy wobble on cosmic scales
- noether's insight
- it exists because physics looks the same every day