the.com/logarithm
the math trick that turned impossible multiplication into addition and saved astronomers from going insane
means A mathematical function that tells you the power to which a fixed number (the base) must be raised to produce a given number, turning multiplication into addition and division into subtraction.
from Coined in the early 17th century by the Scottish mathematician John Napier, who stitched together two Greek words: logos, meaning 'ratio' or 'reckoning,' and arithmos, meaning 'number.' So a logarithm is, quite literally, a 'ratio-number' — Napier's name for the clever bookkeeping of proportions that let weary astronomers and navigators trade grinding multiplication for gentle addition.
- inventor
- John Napier spent 20 years building the first tables
- slide rules
- powered engineering and Apollo missions for centuries
- human ears
- perceive loudness logarithmically, not linearly
- earthquakes
- each Richter point means ten times the shaking
- the e base
- appears naturally in growth, decay, and compound interest
briggs logarithm — base-10 logarithm system developed by henry briggs in 1617 for navigation and astronomy
natural logarithm — base-e logarithm system used throughout calculus and physics, discovered by john napier around 1614