Meaning
The minimum amount of something - people, support, adoption, evidence - needed for a process to become self-sustaining and take off on its own. Borrowed from nuclear physics, it marks the threshold at which a slow build-up suddenly fuels itself: enough users, and the network sells itself. Standard in business, activism, and network-economics talk; the cycling protest movement Critical Mass borrows the term directly. Regional use: General English; physics parent term, American academic figurative adoption.
Origin
In nuclear physics, critical mass is the minimum quantity of fissile material needed to sustain a chain reaction, the quantity calculated at Los Alamos and kept in mind ever since. The sociological borrowing was built by Thomas Schelling and Mark Granovetter: Schelling's 1971 segregation models used a related critical density for pollution and his 1978 book Micromotives and Macrobehavior refined the idea, while Granovetter's 1978 threshold models of collective behavior supplied the mechanism. The label arrived with Oliver, Marwell, and Teixeira's 1985 paper A Theory of Critical Mass, and M. Lynne Markus's 1987 critical-mass theory of interactive media carried it into technology marketing - the fax machine's 1987 breakthrough, when Americans began assuming everybody else had one, remains the textbook example. Wiktionary now records the plain figurative sense - the minimum number needed to trigger a phenomenon - with Marwell and Oliver's 1993 book as a standing citation.
Research Sources
References used to check this entry’s meaning, history, or documented forms.
Variants
- achieve critical mass
- critical mass of support
- reach critical mass
Usage Examples
- The toolchain only became useful once it reached critical mass: with twenty colleagues on it, the rest followed in a month.
- The campaign needed a critical mass of signatures before the newspapers would treat it as news.
- Two hundred cyclists riding together made a critical mass that no driver could ignore.