# critical mass (threshold)

*Ordinarily means:* A sufficient number of people or things gathered to start a new phase.

When a parameter reaches a wall where the whole exceeds its parts, and drift that was not enough before now carries the thing across.

- Computed level: L15 (depth in the emergence graph, not abstraction)
- Status: review  ·  Domain: social movements, nuclear physics, marketing  ·  Arena: emergence

## Emergence
**Emerges from:** [wall](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-wall.range-end), [drift](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-drift.aimless), [whole](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-whole.complete), [part](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-part.relation), [parameter](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-parameter.condition)

**Through:** interaction.process

**Novel properties:**
- whole.exceeding.parts

## Examples
- In 2008, Iceland's banking sector collapsed when liabilities exceeded seven times GDP, triggering systemic failure. *(economics)*
- The Fukushima Daiichi nuclear reactor achieved prompt criticality after neutron flux passed 1.006, overwhelming control rods. *(engineering)*
- The #MeToo hashtag reached critical mass on Twitter on October 15, 2017, generating over 500,000 mentions in 48 hours. *(computing)*

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*Canonical: https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-critical-mass.threshold*  
*Structured data: https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-critical-mass.threshold.json*  
*Every definition provably resolves to space, time, energy and pattern.*