Definition of critical mass

The term "critical mass" originated in the field of nuclear physics, where it refers to the minimum number of fissile materials required in a nuclear reactor to sustain a self-sustaining nuclear chain reaction. The term was adopted and popularized in the 1960s by the environmental activist group Climate Action, to describe the point at which a grassroots social movement becomes self-organized, self-sustaining, and powerful enough to bring about significant social change. In essence, it suggests that when critical mass is reached, the momentum and impact of the movement grow exponentially, like a chain reaction, making it difficult to ignore or resist their demands. In other words, critical mass is the threshold beyond which a movement can become a catalyst for large-scale political and social transformations, ultimately forcing the authorities to meet the demands of the people.