heliocentric theory

the cosmological theory that the sun is the center of the solar system and that the earth and other heavenly bodies orbit around it. The theory, which originated in ancient Greece, was revived by Polish astronomer Nicolaus Copernicus (1475–1543) and elaborated by Italian physicist and astronomer Galileo Galilei (1564–1642). It was controversial in the 16th and 17th centuries because it opposed the traditional doctrine of the Catholic Church that the earth was stationary at the center of the universe (see geocentric theory). Also called Copernican theory.

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Psychology term of the day

September 7th 2024

investment model

a theory explaining commitment to a relationship in terms of one’s satisfaction with, alternatives to, and investments in the relationship. According to the model, commitment is a function of not only a comparison of the relationship to the individual’s expectations but also the quality of the best available alternative and the magnitude of the individual’s investment in the relationship; the investment of resources serves to increase commitment by increasing the costs of leaving the relationship. Although originally developed in the context of romantic associations and friendships and used to explain why people stay in abusive relationships, the investment model has since been extended to a variety of other areas, including employment and education. [proposed in 1980 by U.S. social psychologist Caryl E. Rusbult (1952–2010)]