hypothesis v. theory v. law

A hypothesis is a tentative explanation for a phenomenon that can be supported or disproven by further investigation.

A theory is a widely accepted explanation for a phenomenon (or a group of phenomena) that is supported by repeated testing. Theories can be used to make predictions about the results of experiments or observations. Examples: the Big Bang theory, plate tectonics, relativity.

A law is a a statement describing a fundamental, invariable relationship in science. Laws can often be expressed as mathematical equations, and describe how things behave, not why they do. Examples: Boyle’s law, Kepler’s laws of planetary motion, Maxwell’s equations.

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