The Four Postulates

The Four Postulates are foundational principles in quantum mechanics that describe how particles behave. First, each particle's state is described by a mathematical object called a wave function. Second, the wave function evolves smoothly over time according to specific rules. Third, when you measure a property like position or momentum, the wave function changes instantly to reflect the measurement outcome. Finally, before measurement, particles exist in a superposition of states, but measurements cause this superposition to "collapse" into a definite state. These postulates help us understand and predict behaviors at the smallest scales in nature.