What is quantum mechanics?

Quantum mechanics is a fundamental branch of physics that describes the behavior of matter and energy at the smallest scales, such as atoms, electrons, and photons. Unlike classical physics, which works well for everyday objects, quantum mechanics explains phenomena that occur at the microscopic level where particles exhibit both wave-like and particle-like properties. This dual nature leads to unique effects that classical theories cannot account for. At its core, quantum mechanics introduces concepts such as quantization of energy, wave-particle duality, superposition (where particles can exist in multiple states simultaneously), and entanglement (a connection between particles that allows their states to be correlated instantaneously over large distances). The theory is mathematically formulated using wave functions and operators, which predict the probabilities of finding a particle in a particular state rather than definite outcomes. Quantum mechanics is the foundation for much of modern physics and technology, underpinning the understanding of chemical reactions, semiconductors, lasers, and quantum computing. It fundamentally changed our view of the physical world by showing that at the microscopic level, nature is inherently probabilistic rather than deterministic.