Quantum physics, also known as quantum mechanics or quantum theory, is the fundamental branch of physics that describes the behavior and interactions of matter and energy at the smallest scales-specifically at the atomic and subatomic levels, including particles such as electrons, photons, protons, and quarks
. Key aspects of quantum physics include:
- Wave-Particle Duality: Quantum objects like electrons and light exhibit both particle-like and wave-like properties depending on the experimental context
- Probabilistic Nature: Unlike classical physics, quantum mechanics does not predict exact outcomes but rather probabilities of where particles might be found or how they behave. This is mathematically represented by a wave function and the Born rule, which calculates probabilities from complex amplitudes
- Uncertainty Principle: It is impossible to simultaneously measure certain pairs of properties (such as position and velocity) with arbitrary precision
- Entanglement: Particles that have interacted can exhibit correlated properties even when separated by large distances, a phenomenon that defies classical intuition
Quantum physics underpins our understanding of how atoms and molecules work, influencing chemistry, biology, and technology. It explains phenomena such as electron behavior in semiconductors, light-matter interactions in lasers, and energy production in the sun
. Although quantum effects are most evident at microscopic scales, they fundamentally govern all matter and energy. Developed in the early 20th century to resolve inconsistencies classical physics could not explain, quantum mechanics has been experimentally verified to extremely high precision and forms the basis for modern technologies like quantum computing, quantum cryptography, and advanced imaging
. In summary, quantum physics is the theory that describes the fundamental nature and behavior of the smallest building blocks of the universe, revealing a world that is probabilistic, interconnected, and fundamentally different from everyday classical experience.
