What is the origin of quantum mechanics?

The origin of quantum mechanics is marked by its conceptual break from classical mechanics and the development of new mathematical frameworks to explain phenomena at the atomic and subatomic levels. Around the early 20th century, several key developments shaped quantum theory:

1. Planck's Quantum Hypothesis (1900): Max Planck proposed that energy is quantized, introducing the concept of quanta to explain black-body radiation.

2. Matrix Mechanics (1925): Werner Heisenberg formulated matrix mechanics, which was the first complete and consistent quantum theory.

3. Wave Mechanics (1926): Almost simultaneously, Erwin Schrödinger developed wave mechanics, which described the behavior of quantum systems with the Schrödinger equation.

4. Copenhagen Interpretation (1927): Niels Bohr and colleagues developed an interpretation of quantum mechanics that includes wave-particle duality and the principle of complementarity.

Initially, the models by Niels Bohr started with a classical-looking planetary atom model, which introduced quantum jumps marking early steps away from classical ideas. Luis de Broglie and later David Bohm contributed with theories like the pilot wave model, advancing the understanding of particle behavior. The quantum theories rapidly evolved during the 1920s, leading to new foundational principles distinctly different from those of classical physics, such as the superposition of states and the uncertainty principle. These developments culminated in a radical new theory that fundamentally changed our understanding of nature at microscopic scales, paving the way for further developments in physics and influencing numerous technological advances 1 2 3.