Physics

Quantum Physics

Quantum physics, also known as quantum mechanics, is a fundamental branch of physics that explores the behavior of matter and energy on the smallest scales—atoms and subatomic particles. Unlike classical physics, which governs macroscopic objects and is based on deterministic principles, quantum physics operates on probabilistic and often counterintuitive rules.

The Birth of Quantum Physics

Quantum physics emerged in the early 20th century to address phenomena that classical physics couldn't explain. Max Planck, in 1900, introduced the idea that energy is quantized, existing in discrete packets called "quanta." This idea resolved the ultraviolet catastrophe in blackbody radiation. Later, Albert Einstein's explanation of the photoelectric effect in 1905, showing that light also behaves as particles called photons, solidified the quantum perspective.

Key Principles of Quantum Physics

1. Wave-Particle Duality: Quantum entities, such as electrons and photons, exhibit both particle-like and wave-like properties. This duality is context-dependent, as shown by experiments like the double-slit experiment.

2. Superposition: Particles exist in a combination of all possible states until measured. For instance, an electron can be in multiple locations simultaneously. The act of measurement collapses this superposition into a single state.

3. Entanglement: When particles become entangled, their states are interconnected, regardless of the distance between them. A change in one particle instantaneously affects the other, challenging classical notions of locality.

4. Uncertainty Principle: Werner Heisenberg formulated that certain pairs of properties, such as position and momentum, cannot be simultaneously measured with perfect accuracy. This limitation is intrinsic to nature, not a result of measurement errors.