# Quantum Physics

A Quantum Physics is a Physics of the small scales and low energy levels of atoms and subatomic particles.

**AKA:**Quantum Mechanics.**See:**Electron Microscope, Quantum Field Theory, Quantum State, Quantum Object, Subatomic Particle, Classical Physics, Quantization (Physics), Particle, Wave, Wave-Particle Duality, Uncertainty Principle, History of Quantum Mechanics, Quantum Entanglement.

## References

### 2017

- (Wikipedia, 2017) ⇒ https://en.wikipedia.org/wiki/Quantum_mechanics Retrieved:2017-6-8.
**Quantum mechanics**(**QM**; also known as quantum physics**or**quantum theory**), including quantum field theory, is a branch of physics which is the fundamental theory of nature at small scales and low energy levels of atoms and subatomic particles. Classical physics, the physics existing before quantum mechanics, derives from quantum mechanics as an approximation valid only at large (macroscopic) scales. Quantum mechanics differs from classical physics in that energy, momentum and other quantities are often restricted to discrete values (quantization), objects have characteristics of both particles and waves (wave-particle duality), and there are limits to the precision with which quantities can be known (uncertainty principle).**Quantum mechanics gradually arose from Max Planck's solution in 1900 to the black-body radiation problem (reported 1859) and Albert Einstein's 1905 paper which offered a quantum-based theory to explain the photoelectric effect (reported 1887). Early quantum theory was profoundly reconceived in the mid-1920s.

The reconceived theory is formulated in various specially developed mathematical formalisms. In one of them, a mathematical function, the wave function, provides information about the probability amplitude of position, momentum, and other physical properties of a particle.

**Important applications of quantum theory include quantum chemistry, superconducting magnets, light-emitting diodes, and the laser, the transistor and semiconductors such as the microprocessor, medical and research imaging such as magnetic resonance imaging and electron microscopy, and explanations for many biological and physical phenomena for energy .**