Quantum

In physics, the term refers to quantum ( quantum of latin, how big ',' how much ') an object that is created with discrete values ​​of a physical quantity, usually energy, by a change of state in a system.

Quanta can always occur only in certain portions of this physical size, they are therefore the quantization of these variables.

Quantized values ​​are described in the framework of quantum mechanics and it inspired branches of theoretical physics such as quantum electrodynamics.

Examples

• The photon as a quantum of the electromagnetic field. Photons can indeed have different discrete energy levels, but are created or destroyed as a whole.
• The phonon as quantum mechanical distortion waves in the solid.
• The plasmon as quantum excitation in the solid state, in which the charge carriers vibrate against each other.
• The Magnon as quantum magnetic excitations.
• The quantum of angular momentum, which is not interpreted as a particle.
• The gluon as quantum of the force field, which transmits the strong interactions.
• The Graviton as size quantization of the gravitational field.

The term quantum

Often a particle character of the observed variable is associated with the physical concept Quant. However, this is only part of the actual meaning of the term. An example of a quantum, which one can ascribe no particle character, is the angular momentum quantum.

As a physical term quantum is not used to describe the atomic structure of matter, although even here a smallest unit of measure ( quantization ) occurs.