Conservation law

In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves. Any particular conservation law is a mathematical identity to certain symmetry of a physical system. A partial listing of conservation laws that are said to be exact laws, or more precisely have never been shown to be violated:
 * Conservation of energy
 * Conservation of linear momentum
 * Conservation of angular momentum
 * Conservation of electric charge
 * Conservation of color charge
 * Conservation of weak isospin
 * Conservation of probability

There are also approximate conservation laws. These are approximately true in particular situations, such as low speeds, short time scales, or certain interactions.


 * Conservation of mass (applies for low speeds)
 * Conservation of baryon number (See chiral anomaly)
 * Conservation of lepton number (In the Standard Model)
 * Conservation of flavor (violated by the weak interaction)
 * Conservation of parity
 * CP symmetry