Conservation of energy

:This article is about the physics principle. For information on using energy resources sustainably, see Energy Conservation.

Modern physics

With the discovery of special relativity by Albert Einstein, mass and energy were shown to be interchangeable by the famous equation E = mc2. As a result, the rule of conservation of energy was shown to be a special case of a more general rule, the conservation of mass and energy, which is now usually just referred to as conservation of energy.

Related Topics:
Special relativity - Albert Einstein - Equation

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Conservation of energy can be shown through Noether's theorem to be the result of the time-invariance of the laws of physics (=time has no effect on any physical process).

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Within the realm of quantum mechanics, conservation of energy is not applicable when energy can not be defined (say, for time scales shorter than the uncertainty principle defines).

Related Topics:
Quantum mechanics - Uncertainty principle

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