The rest energy of a particle is defined as:
- ,
where is the speed of light in a vacuum. In general, only differences in energy have physical significance.
The concept of rest energy follows from the Special theory of relativity that leads to Einstein's famous conclusion about equivalence of energy and mass. See background for mass-energy equivalence.
On the other hand, the concept of the equivalent Dirac invariant rest mass may be defined in terms of the self energy corresponding to the product of a geometric matter current and a generalized potential as part of a single definition of mass in a geometric unified theory.
Read more about this topic: Invariant Mass
Famous quotes containing the words rest and/or energy:
“... the trouble is that most people in this country think that we can stay out of wars in other parts of the world. Even if we stay out of it and save our own skins, we cannot escape the conditions which will undoubtedly exist in other parts of the world and which will react against us.... We are all of us selfish ... and if we can save our own skins, the rest of the world can go. The best we can do is to realize nobody can save his own skin alone. We must all hang together.”
—Eleanor Roosevelt (1884–1962)
“Reckoned physiologically, everything ugly weakens and afflicts man. It recalls decay, danger, impotence; he actually suffers a loss of energy in its presence. The effect of the ugly can be measured with a dynamometer. Whenever man feels in any way depressed, he senses the proximity of something “ugly.” His feeling of power, his will to power, his courage, his pride—they decline with the ugly, they increase with the beautiful.”
—Friedrich Nietzsche (1844–1900)