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Q & A: Mass-energy equivalence

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Most recent answer: 10/28/2007
Q:
Assuming that e=mc˛, does this mean ultimately that all matter is made out of energy?

Thanks!
- john (age 39)
ireland
A:
You can consider energy as a Universal Currency, i.e. it can be traded among its various forms such as potential energy, kinetic energy, as well as matter.  So in that sense all matter is a form of energy; its trade-in value is mc˛.   There are trade restrictions however.  Most matter, such as a proton, does not spontaneously turn into energy.  A proton can annihilate, releasing energy, if it meets up with an anti-proton, but there are not many of those around. 

LeeH

(published on 10/28/2007)

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