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For my level of understanding the only explanation of mass to energy, ie nuclear weaponry, is limited to a simple summing game where a mass deficit is expressed as energy. For the 'reverse' process, ie in the LHC at CERN, it is a similar story, energy in, mass out.

Is there a more detailed physical explanation of what is occuring and if so is it mirrored by the two processes?

(Obviously pure physical theory at some level is just numbers in, numbers out but that alone doesn't preclude the possibility of some physical description between high level text book and base theory.)

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Related: – Qmechanic Feb 14 '12 at 15:52

There is no such thing as an energy-to-mass-process, nor the other way around. There are only processes in which energy/mass is converted from one particle / collection thereof to another one, each in states with the same total energy/mass. For instance, in nuclear decay, the original nucleus had the same total mass and energy as the resulting particles' (relativistic) mass/energy. In a particle accelerator, the electric fields used to speed up the particles can be seen as photons, which together have relativistic mass equal to the kinetic energy the accelerated particles gain.

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The mass energy equivalence cannot be understood by handwaving arguments . One has to read about special relativity and how mass and energy are equivalent, measured in the same units. Transmutations of mass to energy and energy to mass is governed by conservation rules, both of energy,momentum and quantum numbers. Have a start with the wiki article on special relativity.

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Hah,yeah. I do have a masters degree in astrophysics by the way ;-) – Nic Feb 14 '12 at 22:09
What was the purpose of the question, then? Once one knows about four dimensional vectors and special relativity the physics is clear. – anna v Feb 15 '12 at 5:17

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