In fact, the first law of conservation (that of mass) was found in chemistry
and generalized to the conservation of energy in physics by means of Einstein’s
famous “E=mc2”. Energy conservation is implied by the principle of least
action from a...
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In fact, the first law of conservation (that of mass) was found in chemistry
and generalized to the conservation of energy in physics by means of Einstein’s
famous “E=mc2”. Energy conservation is implied by the principle of least
action from a variational viewpoint as in Emmy Noether’s theorems (1918): any
chemical change in a conservative (i.e. “closed”) system can be accomplished only
in the way conserving its total energy. Bohr’s innovation to found Mendeleev’s
periodic table by quantum mechanics implies a certain generalization referring to
the quantum leaps as if accomplished in all possible trajectories (according to Feynman’s
interpretation) and therefore generalizing the principle of least action and
needing a certain generalization of energy conservation as to any quantum change.
The transition from the first to the second theorem of Emmy Noether represents
well the necessary generalization: its chemical meaning is the generalization of any
chemical reaction to be
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