The
law of conservation of mass states that the
mass of an isolated system will always remain constant, regardless of the processes acting inside the system. This law is
non-relativistic - the true (relativistic) situation is somewhat more complicated. The law was first formulated by
Antoine Lavoisier, who is often referred to as the father of modern
chemistry.
This law finds application as an approximation in cases where relativistic corrections are small - for example in chemistry.
See also conservation law, conservation of energy
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