I had intended to write a treatise describing the history of the hydrogen atom over the last 100 years. Unfortunately, my time is running out this year, so I will content myself instead with this much briefer blog post outlining the major events associated with Niels Bohr's three epochal papers in 1913. The hydrogen atom has been the most fundamental application at each level in the advancement of quantum theory. It is the only real physical system that can be solved exactly (although some might argue that this is also true for the radiation field, as an assembly of harmonic oscillators).
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