Johann Jakob Balmer

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Johann Jakob Balmer (May 1, 1825 – March 12, 1898) was a Swiss mathematician and an honorary physicist.

[edit] Life and work

He was born in Lausen, Switzerland, the son of a Chief Justice also named Johann Jakob Balmer. His mother was Elizabeth Rolle Balmer, and he was the oldest son. During his schooling he excelled in mathematics, and so decided to focus on that field when he attended university.

He studied at the University of Karlsruhe and the University of Berlin, then completed his Ph.D. from the University of Basel in 1849 with a dissertation on the cycloid. Johann then spent his entire life in Basel, where he taught at a school for girls. He also lectured at the University of Basel. In 1868 he married Christine Pauline Rinck at the age of 43. The couple had a total of six children.

Despite being a mathematician, he is not remembered for any work in that field; rather, his major contribution (made at the age of sixty, in 1885) was an empirical formula for the visible spectral lines of the hydrogen atom. Balmer's formula computed the wavelength as follows:

$\lambda\ = \frac{ hm^2 }{ m^2 - n^2 }$

for n = 2, h = 3.6546×10⁻⁷ m, and m = 3, 4, 5, 6, and so forth. Balmer then used this formula to predict the wavelength for m = 7, and a colleague at the university was able to confirm a match to a high degree of accuracy. See Balmer series for further explanation of this relationship.

Balmer's formula was later found to be a special case of a more general formula, by Johannes Rydberg. A full explanation of why these formulas worked, however, had to wait until the presentation of the Bohr model of the atom by Niels Bohr in 1913.

Johann Balmer died in Basel.