Hendrik Lorentz wrote the equations of relativity before Einstein explained them
The mathematics at the heart of special relativity carries the name of a Dutch physicist, Hendrik Lorentz. Working to rescue the idea of a light-carrying aether, he introduced a local time for moving observers, shrinking lengths and slowed clocks. Henri Poincaré named the resulting formulas the Lorentz transformations in 1905.
Lorentz was born in Arnhem in 1853 and excelled at school in science and mathematics as well as English, French and German. At Leiden an astronomy professor, Frederik Kaiser, drew him to physics. While teaching night school back in Arnhem he kept studying, and his 1875 doctoral thesis refined Maxwell's electromagnetic theory of light. In 1878, still in his mid-twenties, he took Leiden's new chair of theoretical physics, which had first been offered to Johannes van der Waals.
In the 1890s he tackled how light behaves in frames moving through the supposed aether. He found the maths simplified if each location used its own local time, which Poincaré later called his most ingenious idea. To account for the Michelson-Morley experiment's failure to detect aether drift, he proposed in 1892 that moving bodies contract along their direction of travel, and by 1904 had added time dilation. Joseph Larmor had apparently used the same transformations in 1897 without Lorentz knowing, and all of these are algebraically equivalent to the versions Poincaré and Einstein published in 1905.
In 1902 he and Pieter Zeeman split the physics Nobel for revealing and accounting for how magnetic fields split spectral lines. The Lorentz force, describing how electric and magnetic fields push on a charged particle, is another of his contributions, along with an oscillator model for how materials bend light near their resonant frequencies.
By 1910 teaching and administration were crowding out his research. He asked Einstein to succeed him, but Einstein, newly settled in Zurich, was daunted by the prospect of filling his shoes, and Paul Ehrenfest got the chair. Lorentz moved to Teylers Museum in Haarlem in 1912 while giving famous Monday morning lectures at Leiden. From 1925 until his death in 1928 he chaired the international committee that preceded UNESCO.
Source: Hendrik Lorentz
