Caption: Karl Schwarzschild (1873--1916) at work.

Schwarzschild is the discoverer of the famous Schwarzschild solution in general relativity.

The Schwarzschild solution is one of the few top-level (i.e., general and important) exact analytic solutions in general relativity. How many such solutions exist depends on one's definition of "exact analytic solution" and what one judges to be top-level. By one expert's count, there are only 6 top-level ones (see McCallum, 2013, Exact solutions of Einstein's equations) and he counts the Schwarzschild solution only as a special case of the Kerr solution.

As far as I know, Albert Einstein (1879--1955) himself only ever found only one exact analytic solution (the Einstein universe) and it is only a special case of one of the 6 general solutions: i.e., the Friedmann-Lemaitre-Robertson-Walker (FLRW) solution.

Schwarzschild found his eponymous exact analytic solution while serving in the Imperial German Army in 1915 at the Russian front. He was soon invalided out of active duty by a rare autoimmune disease and died in 1916. Schwarzschild was such a brilliant general relativist that it plausible to think that he would have anticipated some of the general-relativity results of others if he had lived longer: e.g., some of the early cosmological models like the Friedmann-Lemaitre-Robertson-Walker (FLRW) models.

Credit/Permission: Anonymous photographer, early 20th century (uploaded to Wikimedia Commons by User:KasugaHuang, 2006) / Public domain.
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