Many mathematicians, including some of the most famous, produced nothing innovative past the age of 45 or 50. Isaac Newton (1642‒1727) is one example: after the belated publication of his Philosophiae naturalis principia mathematica, he took up duties as a Member of Parliament, then sank into depression, before turning to various pursuits far removed from the exact sciences.
Math after 40?
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So one may well wonder about the capacity for mathematical discovery beyond a certain age. Can important mathematical results still be produced after 40? The answer is yes: many scholars have pursued fruitful mathematical research very late in life. Here are a few instructive examples.
