How Math Works
Analysis & CalculusGeometry

Bernhard Riemann

1826 – 1866 · Germany

The man who defined area as 'the sum of thin rectangles'

Bernhard Riemann was a German mathematician who, in a short life, reshaped several branches of mathematics at the root. He defined the area under a curve rigorously as the limit of a sum of thin rectangles (the Riemann integral), giving integration a solid foundation. The 'Riemann hypothesis' he left behind remains the greatest unsolved problem in mathematics.

Key contributions

  • Gave integration a rigorous definition via the Riemann integral
  • The geometry of curved space (Riemannian geometry)
  • The Riemann hypothesis

Related concepts

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