Henri Poincaré

Émile Borel and the Infinite Monkey Problem

7. January 2023 Harald Sack

On January 7, 1871, French mathematician Félix Édouard Justin Émile Borel was born. Borel is known for his founding work in the areas of measure theory and probability. In one of his books on probability, he proposed the thought experiment that a monkey hitting keys at random on a typewriter keyboard will – with absolute certainty – eventually type every book in France’s Bibliothèque nationale de France (National Library). This is now…

mathematics

Gösta Mittag-Leffler and the Acta Mathematica

16. March 2022 Harald Sack

On March 16, 1846, Swedish mathematician Gösta Mittag-Leffler was born. Mittag-Leffler‘s contributions are connected chiefly with the theory of functions. His mathematical research helped advance the Scandinavian school of mathematics. He is probably best known for founding the international mathematical journal Acta Mathematica. “The mathematician’s best work is art, a high perfect art, as daring as the most secret dreams of imagination, clear and limpid. Mathematical genius and artistic genius touch one…

physics

Karl Schwarzschild and the Event Horizon

9. October 2021 Tabea Tietz

On October 9, 1873, German physicist and astronomer Karl Schwarzschild was born. He provided the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished in 1915, the same year that Albert Einstein first introduced general relativity. The Schwarzschild solution leads to a derivation of the Schwarzschild radius, which is the size of the event horizon of a…

mathematics

Henri Poincaré – the Last Universalist of Mathematics

29. April 2020 Tabea Tietz

On April 29, 1854, French mathematician, theoretical physicist, engineer, and a philosopher of science Henri Poincaré was born. He is often described as a polymath, and in mathematics as The Last Universalist since he excelled in all fields of the discipline as it existed during his lifetime. “A scientist worthy of the name, above all a mathematician, experiences in his work the same impression as an artist; his pleasure is as great…

mathematics

David Hilbert’s 23 Fundamental Problems

8. August 2019 Harald Sack

On August 8, 1900 David Hilbert, probably the greatest mathematician of his age, gave a speech at the Paris conference of the International Congress of Mathematicians, at the Sorbonne, where he presented 10 mathematical Problems (out of a list of 23), all unsolved at the time, and several of them were very influential for 20th century mathematics. “Who of us would not be glad to lift the veil behind which the future…

physics

The Annus Mirabilis in Physics – Albert Einstein and the Year 1905

30. June 2018 Harald Sack

Have you ever heard of the “Annus Mirabilis” (in German “Wunderjahr“) of physics? 1905 was this Annus Mirabilis, this year of wonders or extraordinary year. History considers 1905 as the year with the most outstanding and influential papers ever published by famous physicist Albert Einstein in the the Annalen der Physik scientific journal. These four articles contributed substantially to the foundation of modern physics and changed views on space, time, and matter.…

mathematics

George David Birkhoff and the Ergodic Theorem

21. March 2017 Harald Sack

On March 21, 1884, American mathematician George David Birkhoff was born. Birkhoff is best known for what is now called the ergodic theorem. Birkhoff was one of the most important leaders in American mathematics in his generation, and during his time he was considered by many to be the preeminent American mathematician. “The transcendent importance of love and good-will in all human relationships is shown by their mighty beneficent effect upon the…