Template:Selected anniversaries/April 20

From Gnomon Chronicles
Jump to navigation Jump to search
  • 1548: Mathematician, astronomer, and alleged time-traveller Petrus Apianus publishes Cosmographicus furatis, his magisterial treatise on crimes against astronomical constants.

    1548: Mathematician, astronomer, and alleged time-traveller Petrus Apianus publishes Cosmographicus furatis, his magisterial treatise on crimes against astronomical constants.

  • 1653: Oliver Cromwell dissolves the Rump Parliament.

    1653: Oliver Cromwell dissolves the Rump Parliament.

  • 1790: Mathematician and detective Johann Friedrich Pfaff uses partial differential equations of the first order Pfaffian systems to track and erase the Forbidden Ratio.

    1790: Mathematician and detective Johann Friedrich Pfaff uses partial differential equations of the first order Pfaffian systems to track and erase the Forbidden Ratio.

  • 1902: Pierre and Marie Curie refine radium chloride.

    1902: Pierre and Marie Curie refine radium chloride.

  • 1932: Mathematician Giuseppe Peano dies. He did pioneering work in mathematical logic and set theory.

    1932: Mathematician Giuseppe Peano dies. He did pioneering work in mathematical logic and set theory.

  • Mathematician Georg Feigl dies. He worked on the foundations of geometry and topology, studying fixed point theorems for n-dimensional manifolds. Feigl was one of the initial authors of the Mathematisches Wörterbuch ("Mathematical dictionary").

    Mathematician Georg Feigl dies. He worked on the foundations of geometry and topology, studying fixed point theorems for n-dimensional manifolds. Feigl was one of the initial authors of the Mathematisches Wörterbuch ("Mathematical dictionary").

  • 1961: Failure of the Bay of Pigs Invasion of US-backed Cuban exiles against Cuba.

    1961: Failure of the Bay of Pigs Invasion of US-backed Cuban exiles against Cuba.

Retrieved from "https://gnomonchronicles.com/w/index.php?title=Template:Selected_anniversaries/April_20&oldid=31094"