The term “QED” is actually an abbreviation and stands for the Latin quod erat demonstrandum, meaning “which was to be demonstrated.”

QED typically is used to signify the end of a mathematical proof. The symbol

is often used in place of “QED,” and is called the “tombstone”, “Halmos symbol” or “Halmos tombstone” after mathematician Paul Halmos (it can vary in width, however, and sometimes it is fully or partially shaded). Halmos borrowed this symbol from magazines, where it was used to denote “end of article”.

Title QED
Canonical name QED
Date of creation 2013-03-22 12:40:14
Last modified on 2013-03-22 12:40:14
Owner mathwizard (128)
Last modified by mathwizard (128)
Numerical id 8
Author mathwizard (128)
Entry type Definition
Classification msc 00A99
Synonym Q.E.D
Related topic QEDInTheoreticalAndMathematicalPhysics
Related topic QCDOrQuantumChromodynamics
Related topic MathematicalFoundationsOfQuantumFieldTheories
Related topic QuantumOperatorAlgebrasInQuantumFieldTheories
Related topic GrassmanHopfAlgebrasAndTheirDualCoAlgebras
Related topic FoundationsOfQuantumFieldTheories
Related topic QuantumChromod
Defines Halmos symbol
Defines tombstone
Defines Halmos tombstone