- Tombstone (typography)
The tombstone, halmos, or end of proof mark "Unicode|□" is used in
mathematics to denote the end of a proof, in place of the traditional abbreviation "QED" for the Latin phrase "quod erat demonstrandum" (Q.E.D.)., it is represented as character U+220E "End of Proof". Its graphic form varies. It may be a hollow or filled rectangle or square.
In
AMS-LaTeX , the symbol is automatically appended at the end of a proof environment egin{proof} ... end{proof}. It can also be obtained from the commands qedsymbol or qed (the latter causes the symbol to be right aligned).It is sometimes called a halmos after its
eponym Paul Halmos , who first used it in mathematical context, after seeing it was being used to indicate the end of articles inmagazine s. ["The symbol is definitely not my invention — it appeared in popular magazines (not mathematical ones) before I adopted it, but, once again, I seem to have introduced it into mathematics. It is the symbol that sometimes looks like [an empty square] , and is used to indicate an end, usually the end of a proof. It is most frequently called the 'tombstone', but at least one generous author referred to it as the 'halmos'.", Paul R. Halmos, "I Want to Be a Mathematician: An Automathography", 1985, p. 403, quoted at http://members.aol.com/jeff570/set.html.]Notes
ee also
*
Q.E.D.
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