halmos
Noun
Meaning
halmos
(mathematics) The symbol “∎” marking the end of a proof.
Synonyms
Anagrams
Examples
Halmos rather confusingly uses the term "Borel set" for elements of the σ-ring generated by compact sets, and defines Haar measure on these sets.
Halmos 1974, p. 28, Ex. 9 Once a basis of V is chosen, linear maps f : V → W are completely determined by specifying the images of the basis vectors, because any element of V is expressed uniquely as a linear combination of them.
Halmos later stated that it was the fastest book he wrote, taking about six months, and that the book "wrote itself". citation.
Some of the ideas used in Halmos' proof reappeared many years later in Halmos' own work on quasi-triangular operators.
This was later called the tombstone or Halmos symbol by mathematicians.
Two famous papers are: citation. citation. citation Of the 1932 papers on ergodic theory, Paul Halmos writes that even "if von Neumann had never done anything else, they would have been sufficient to guarantee him mathematical immortality".