Whitehead Group

Whitehead group in mathematics may mean:

  • A group W with Ext(W, Z)=0; see Whitehead problem
  • For a ring, the Whitehead group Wh(A) of a ring A, equal to
  • For a group, the Whitehead group Wh(G) of a group G, equal to K1(Z)/{±G}. Note that this is a quotient of the Whitehead group of the group ring.
  • The Whitehead group Wh(A) of a simplicial complex or PL-manifold A, equal to Wh(π1(A)); see Whitehead torsion.

All named after J. H. C. Whitehead.

Famous quotes containing the words whitehead and/or group:

    If a dog jumps into your lap it is because he is fond of you; but if a cat does the same thing it is because your lap is warmer.
    —Alfred North Whitehead (1861–1947)

    The trouble with tea is that originally it was quite a good drink. So a group of the most eminent British scientists put their heads together, and made complicated biological experiments to find a way of spoiling it. To the eternal glory of British science their labour bore fruit.
    George Mikes (b. 1912)