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:
“Every philosophy is tinged with the colouring of some secret imaginative background, which never emerges explicitly into its train of reasoning.”
—Alfred North Whitehead (1861–1947)
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—Newt Gingrich (b. 1943)