Elements
Explicitly, the binary tetrahedral group is given as the group of units in the ring of Hurwitz integers. There are 24 such units given by
with all possible sign combinations.
All 24 units have absolute value 1 and therefore lie in the unit quaternion group Sp(1). The convex hull of these 24 elements in 4-dimensional space form a convex regular 4-polytope called the 24-cell.
Read more about this topic: Binary Tetrahedral Group
Famous quotes containing the word elements:
“It is a life-and-death conflict between all those grand, universal, man-respecting principles which we call by the comprehensive term democracy, and all those partial, person-respecting, class-favoring elements which we group together under that silver-slippered word aristocracy. If this war does not mean that, it means nothing.”
—Antoinette Brown Blackwell (1825–1921)
“Nature confounds her summer distinctions at this season. The heavens seem to be nearer the earth. The elements are less reserved and distinct. Water turns to ice, rain to snow. The day is but a Scandinavian night. The winter is an arctic summer.”
—Henry David Thoreau (1817–1862)
“An illustrious individual remarks that Mrs. [Elizabeth Cady] Stanton is the salt, Anna Dickinson the pepper, and Miss [Susan B.] Anthony the vinegar of the Female Suffrage movement. The very elements get the “white male” into a nice pickle.”
—Anonymous, U.S. women’s magazine contributor. The Revolution (August 19, 1869)