Rational Spaces
A rational space is a simply connected space all of whose homotopy groups are vector spaces over the rational numbers. If X is any simply connected CW complex, then there is a rational space Y, unique up to homotopy equivalence, and a map from X to Y inducing an isomorphism on homotopy groups tensored with the rational numbers. The space Y is called the rationalization of X, and is the localization of X at the rationals, and is the rational homotopy type of X. Informally, it is obtained from X by killing all torsion in the homotopy groups of X.
Read more about this topic: Rational Homotopy Theory
Famous quotes containing the words rational and/or spaces:
“Every rational creature has all nature for his dowry and estate. It is his, if he will. He may divest himself of it; he may creep into a corner, and abdicate his kingdom, as most men do, but he is entitled to the world by his constitution.”
—Ralph Waldo Emerson (18031882)
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