Moore space (algebraic topology)

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See also Moore space for other meanings in mathematics.

In algebraic topology, a branch of mathematics, Moore space is the name given to a particular type of topological space that is the homology analogue of the Eilenberg-Maclane spaces of homotopy theory.

[edit] Formal definition

Given an abelian group G and an integer n ≥ 1, let X be a CW complex such that

$H_n(X) \cong G$

and

$\tilde{H}_i(X) \cong 0$

for i ≠ n, where H_n(X) denotes the n-th singular homology group of X and $\tilde{H}_i(X)$ is the ith reduced homology group. Then X is said to be a Moore space.

[edit] Examples

$S n$ is a Moore space of $\mathbb{Z}$ for $n\geq 1$ .

$\mathbb{RP}^2$ is a Moore space of $\mathbb{Z}/2\mathbb{Z}$ (n=1).

[edit] References

Hatcher, Allen. Algebraic topology, Cambridge University Press (2002), ISBN 0-521-79540-0. For further discussion of Moore spaces, see Chapter 2, Example 2.40. A free electronic version of this book is available on the author's homepage.