Weak homotopy-equivalent topological spaces: Difference between revisions
(Created page with "{{topospace eqrel}} ==Definition== Two topological spaces <math>X_1</math> and <math>X_2</math>are said to be '''weak homotopy-equivalent''' or '''weakly homotopy-equivalen...") |
|||
| (One intermediate revision by the same user not shown) | |||
| Line 29: | Line 29: | ||
| [[Stronger than::homology-equivalent topological spaces]] || generated by back and forth [[homology equivalence of topological spaces|homology equivalences]] || || [[homology-equivalent not implies weak homotopy-equivalent]] || | | [[Stronger than::homology-equivalent topological spaces]] || generated by back and forth [[homology equivalence of topological spaces|homology equivalences]] || || [[homology-equivalent not implies weak homotopy-equivalent]] || | ||
|- | |- | ||
| Spaces that have isomorphic [[homology group]]s || || || [[isomorphic homology groups not implies weak homotopy-equivalent]] || | | Spaces that have isomorphic [[homology group]]s ''and'' isomorphic [[fundamental group]]s and [[set of path components]] || || || [[isomorphic homology groups and isomorphic fundamental groups not implies weak homotopy-equivalent]] || | ||
|} | |} | ||
Latest revision as of 15:10, 29 July 2011
Definition
Two topological spaces and are said to be weak homotopy-equivalent or weakly homotopy-equivalent if the following is true:
We can find a collection of topological spaces and a collection of continuous maps , such that each is a map either from to or a map from to , and further, each is a weak homotopy equivalence of topological spaces.
Relation with other equivalence relations
Stronger equivalence relations
| Equivalence relation | Meaning | Proof of implication | Proof of strictness (reverse implication failure) | Intermediate notions |
|---|---|---|---|---|
| homeomorphic spaces | there is a bijective homeomorphism between the spaces | |||
| homotopy-equivalent topological spaces | there is a homotopy equivalence of topological spaces between the spaces | homotopy-equivalent not implies weak homotopy-equivalent |
Weaker equivalence relations
| Equivalence relation | Meaning | Proof of implication | Proof of strictness (reverse implication failure) | Intermediate notions |
|---|---|---|---|---|
| Spaces that have isomorphic homotopy groups | isomorphic homotopy groups not implies weak homotopy-equivalent | |||
| homology-equivalent topological spaces | generated by back and forth homology equivalences | homology-equivalent not implies weak homotopy-equivalent | ||
| Spaces that have isomorphic homology groups and isomorphic fundamental groups and set of path components | isomorphic homology groups and isomorphic fundamental groups not implies weak homotopy-equivalent |