An Introduction to Pull-backs of Bundles and Homotopy Invariance
نویسنده
چکیده
We define the pull-back of a smooth principal fibre bundle, and show that it has a natural principal fibre bundle structure. Next, we analyse the relationship between pull-backs by homotopy equivalent maps. The main result of this article is to show that for a principal fibre bundle over a paracompact manifold, there is a principal fibre bundle isomorphism between pull-backs obtained from homotopic maps. This enables simple proofs of several results on the structure of principal fibre bundles. No new results are obtained—this is simply an accessible presentation of an important idea.
منابع مشابه
Pull-backs of Bundles and Homotopy Invariance
We define the pull-back of a smooth principal fibre bundle, and show that it has a natural principal fibre bundle structure. Next, we analyse the relationship between pull-backs by homotopy equivalent maps. The main result of this article is to show that for a principal fibre bundle over paracompact manifolds, there is a principal fibre bundle isomorphism between pull-backs obtained from homoto...
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