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Ideal Perturbation Lemma

Martin Markl
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Abstract

We explain the essence of perturbation problems. The key to understanding is the structure of chain homotopy equivalence -- the standard one must be replaced by a finer notion which we call a strong chain homotopy equivalence. We prove an Ideal Perturbation Lemma and show how both new and classical results follow from this ideal statement.

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Martin Markl. 2000-05-26. Ideal Perturbation Lemma. https://arxiv.org/abs/math/0002130

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