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arXiv · 1002.4143

De Rham Theorem for L^\infty forms and homology on singular spaces

L. Shartser·G. Valette
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Abstract

We introduce smooth L^\infty differential forms on a singular (semialgebraic) set X in R^n. Roughly speaking, a smooth L^\infty differential form is a certain class of equivalence of 'stratified forms', that is, a collection of smooth forms on disjoint smooth subsets (stratification) of X with matching tangential components on the adjacent strata and bounded size (in the metric induced from R^n). We identify the singular homology of X as the homology of the chain complex generated by semialgebraic singular simplices, i.e. continuous semialgebraic maps from the standard simplices into X. Singular cohomology of X is defined as the homology of the Hom dual to the chain complex of the singular chains. Finally, we prove a De Rham type theorem establishing a natural isomorphism between the singular cohomology and the cohomology of smooth L^\infty forms.

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L. Shartser, G. Valette. 2010-02-22. De Rham Theorem for L^\infty forms and homology on singular spaces. https://arxiv.org/abs/1002.4143

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