Operator Calculus of Differential Chains and Differential Forms

Jenny Harrison

Published 2012-10-16, updated 2015-11-10Version 2

Differential chains are a proper subspace of de Rham currents given as an inductive limit of Banach spaces endowed with a geometrically defined strong topology. Boundary is a continuous operator, as are operators that dualize to Hodge star, Lie derivative, pullback and interior product. Partitions of unity exist in this setting, as does Cartesian wedge product. Subspaces of finitely supported Dirac chains and polyhedral chains are both dense, leading to a unification of the discrete with the smooth continuum. We conclude with an application generalizing a simple version of the Reynolds' Transport Theorem to rough domains.