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arXiv · 2312.11709

Extended Regge complex for linearized Riemann-Cartan geometry and cohomology

Snorre H. Christiansen·Kaibo Hu·Ting Lin
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Abstract

We show that the cohomology of the Regge complex in three dimensions is isomorphic to $\mathcal{H}^{{\scriptscriptstyle \bullet}}_{dR}(\Omega)\otimes\mathcal{RM}$, the infinitesimal-rigid-body-motion-valued de~Rham cohomology. Based on an observation that the twisted de~Rham complex extends the elasticity (Riemannian deformation) complex to the linearized version of coframes, connection 1-forms, curvature and Cartan's torsion, we construct a discrete version of linearized Riemann-Cartan geometry on any triangulation and determine its cohomology.

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Snorre H. Christiansen, Kaibo Hu, Ting Lin. 2023-12-18. Extended Regge complex for linearized Riemann-Cartan geometry and cohomology. https://arxiv.org/abs/2312.11709

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