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arXiv · 1402.6250

The almost periodic rigidity of crystallographic bar-joint frameworks

G. Badri·D. Kitson·S. C. Power
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Abstract

A crystallographic bar-joint framework C is shown to be almost periodically infinitesimally rigid if and only if it is strictly periodically infinitesimally rigid and the rigid unit mode (RUM) spectrum is a singleton. Moreover the almost periodic infinitesimal flexes of C are characterised in terms of a matrix-valued function on the d-torus determined by a full rank translation symmetry group and an associated motif of joints and bars.

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G. Badri, D. Kitson, S. C. Power. 2014-02-25. The almost periodic rigidity of crystallographic bar-joint frameworks. https://arxiv.org/abs/1402.6250

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