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We give a detailed proof that locally Noetherian moduli stacks of sections carry canonical obstruction theories. As part of the argument, we construct a dualising sheaf and trace map, in the lisse-étale topology, for families of tame twisted curves when the base stack is locally Noetherian.
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This content will become publicly available on February 14, 2026
Topological rigidity in twisted, elastic ribbons
Topology is an important determinant of the behavior of a great number of condensed-matter systems, but until recently has played a minor role in elasticity. We develop a theory for the deformations of a class of twisted non-Euclidean sheets which have a symmetry based on the celebrated Bonnet isometry. We show that non-orientability is an obstruction to realizing the symmetry globally, and induces a geometric phase that captures a memory analogous to a previously identified one in 2D metamaterials. However, we show that orientable ribbons can also obstruct realizing the symmetry globally. This new obstruction is mediated by how the unit normal vector winds around the centerline of the ribbon, and provides conditions for constructing soft modes of deformation compatible with the topology of multiply-twisted connected ribbons.
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- Award ID(s):
- 2247095
- PAR ID:
- 10631186
- Publisher / Repository:
- arXiv
- Date Published:
- Page Range / eLocation ID:
- arXiv:2502.10593
- Format(s):
- Medium: X Other: pdf
- Institution:
- Syracuse University
- Sponsoring Org:
- National Science Foundation
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