Frobenius--Witt cotangent complexes
Abstract
We introduce the notion of the Frobenius--Witt cotangent complex, which can be considered as a derived variant of the module of Frobenius--Witt differentials defined by T. Saito. This new object also can be seen as an arithmetic variant of the notion of cotangent complex. We explain the suitability of these two viewpoints through a series of propositions. Furthermore, we establish a relationship between Frobenius--Witt cotangent complexes and the regularity of noetherian local rings, which can be considered as a derived variant of Saito's regularity criterion. This proof relies heavily on computations of Frobenius--Witt cotangent complexes in the case of perfectoid rings. We also study the deformation theory of delta structures using Frobenius--Witt cotangent complexes.
Related
- Frobenius--Witt cotangent complex for derived rings
- Quillen's finiteness conjecture for the cotangent complex in characteristic two
- Hermitian K-theory for stable ∞-categories III: Grothendieck--Witt groups of rings
- Magnetic cotangent groupoids
- Abundance of affine algebraic structures on stabilized cotangent bundles of surfaces
BibTeX
@misc{shimada2026frobeniuswitt,
title = {{Frobenius--Witt cotangent complexes}},
author = {Kanau Shimada},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2605.14803},
eprint = {2605.14803},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.14803},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Frobenius--Witt cotangent complexes
AU - Kanau Shimada
PY - 2026
DA - 2026/11/03
PB - arXiv
DO - 10.48550/arxiv.2605.14803
UR - https://arxiv.org/abs/2605.14803
AB - We introduce the notion of the Frobenius--Witt cotangent complex, which can be considered as a derived variant of the module of Frobenius--Witt differentials defined by T. Saito. This new object also can be seen as an arithmetic variant of the notion of cotangent complex. We explain the suitability of these two viewpoints through a series of propositions. Furthermore, we establish a relationship between Frobenius--Witt cotangent complexes and the regularity of noetherian local rings, which can be considered as a derived variant of Saito's regularity criterion. This proof relies heavily on computations of Frobenius--Witt cotangent complexes in the case of perfectoid rings. We also study the deformation theory of delta structures using Frobenius--Witt cotangent complexes.
ER -