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arXiv · 1803.01463

Motivic cohomology of fat points in Milnor range

Jinhyun Park·Sinan Ünver
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Abstract

We introduce a new algebraic-cycle model for the motivic cohomology theory of truncated polynomials $k[t]/(t^m)$ in one variable. This approach uses ideas from the deformation theory and non-archimedean analysis, and is distinct from the approaches via cycles with modulus. We compute the groups in the Milnor range when the base field is of characteristic $0$, and prove that they give the Milnor $K$-groups of $k[t]/(t^m)$, whose relative part is the sum of the absolute K\"ahler differential forms.

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Jinhyun Park, Sinan Ünver. 2018-03-05. Motivic cohomology of fat points in Milnor range. https://arxiv.org/abs/1803.01463

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