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Timeline for $K_1(k[x]/(x^2))$ for a field $k$

Current License: CC BY-SA 4.0

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Nov 17, 2022 at 13:08 comment added user443060 I wanted to post this as a separate question but in this thread if I get some hint it would be helpful. So $K_1(k[x]/(x^2))$ is properly understood. But if I extend it to $K_1((k[x]/(x^2))[y])$ will the result be same? Here I find the problem at $SK_1$.
Nov 7, 2022 at 4:48 comment added user443060 Thank you very much. I will read through it definitely.
Nov 6, 2022 at 18:32 comment added F Zaldivar For a commutative ring $A$, the determinant splits $K_1(A)\simeq A^{\times}\oplus (\text{SL}(A)/E(A)$, and the second summand is trivial when $\text{SL}(A)$ is generated by elementary matrices. This is the case when $A$ is a local ring, as in your example. I don't have Weibel's textbook, but probably this is discussed there since it is standard for an introduction to algebraic K-theory.
Nov 6, 2022 at 17:58 comment added Steven Landsburg @Mohan: I don't think we even need Artin for this.
Nov 6, 2022 at 17:40 comment added Mohan For any artin local ring, $K_1$ is just the group of units.
Nov 6, 2022 at 17:35 history edited YCor
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Nov 6, 2022 at 17:12 history edited LSpice CC BY-SA 4.0
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Nov 6, 2022 at 17:09 history asked user443060 CC BY-SA 4.0