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Jan 5, 2022 at 12:10 answer added Johannes Huisman timeline score: 3
Jan 4, 2022 at 18:12 comment added Yu Li @Johannes Hahn: Since I want to find some other proofs of this.
Jan 4, 2022 at 17:39 history edited Yu Li CC BY-SA 4.0
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Jan 4, 2022 at 17:02 comment added Johannes Hahn Why would you want to prove a statement about localisations without using localisations?
Jan 4, 2022 at 16:54 comment added Fedor Petrov if $r\in R$, $r\ne 0$, and $r=\sum (a_ix_i-i)f_i$, simply put $x_i=1/a_i$ (and multiply by a product of $a_i$ to a large power, so that you deal only with polynomial identity) to get 0 in RHS
Jan 4, 2022 at 16:52 answer added Johannes Hahn timeline score: 2
Jan 4, 2022 at 16:49 comment added Yu Li @Uriya First: Yes, I exactly mean that, thank you. In fact, I'm thinking about the localization of a commutative ring and I found that one could construct $ S^{-1}R $ by taking $ R[S]/I $, where $ R[S] $ is the free commutative algebra over $ R $ generated by a multiplicatively closed subset $ S $ of $ R $ and $ I $ the ideal that contains $ s i(s)-1 $ for each $ s $ in $ S $, where $ i:S\to R[S] $ the canonical embedding. So I wonder that can we prove this proposition without using localization.
Jan 4, 2022 at 16:38 history edited Yu Li CC BY-SA 4.0
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Jan 4, 2022 at 15:36 comment added Uriya First I think your question is equivalent to whether $(a_1x_1-1,+\dots+,a_nx_n-1)\cap R=\{0\}$ (with $(a_1x_1-1,\dots,a_nx_n-1)$ denoting the ideal generated by $a_1x_1-1,\dots,a_nx_n-1$ in $R[x_1,\dots,x_n]$), am I right? This is true if $R$ is a field, and, by passing to the fraction field, also if $R$ is a domain.
Jan 4, 2022 at 14:44 comment added Andrea Ferretti It is bizarre indeed, also because the expression is generically nonzero. I think the question needs some rephrasing - as it is written, I cannot tell the correct form
Jan 4, 2022 at 14:39 comment added Gro-Tsen The statement “there's no nonzero $r$ such that $\operatorname{expression} =r$” where the expression does not depend on $r$, is bizarre: why not write $\operatorname{expression}=0$ then?
Jan 4, 2022 at 14:17 history edited YCor CC BY-SA 4.0
fixed typo
Jan 4, 2022 at 14:16 history edited Yu Li CC BY-SA 4.0
edited body
S Jan 4, 2022 at 14:04 review First questions
Jan 4, 2022 at 14:52
S Jan 4, 2022 at 14:04 history asked Yu Li CC BY-SA 4.0