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arXiv · 1806.04208

Big polynomial rings with imperfect coefficient fields

Daniel Erman·Steven V Sam·Andrew Snowden
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Abstract

We previously showed that the inverse limit of standard-graded polynomial rings with perfect coefficient field is a polynomial ring, in an uncountable number of variables. In this paper, we show that the same result holds with arbitrary coefficient field. We also prove an analogous result for ultraproducts of polynomial rings.

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Daniel Erman, Steven V Sam, Andrew Snowden. 2018-06-11. Big polynomial rings with imperfect coefficient fields. https://doi.org/10.1307/mmj/1603353740

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