Noether's normalization in skew polynomial rings

التفاصيل البيبلوغرافية
العنوان: Noether's normalization in skew polynomial rings
المؤلفون: Paran, Elad, Vo, Thieu N.
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Rings and Algebras
الوصف: We study Noether's normalization lemma for finitely generated algebras over a division algebra. In its classical form, the lemma states that if $I$ is a proper ideal of the ring $R=F[t_1,\ldots,t_n]$ of polynomials over a field $F$, then the quotient ring $R/I$ is a finite extension of a polynomial ring over $F$. We prove that the lemma holds when $R=D[t_1,\ldots,t_n]$ is the ring of polynomials in $n$ central variables over a division algebra $D$. We provide examples demonstrating that Noether's normalization may fail for the skew polynomial ring $D[t_1,\ldots,t_n;\sigma_1,\ldots,\sigma_n]$ with respect to commuting automorphisms $\sigma_1,\ldots,\sigma_n$ of $D$. We give a sufficient condition for $\sigma_1,\ldots,\sigma_n$ under which the normalization lemma holds for such ring. In the case where $D=F$ is a field, this sufficient condition is proved to be necessary.
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2407.12686
رقم الأكسشن: edsarx.2407.12686
قاعدة البيانات: arXiv