| Title: | A note on certain Tannakian group schemes (English) | 
| Author: | Amrutiya, Sanjay | 
| Language: | English | 
| Journal: | Archivum Mathematicum | 
| ISSN: | 0044-8753 (print) | 
| ISSN: | 1212-5059 (online) | 
| Volume: | 56 | 
| Issue: | 1 | 
| Year: | 2020 | 
| Pages: | 21-29 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | In this note, we prove that the $F$-fundamental group scheme is a birational invariant for smooth projective varieties. We prove that the $F$-fundamental group scheme is naturally a quotient of the Nori fundamental group scheme. For elliptic curves, it turns out that the $F$-fundamental group scheme and the Nori fundamental group scheme coincide. We also consider an extension of the Nori fundamental group scheme in positive characteristic using semi-essentially finite vector bundles, and prove that in this way, we do not get a non-trivial extension of the Nori fundamental group scheme for elliptic curves, unlike in characteristic zero. (English) | 
| Keyword: | F-fundamental group scheme | 
| Keyword: | Frobenius-finite Vector bundles | 
| MSC: | 14F05 | 
| MSC: | 14L15 | 
| idZBL: | Zbl 07177877 | 
| idMR: | MR4075885 | 
| DOI: | 10.5817/AM2020-1-21 | 
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| Date available: | 2020-03-02T09:05:10Z | 
| Last updated: | 2020-08-26 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/148033 | 
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