We define the algebraic fundamental group π 1(G) of a reductive group scheme G over an arbitrary non-empty base scheme and show that the resulting functor G↦ π1(G) is exact.
@article{bwmeta1.element.doi-10_2478_s11533-013-0363-0,
author = {Mikhail Borovoi and Cristian Gonz\'alez-Avil\'es},
title = {The algebraic fundamental group of a reductive group scheme over an arbitrary base scheme},
journal = {Open Mathematics},
volume = {12},
year = {2014},
pages = {545-558},
zbl = {1291.14066},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0363-0}
}
Mikhail Borovoi; Cristian González-Avilés. The algebraic fundamental group of a reductive group scheme over an arbitrary base scheme. Open Mathematics, Tome 12 (2014) pp. 545-558. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0363-0/
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