We give explicit formulas for reducing the problem of determining whether a given 2-cocycle is a coboundary and if so finding a lifting 1-cochain to a system of norm equations.
@article{bwmeta1.element.doi-10_2478_s11533-013-0319-4,
author = {Thomas Preu},
title = {Effective lifting of 2-cocycles for Galois cohomology},
journal = {Open Mathematics},
volume = {11},
year = {2013},
pages = {2138-2149},
zbl = {1328.12009},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0319-4}
}
Thomas Preu. Effective lifting of 2-cocycles for Galois cohomology. Open Mathematics, Tome 11 (2013) pp. 2138-2149. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0319-4/
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