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arXiv · 1405.3870

A formula for the second cohomology of two-step nilpotent groups

Karel Dekimpe·Manfred Hartl·Sarah Wauters
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Abstract

In [5], the notion of polynomial cocycles is used to give an expression for the second cohomology of T-groups with coefficients in a torsion-free nilpotent module. We make this expression concrete in the case of a T-group G of nilpotency class <=2 and coefficients in a trivial G-module, using a Lie algebra associated to the group. This approach allows us to construct explicit cocycles representing the elements of the second cohomology group.

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Karel Dekimpe, Manfred Hartl, Sarah Wauters. 2014-05-15. A formula for the second cohomology of two-step nilpotent groups. https://arxiv.org/abs/1405.3870

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