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Natural Central Extensions of Groups

Christian Liedtke
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Abstract

Given a group $G$ and an integer $n\geq2$ we construct a new group $\tilde{\cal K}(G,n)$. Although this construction naturally occurs in the context of finding new invariants for complex algebraic surfaces, it is related to the theory of central extensions and the Schur multiplier. A surprising application is that Abelian groups of odd order possess naturally defined covers that can be computed from a given cover by a kind of warped Baer sum.

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Christian Liedtke. 2007-09-13. Natural Central Extensions of Groups. https://arxiv.org/abs/math/0505285

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