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A note on doubles of groups

Nadia Benakli·Oliver T. Dasbach·Yair Glasner·Brian Mangum
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Abstract

Recently, Rips produced an example of a double of two free groups which has unsolvable generalized word problem. In this paper, we show that Rips's example fits into a large class of doubles of groups, each member of which contains F_2 x F_2 and therefore has unsolvable generalized word problem and is incoherent.

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Nadia Benakli, Oliver T. Dasbach, Yair Glasner, Brian Mangum. 1998-09-23. A note on doubles of groups. https://arxiv.org/abs/math/9809137

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