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Embeddings into P(N)/fin and extension of automorphisms

A. Bella·A. Dow·K. P. Hart·M. Hrusak·J. van Mill·P. Ursino
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Abstract

Given a Boolean algebra B and an embedding e:B -> P(N)/fin we consider the possibility of extending each or some automorphism of B to the whole P(N)/fin. Among other things, we show, assuming CH, that for a wide class of Boolean algebras there are embeddings for which no non-trivial automorphism can be extended.

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A. Bella, A. Dow, K. P. Hart, M. Hrusak, J. van Mill, P. Ursino. 2001-12-13. Embeddings into P(N)/fin and extension of automorphisms. https://arxiv.org/abs/math/0112136

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