Changing the heights of automorphism towers

Joel David Hamkins, Simon Thomas

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

If G is a centreless group, then τ(G) denotes the height of the automorphism tower of G. We prove that it is consistent that for every cardinal λ and every ordinal α<λ, there exists a centreless group G such that (a) τ(G)=α; and (b) if β is any ordinal such that 1≤β<λ, then there exists a notion of forcing P, which preserves cofinalities and cardinalities, such that τ(G)=β in the corresponding generic extension VP.

Original languageEnglish (US)
Pages (from-to)139-157
Number of pages19
JournalAnnals of Pure and Applied Logic
Volume102
Issue number1-3
DOIs
StatePublished - Mar 3 2000

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Automorphism
Forcing
Cardinality
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All Science Journal Classification (ASJC) codes

  • Logic

Cite this

Hamkins, Joel David ; Thomas, Simon. / Changing the heights of automorphism towers. In: Annals of Pure and Applied Logic. 2000 ; Vol. 102, No. 1-3. pp. 139-157.
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Changing the heights of automorphism towers. / Hamkins, Joel David; Thomas, Simon.

In: Annals of Pure and Applied Logic, Vol. 102, No. 1-3, 03.03.2000, p. 139-157.

Research output: Contribution to journalArticle

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