ArticleOriginal scientific text
Title
Imposing psendocompact group topologies on Abeliau groups
Authors 1, 2
Affiliations
- Department of Mathematics, Wesleyan University, Middletown, Connecticut 06459, U.S.A.
- Institut Für Mathematik, Universität Hannover, Welfengarten 1, D-3000 Hannover, Germany
Abstract
The least cardinal λ such that some (equivalently: every) compact group with weight α admits a dense, pseudocompact subgroup of cardinality λ is denoted by m(α). Clearly, . We show:
Theorem 4.12. Let G be Abelian with |G| = γ. If either m(α) ≤ α and m , or α > ω and , then G admits a pseudocompact group topology of weight α.
Theorem 4.15. Every connected, pseudocompact Abelian group G with wG = α ≥ ω satisfies .
Theorem 5.2(b). If G is divisible Abelian with , then G admits at most -many pseudocompact group topologies.
Theorem 6.2. Let or with β ≥ α, and let . Then both and the free Abelian group on γ-many generators admit exactly -many pseudocompact group topologies of weight κ. Of these, some -many form a chain and some -many form an anti-chain.
Keywords
pseudocompact group, -dense subgroup, singular cardinals hypothesis, torsion-free rank, connected topological group, 0-dimensional group, divisible hull, chain, anti-chain
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Additional information
http://matwbn.icm.edu.pl/ksiazki/fm/fm142/fm14232.pdf