Cameron's cofinitary group conjecture (Q1383965)
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scientific article; zbMATH DE number 1139787
| Language | Label | Description | Also known as |
|---|---|---|---|
| English | Cameron's cofinitary group conjecture |
scientific article; zbMATH DE number 1139787 |
Statements
Cameron's cofinitary group conjecture (English)
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1 October 1998
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The author shows that Cameron's conjecture about local compactness of cofinitary subgroups of \(S_\infty\) is false. -- Let \(S_\infty\) be the group of all permutations of \(\mathbb{N}\) endowed with pointwise topology. An element of \(S_\infty\) is called cofinitary if it fixes finitely many elements of \(\mathbb{N}\) only. A subgroup of \(S_\infty\) is said to be cofinitary if all of its elements except the identity are cofinitary. The author proves that every closed subgroup of \(S_\infty\) is a continuous homomorphic image of a closed cofinitary subgroup of \(S_\infty\), thus disproving the attractive hypothesis.
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group of permutations
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cofinitary group
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locally compact homomorphic image
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