2019
Том 71
№ 11

# Ideals of the semigroup of ultrafilters of a topological group

Protasov I. V.

Abstract

We construct two new series of closed left ideals of the semigroup $\bar \tau$ of ultrafilters of a topological group (G, τ). The first series gives a disjunctive decomposition of τ-absorbing ultrafilters. Under certain restrictions on the topology of the group (G, τ), the second series gives a disjunctive decomposition of the semigroup of free ultrafilters. For a nondiscrete metrizable topological group (G, τ), we construct a large free subsemigroup of the semigroup $\bar \tau$ .

English version (Springer): Ukrainian Mathematical Journal 47 (1995), no. 4, pp 588-593.

Citation Example: Protasov I. V. Ideals of the semigroup of ultrafilters of a topological group // Ukr. Mat. Zh. - 1995. - 47, № 4. - pp. 506–511.

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