The homotopic type of certain compact semigroups
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The relation between homotopic types of compact linearly connected semigroups and their minimal ideals is investigated. In Theorem 1 we prove that, if a semigroup has a homotopic unit, even if it is only one-sided, then the minimal ideal is a deformation retract of the semigroup and so is homotopically equivalent to the semigroup. In Theorem 2 it is proved that a Q-semigroup is weakly homotopically equivalent to its minimal ideal.
KeywordsHomotopic Type Minimal Ideal Compact Semigroup Deformation Retract Homotopic Unit
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