ar X iv : m at h / 01 09 10 6 v 1 [ m at h . G N ] 1 7 Se p 20 01 TOPOLOGICAL SEMIGROUPS AND UNIVERSAL SPACES RELATED TO EXTENSION DIMENSION
نویسنده
چکیده
It is proved that there is no structure of left (right) cancelative semigroup on [L]-dimensional universal space for the class of separable compact spaces of extensional dimension ≤ [L]. Besides, we note that the homeomorphism group of [L]-dimensional space whose nonempty open sets are universal for the class of separable compact spaces of extensional dimension ≤ [L] is totally disconnected.
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