A non-polybounded absolutely closed 36-Shelah group
Abstract
For every infinite cardinal with +=2 we construct a group G of cardinality |G|=+ such that (i) G is 36-Shelah, which means that A36=G for any subset A⊂eq G of cardinality |A|=|G|; (ii) G is absolutely T\!1S-closed and projectively T\!1S-discrete, which means that for every homomorphism h:G Y to a T1 topological semigroup Y the image h[G] is a closed discrete subspace of Y, (iii) G cannot be covered by finitely many algebraic subsets, i.e., subsets of the form \x∈ G:xc1xc2·s xcn=e\ for some c1,c2,·s,cn∈ G.
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