8 citations · 25 across the 17 of their papers we have counts for
4 papers · 1 filter
Large Sets in Boolean and Non-Boolean Groups and Topology
Ol'ga V. Sipacheva
Right and left thick, syndetic, piecewise syndetic, and fat sets in groups are studied. The main concern is the interplay between such sets in Boolean groups. Natural topologies cl…
Unconditionally tau-Closed and tau-Algebraic Sets in Groups
Ol'ga V. Sipacheva
Families of unconditionally -closed and -algebraic sets in a group are defined, which are natural generalizations of unconditionally closed and algebraic sets defined by Mark…
A Class of Groups in Which All Unconditionally Closed Sets are Algebraic
Ol'ga V. Sipacheva
It is proved that, in certain subgroups of direct products of countable groups, the property of being an unconditionally closed set coincides with that of being an algebraic set. I…
Consistent solution of Markov's problem about algebraic sets
Ol'ga V. Sipacheva
It is proved that the continuum hypothesis implies the existence of a group M containing a nonalgebraic unconditionally closed set, i.e., a set which is closed in any Hausdorff gro…