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Javier Murgas

Publications and source records attributed to Javier Murgas.

2 recordsLinked to original sources

Selective separability and $q^+$ on maximal spaces

Given a hereditarily meager ideal $\mathcal{I}$ on a countable set $X$ we use Martin's axiom for countable posets to produce a zero-dimensional maximal topology $τ^\mathcal{I}$ on $X$ such that $τ^\mathcal{I}\cap \mathcal{I}=\{\emptyset\}$ and, moreover, if $\mathcal{I}$ is $p^+$ then $τ^\mathcal{I}$ is selectively separable (SS) and if $\mathcal{I}$ is $q^+$, so is $τ^\mathcal{I}$. In particular, we obtain regular maximal spaces satisfying all boolean combinations of the properties SS and $q^+$.

math.GN

Combinatorial properties on nodec countable spaces with analytic topology

We study some variations of the product topology on families of clopen subsets of $2^{\mathbb{N}}\times\mathbb{N}$ in order to construct countable nodec regular spaces (i.e. in which every nowhere dense set is closed) with analytic topology which in addition are not selectively separable and do not satisfy the combinatorial principle $q^+$.

math.GN