Subgroups of products of para $\tau$-discrete semitopological groups

Abstract

In this article we define a new class of topological spaces called para $\tau$-discrete spaces and give an internal characterization of a subgroup of product of para $\tau$-discrete  semitopological groups having character less than or equal to $\tau$. Also we give a partial solution of an open problem posed by Sánchez  [I. Sánchez, Subgroups of products of metrizable semitopological groups, Monatsh Math, 183 (2017), 191–199].