Characterization of ultra separation axioms via (1,2)alpha-kernel

(Lobachevskii Journal of Mathematics, Volume XXV)

In this paper, we introduce the concept of weakly-ultra-separation of two sets in a bitopological space using (1,2)α-open sets. The (1,2)α-closure and the (1,2)α-kernel are defined in terms of this weakly-ultra-separation. We also investigate the properties of some weak separation axioms like ultra-T₀, ultra-T₁, and ultra-R₀.