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arXiv · 2501.16536

On Isbell's Density Theorem for bitopological pointfree spaces I

M. Andrew Moshier·Imanol Mozo Carollo·Joanne Walters-Wayland
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Abstract

This paper addresses dense sub-objects for point-free bitopology in terms of $d$-frames and provides several examples. We characterize extremal epimorphisms in $d$-frames and show that a smallest dense one always exists, establishing a proper analogue of Isbell's Density Theorem for $d$-frames. Further we explore certain questions about the functoriality of assigning the smallest dense sub-object to each pointfree bitopological space.

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M. Andrew Moshier, Imanol Mozo Carollo, Joanne Walters-Wayland. 2025-01-27. On Isbell's Density Theorem for bitopological pointfree spaces I. https://doi.org/10.1016/j.topol.2019.106962

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